REPORT ON THE SOUTH AMERICA GEOID 2000

The South America Geoid 2000 workshop held at Escola Politécnica, Universidade de São Paulo, from May 17 to19, 2000, was organized by IGeS (International Geoid Service), SCGGSA (Sub-Commission for Gravity and Geoid in South America), CDC (Committee for Developing Countries) and it was also supported by IAPSO (International Association of the Physical Science of the Ocean). The workshop had the following objectives:

· To assemble as many countries as possible from South America to compute a geoid model.

· To encourage cooperation between oceanographers and geodesists for the computation od geoid in coastal areas.

· To encourage every country to cooperate with SCGGSA for data delivery.

· To encourage every country to compute a local geoid model with the data available.

· To discuss different efforts for data acquisition in the continent.

The countries that participated to the activities were the following:

Argentina, Brazil, Chile, Ecuador, Paraguay and Uruguay.

The program of the workshop (attached) addressed special attention to the geoid, but, airborne gravity and the next special satellites: Champs, GRACE and GOCE received attention too in a lecture.

A decisive contribution to the success of the workshop came from the participation of Riccardo Barzaghi (Italy), René Forsberg (Denmark) and Ole Andersen (Denmark).

One day and half was dedicated to geoid computations. Every country had a computer available with softwares to accomplish the different tasks: Stokes numerical integration, fast Fourier techniques and fast collocation.

A few meetings were also organized to discuss the following topics: SIRGAS, CDC, the new structure of IAG and airborne gravity.

D. Blitzkow.

REPORT OF THE 14TH INT. SYMPOSIUM ON EARTH TIDES (ETS2000)

The 14th International Symposium on Earth Tides (ETS2000) was successfully held in Mizusawa, Japan, during the period from August 28 to September 1, 2000. 137 participants from 21 countries reported fully on their results of continuing researches on Earth tides and thus contributed to the progress of further research of Earth and Planetary Tides.

1. Officers of the Commission

The President of the IAG Commission V (Earth Tides) was elected by the Council of IAG at the IUGG/IAG General Assembly held in Birmingham, UK, in July 1999.Before the opening session of the ETS2000, the President consulted opinion of the National Representatives of the Commission on proposal to ask Jacques Hinderer and Olivier Francis to continue their office until the next IUGG/IAG General Assembly to be held in Sapporo, Japan, in July 2003, and obtained their approval.

At the opening session of ETS2000, the Commission elected J. Hinderer as Vice-President and Francis as Secretary without a dissenting voice. Congratulation to Jacques Hinderer and Olivier Francis, and the best wishes for their future work.

3. ETC Homepage

Now, the ETC Homepage can be seen through the following address,

http://www-geod.kugi.kyoto-u.ac.jp/iag-etc/

4. 2nd ETC Medal

The ETC steering committee decided to award the 2nd ETC Medal (ETC Medal 2000) to the late Prof. Hans-Georg Wenzel for his outstanding contribution to international cooperation in earth tide research. His contribution to gravity and Earth tides researches is so well known through the papers more than 150. He is famous by development of a new tidal potential catalogue, a worldwide synthetic gravity tides model, and the Earth tides data processing package so called ETERNA. With grateful appreciation for the numerous services rendered by Prof. Hans-Georg Wenzel during his lifetime, all participants of ETS2000 paid one-minute's tribute to him with deepest sympathy. The ETC awarded the 2nd ETC Medal to Ms Marion Wenzel at the Opening Session of ETS2000 on August 28 2000 at Mizusawa, Japan.

5. ETC Working Groups

At the opening session of ETS2000, chairpersons of following Working Groups reported their activities,

Working Group 4 "Calibration of Gravimeters", (M.van Ruymbeke),

Working Group 5 "Global Gravity Monitoring", (B. Richter),

Working Group 6 "Earth Tides in Geodetic Space Techniques, (H. Schuh),

Working Group 7 "Analysis of Environmental data for the interpretation of gravity measurements", (G. Jentzsch).

The Earth Tide Commission thanks all members and chairpersons of WGs which have been active during the last period, for their fruitful work.

ETC accepted the conclusions of the reports of the Working Groups and decided according to their wishes:

To close Working Group 4 (Calibration of Gravimeters, Chairperson: M.van Ruymbeke).

To close Working Group 5 (Global Gravity Monitoring, Chairperson: B. Richter).

To extend for another 4 year term the activities of the Working Group 6 (Earth Tides in Geodetic Space Techniques) under the new chairperson-ship.

To extend for another 4 year term the activities of the Working Group 7 (Analysis of Environmental data for the interpretation of gravity measurements) under the new chairperson-ship.

To create Working Group 8 on "Gravitational Physics" under the chairperson-ship of Prof. Lalu Manshinha to tackle among others the following scientific problems: The Problem of Aberration: Modern tidal position catalogs assume that the true position of the tide causing body is responsible for the tidal forces, rather than the apparent position, as in optical astronomy. The problem may have consequences, as it may imply relative velocities between the gravity and optical signals. This is a case for experts in Celestial Mechanics and in Earth Tides. The Gravitational Shielding:There is currently no accepted theory of gravity that incorporates or predicts gravitational shielding. The problem is possibly different from the absorption of gravitational radiation by matter. The Earth Tide community should think about, and search for, the consequences of shielding.

6. Directing Board of the International Center for Earth Tides (ICET)

The ICET Directing Board (S.Takemoto (Chair), B.Ducarme, T.F.Baker, D.Crossley, H.T.Hsu and O. Francis (Non-voting member)) met together on August 29, 2000 at the Z-hall in Mizusawa. The main subject for discussion was "Future activity of ICET and re-organization of the IAG services". ICET-DB discussed on the GFFS (Gravity Field and Figure of the Earth Service) proposed by Prof. F. Sanso, which is a new Service including activities of BGI, IGeS and ICET.

Because of a restriction of time, ICET-DB could not draw a conclusion at Mizusawa and decided to continue our discussion by E-mail. ICET-DB will draw a conclusion not later than the end of October 2000.

7. RESOLUTIONS adopted by the Earth Tide Commission

The Earth Tide Commission has adopted the following resolutions at the closing session of the 14th International Symposium on Earth Tides, August 28 - September 1, 2000, Mizusawa, Japan.

1/ Recognizing the importance of the observation of tidal effects and of the determination of tidal parameters by space geodetic techniques,

the ETC recommends

to continue this observational effort;

to compare the results obtained by different space geodetic techniques between each other and with the results of ground based tidal measurements.

2/ Recognizing the importance of the new international services on space geodetic techniques

the ETC recommends

that WG6 establishes or intensifies the cooperation with the analysis coordinators of these international services concerning the tidal modelling.

3/ Considering the new fields of tidal research in lunar and planetary geodesy

the ETC recommends

that the tidal community should take an active part in space missions related to lunar and planetary geodesy ;

requests a proper archiving of the data and metadata acquired during those missions and normal access to the world-wide geodetic community.

4/ Considering the increasing interest of the tidal community to lunar and planetary researches

the ETC recommends

that a session on tides on the planets should be included in the future earth tides symposia.

5/ Recognizing the importance of a global Earth coverage with superconducting gravimeters

for the study of weak geophysical signals,

for the determination of the liquid core resonance parameters,

for the study of the polar motion effects on gravity,

for the intercomparison of the load vectors derived from recent ocean tides models,

for the study of global and regional gravity changes to validate the results of the dedicated satellite missions,

the ETC recommends

to extend the GGP observation period for an additional 6 year period starting July 2003, to maintain the existing sites and to encourage the installation of new GGP stations especially in the Southern hemisphere and in polar regions.

6/ Recognizing the fact that presently the calibration of the superconducting gravimeters participating to the world-wide GGP project is not homogeneous

the ETC recommends

that systematic calibration campaigns with absolute gravimeters should be planned and realized before the end of the current GGP observation period, through an international cooperative effort.

7/ Recognizing the importance to keep in operation several calibration techniques for gravimeters to allow a mutual accuracy control,

the ETC recommends

that inertial calibration platforms and moving mass calibration devices should continue to be developed or maintained besides more usual calibration methods such as intercomparison with absolute or well-calibrated relative instruments.

8/ Recognizing the importance of environmental data for the interpretation of tidal measurements the ETC recommends:

a/ to record the following parameters:

- The barometric pressure, temperature, precipitation, and ground water level. The sampling rate for the recording of environmental parameters should correspond to the sampling rate of the geodynamic data observed. A sufficient resolution and accuracy of the measurements of the environmental parameters should be granted.

- Although the difficulties of monitoring soil moisture are recognized, its is recommended to undertake efforts to realize a continuous monitoring of this parameter.

- The monitoring of wind is also recommended because wind might produce short-period noise as well as long-period modulations.

b/ to correct gravity data in long term studies for local (diameter 100 km), regional (diameter 2000 km), and global atmospheric pressure signals as all three produce significant effects.

c/ to develop correction models for gravity, tilt, and strain related to:

- ground water table variations

- snow, rain and soil moisture

- stress resulting from temperature variations

9/ Noting the importance for tidal measurements of accurate error estimates

and appreciating that such estimates can be made only if the power spectral density of the noise is known

the ETC recommends

to show noise spectra as Power Spectral Density expressed in unit 2/ frequency.

10/ On behalf of all participants of the 14th International Symposium on Earth Tides, the ETC thanks the Japanese National Committee for Geodesy, the Science Council of Japan, the Geodetic Society of Japan, the National Astronomical Observatory of Japan, the City of Mizusawa and the Iwate Prefecture for their generous support to the Symposium.

11/ ETC thanks the Local Organising Committee : Masatsugu Ooe (Chairman), Tadehiro Sato (Secretary) , Jiro Segawa (President of Geodetic Society of Japan) and the staff, for their wonderful welcome and their many efforts in making the 14th International Symposium on Earth Tides a great scientific success.

8. IAG Travel Awards

The following 5 persons are winners of IAG Travel Award.

Alexander Kopaev, (Moscow, Russia), Janusz Bogusz, (Warsaw, Poland), Carla Braitenberg, (Trieste, Italy), Sun He-Ping (Wuhan, P.R. China), Zhigen Yang (Shanghai, P.R. Chin)

9. Publication of the ETS2000

Proceedings of scientific papers will be published as a special issue of the Jour. Geod. Soc. Japan. Other Report on the ETS2000 including the list of participants will be appeared in the next issue of BIM

10. Next Symposium

During the ETS2000, Canadian Colleagues (Profs. D. Smylie, L. Mansinha and S. Pagiatakis) kindly offered to have the next (15th) International Symposium on Earth Tides in Canada in 2004. The Earth Tide Commission acknowledges the receipt of this invitation.

Shuzo Takemoto

IAG/IAPSO JOINT WORKING GROUP ON GEODETIC EFFECTS OF NONTIDAL OCEANIC PROCESSES

Meeting held on March 29, 2001 in Nice, France in conjunction with the XXVI General Assembly of the European Geophysical Society (EGS) during which presentations were given by R. Gross, T. Sato, B. Chao, and A. Brzezinski.

Recognizing the important role that nontidal oceanic processes play in Earth rotation dynamics, an IAG/IAPSO Joint Working Group on Geodetic Effects of Nontidal Oceanic Processes was formed at the XXII General Assembly of the IUGG in Birmingham. The objective of this IAG/IAPSO Joint Working Group is to investigate the effects of nontidal oceanic processes on the Earths rotation, deformation, gravitational field, and geocenter, and to foster interactions between the geodetic and oceanographic communities in order to promote greater understanding of these effects. R. Gross described the International Earth Rotation Service (IERS) Special Bureau for the Oceans (SBO). The IERS Special Bureau for the Oceans is one of seven Special Bureaus of the IERS Global Geophysical Fluids Center

(GGFC) which was established on January 1, 1998 in order to help relate dynamical properties of the atmosphere, oceans, mantle, and core to motions of the Earth, including its rotation. In particular, the IERS Special Bureau for the Oceans is responsible for collecting, calculating, analyzing, archiving, and distributing data relating to nontidal changes in oceanic processes affecting the Earth's rotation, deformation, gravitational field, and geocenter. The oceanic products available through the IERS SBO are produced primarily by general circulation models of the oceans that are operated by participating modeling groups and include oceanic angular momentum, center-of-mass, bottom pressure, and torques. Through the IERS SBO web site at http://euler.jpl.nasa.gov/sbo, oceanic data can be downloaded and a bibliography of publications pertaining to the effect of the oceans on the solid Earth can be obtained. Currently, two different oceanic angular momentum data sets are available. The IERS SBO is one possible source of data that can be used by the IAG/IAPSO Joint Working Group in their investigations on the geodetic effects of nontidal oceanic processes.

T. Sato discussed the effect of sea surface height variations on superconducting gravimeter measurements. Good agreement with gravity measurements at 3 different sites were obtained using results from both an ocean model and from TOPEX/POSEIDON measurements which had been corrected for the steric changes in sea surface height that have no gravitational signature. This study of the results of gravity observations clearly shows that gravity measurements from satellites and on the ground have an important role to play when studying the effects of oceanic variability on the local and global geophysical processes of the Earth. He then presented plans for deploying ocean- bottom pressure recorders off the coast of Japan at TOPEX and Jason-1 crossover points.

As the mission scientist for the GRACE Mission Office, B. Chao discussed the use of oceanic general circulation models to dealias GRACE gravitational field measurements. The GRACE project is currently planning on producing gravitational field solutions at monthly intervals. Since the distribution of mass within the oceans changes more rapidly than this, the gravitational effect of this rapid oceanic mass movement will be aliased in the monthly solutions unless it is modeled and removed from the GRACE measurements. A barotropic, or perhaps a baroclinic, ocean model driven by either NCEP or ECMWF surface winds and fluxes will likely be operated by the GRACE project in order to model and remove the high frequency variations in oceanic mass distribution that will not be sampled by the GRACE monthly gravitational field solutions. Since this scheme will most likely not be able to perfectly remove the aliased signals, the user community should be cognizant of the uncertainties that will be introduced by this procedure. Similar aliasing effects are also expected to occur due to rapid atmospheric, hydrologic, and ocean-tidal mass movement, and the GRACE project is also planning to use atmospheric and ocean tide models to similarly remove these effects.

A. Brzezinski summarized the results on the oceanic excitation of the Chandler wobble that he and J. Nastula presented at the 33rd COSPAR Scientific Assembly held in Warsaw, Poland during July 16-23, 2000 (to appear in Advances in Space Research). Using the POLE98 polar motion series, the NCEP/NCAR reanalysis atmospheric angular momentum series obtained from the IERS Special Bureau for the Atmosphere, and the 11-year-long oceanic angular momentum (OAM) series of Ponte et al. (J.Geophys. Res., vol. 104, pp. 23393-23409, 1999) obtained from the IERS SBO, they demonstrated that the OAM series is highly coherent with the lacking non-atmospheric excitation of the observed Chandler wobble signal. In terms of the excitation power, the combined effect of the atmosphere and ocean explains about 80% of the free wobble, which agrees to within 1-sigma uncertainty with the result recently published by R. Gross (Geophys. Res.Lett., vol. 27, pp. 2329-2332, 2000).

The next meeting is scheduled to be held in conjunction with the XXVII General Assembly of the EGS that will be held in Nice, France during April 22-26, 2002. The exact date and time of this meeting will be announced later. In order to receive announcements of this and all future meetings, please contact Richard Gross at richard.Gross@jpl.nasa.gov.

R. Gross

FIRST INTERNATIONAL SYMPOSIUM ON ROBUST STATISTICS AND FUZZY TECHNIQUES IN GEODESY AND GIS, ZURICH, SWITZERLAND, MARCH 12-16, 2001

The 'First International Symposium on Robust Statistics and Fuzzy Techniques in Geodesy and GIS' took place at the Swiss Federal Institute of Technology (ETH) in Zurich, Switzerland, from March 12-16, 2001. It was initiated by the members of the Special Study Group (SSG) 4.190 of the International Association of Geodesy (IAG) on 'Non-probabilistic assessment in geodetic data analysis'. It was organized by Prof. A. Carosio, ETH Zurich,, and Dr. H. Kutterer, DGFI Munich, chairman of the SSG. Nearly 60 participants from 15 countries attended the symposium.

and photogrammetry. Therefore five technical sessions and a panel discussion were organized. In advance, two tutorials were given on robust statistics (A. Carosio) and on fuzzy logic (H. Kutterer, S. Schön) on monday, March 12.

The symposium was opened on tuesday, March 13, with a welcome address by Prof. B. Heck, University of Karlsruhe, president of the IAG section IV. Two invited lectures followed. The first one was presented by Prof. F. Hampel, ETH Zurich, who considered both the historical development of robust statistics and recent mathematical problems. The second one was given by Prof. R. Viertl, Technical University of Vienna, who motivated the non-precision approach and showed the application of statistical methods to non-precise data based on the extension principle of fuzzy theory. H. Kutterer gave the last lecture in this session on a general viewpoint of uncertainty assessment.

In the technical session on geodetic engineering four talks were focussed on robust statistics: kinematic positioning (Y. Yang), the BIBER estimator (F. Wicki), and the reliability of robust estimators (M. Berber, S. Hekimoglu). One talk considered the use of interval mathematics for the measurement uncertainties (S. Schön). L. Soukup discussed 'least squares without minimization'.

The second technical session on deformation analysis showed a variety of different assessment methods: a conic fitting algorithm (O. Akyilmaz), inference on deformation measures like strain tensors (J. Cai), fuzzy deformation analysis (K. Heine), Plucker coordinates (R. Jurisch), artificial neural networks (J. B. Miima), modelling alternatives in deformation measurements (D. Rossikopoulos), and maximum correlation adjustment (F.

Neitzel).

The third session which was on Geographic Information Systems (GIS) consisted of four talks, three using fuzzy logic (G. Joos, S. Keller, E. Stefanakis) and one on robust estimation techniques (E. Kanani). The following session was dedicated to GPS data processing and analysis: real-time prediction of failures (C. Dacheng), robust techniques (A. Wieser, Y. Yang), and fuzzy methods (S. Leinen, H. Kutterer).

The last technical session of the symposium was on photogrammetry, remote sensing, and image processing. F. Sanso discussed the Wiener-Kolmogorov prediction problem with the application to digital terrain models. L. Mussio considered semantic ambiguity questions for pattern recognition. M. Scaioni showed the use of the LMS estimator for outlier rejection in automatic aerial triangulation.

non-probabilistic techniques. A panel discussion on data analysis within IAG closed the symposium.

The proceedings of the symposium are published as Report No. 295 of the Institute of Geodesy and Photogrammetry of the Swiss Federal Institute of Technology Zurich (ETH). Further information can be found on the website of the IAG SSG 4.190. The address is www.dgfi.badw.de/ssg4.190. Last but not least a warm thanks goes to the local committee around A. Carosio at the ETH Zurich for the excellent organization of the symposium.

H. Kutterer

IAG Subcommission for Europe (EUREF)

The 11th symposium of the EUREF Subcommission

was held in Dubrovnik from 16. - 19.5.2001. Proceedings will be published in AMitteilungen des Bundesamtes für Kartographie und Geodäsie@.

On this symposium the following resolutions were adopted:

Resolution No. 1

The IAG Subcommission for Europe (EUREF)

recognising that

-in May/June 1994 the EUREF-SLOCRO-94 campaign in Slovenia and Croatia was observed,

-in September/October 1995 the Slovenia-95 and CROREF-95 campaigns in Slovenia and Croatia were observed,

-in August/September 1996 the CROREF-96 campaign in Croatia was observed,

and all the results were submitted to the EUREF Technical Working Group as a combined EUREF-CRO-94/95/96 solution, where it was accepted as class B standard (about 1 cm at the epoch of observations)

endorses the subsets of points for Croatia submitted to the EUREF Technical Working Group as improvements and extensions of EUREF89,

but considering that two points in Croatia observed during the EUREF-CROSLO-94 campaign were destroyed,

recommends that all old Croatian points should be deleted from the EUREF database and replaced by the subset of points selected from the EUREF-CRO-94/95/96 solution.

Resolution No. 2

The IAG Subcommission for Europe (EUREF)

considering

- the availability of the ITRF2000 as an improved and accurate realisation of the ITRS,

-the improved determination of the rotation of the Eurasian plate using ITRF2000 site velocities,

recommends to replace the NNR-NUVEL-1A rotation rate values by the ones derived from ITRF2000 in the transformation formula linking ETRS89 to ITRS.

Resolution No. 3

The IAG Subcommission for Europe (EUREF)

recognising the significant practical and scientific value of the EVRS

noting the usefulness of improving its realisation EVRF2000

asks national levelling data providers to UELN/EUVN to inform the Technical Working Group on the tidal system and other corrections used,

recommends that in the future levelling data be submitted in the zero tidal system according to the EVRS definition and corresponding IAG resolution 16, 1983.

Resolution No. 4

The IAG Subcommission for Europe (EUREF)

recognising

-the European Vertical GPS Reference Network (EUVN) with its GPS-derived ellipsoidal heights and levelled connections to UELN,

-the definition of the European Vertical Reference System EVRS with its first realisation UELN 95/98, called EVRF2000,

considering

-this implicit pointwise realisation of a European geoid consistent with both ETRS89 and EVRS,

-the existence of a large number of regional and local geoids in Europe,

-the urgent need by the navigation community for a height reference surface,

asks its Technical Working Group and the European Subcommission of the IAG IGGC (International Gravity and Geoid Commission) to take all necessary steps to generate a European geoid model of decimetre accuracy consistent with ETRS89 and EVRS.

Resolution No. 5

The IAG Subcommission for Europe (EUREF), which held its eleventh EUREF symposium in Dubrovnik from May 16-18, 2001, expresses its heartfelt thanks to the Local Organising Committee, its chairman Zeljko Bacic and the State Geodetic Administration, as well as the Cadastre Office in Dubrovnik and the International Centre of Croatian Universities, for organising the symposium and for the excellent arrangements resulting in a very successful meeting.

Joao Agria Torres, Lisbon: jatorres@ipcc.pt

Helmut Hornik, Munich: hornik@dgfi.badw.de

MEETING REPORTS

FIRST INTERNATIONAL SYMPOSIUM ON ROBUST STATISTICS AND FUZZY TECHNIQUES IN GEODESY AND GIS

ZURICH, SWITZERLAND, MARCH 12-16, 2001

The 'First International Symposium on Robust Statistics and Fuzzy Techniques in Geodesy and GIS' took place at the Swiss Federal Institute of Technology (ETH) in Zurich, Switzerland, from March 12-16, 2001. It was initiated by the members of the Special Study Group (SSG) 4.190 of the International Association of Geodesy (IAG) on 'Non-probabilistic assessment in geodetic data analysis'. It was organized by Prof. A. Carosio, ETH Zurich, and Dr. H. Kutterer, DGFI Munich, chairman of the SSG. Nearly 60 participants from 15 countries attended the symposium.

The program of the meeting consisted of applications of robust statistics and fuzzy theory, mainly in the fields of geodetic engineering, deformation analysis, geographic information systems, satellite-based positioning (GPS), and photogrammetry. Therefore five technical sessions and a panel discussion were organized. In advance, two tutorials were given on robust statistics (A. Carosio) and on fuzzy logic (H. Kutterer, S. Schön) on monday, March 12.

The last day of the symposium started with an introductory talk by F. Sanso on the challenges for the IAG in data analysis in the fields of geodesy and GIS, especially regarding the modelling of uncertainty by probabilistic and non-probabilistic techniques. A panel discussion on data analysis within IAG closed the symposium.

H. Kutterer

SECOND INTERNATIONAL SYMPOSIUM: GEODYNAMICS OF THE ALPS-ADRIA AREA BY MEANS OF TERRESTRIAL AND SATELLITE METHODS

Last autumn the beautiful city of Dubrovnik became a meeting point of the international geodetic community again. It was after a long interruption lasting almost exactly 9 years. In 1989 the participants of the First International Symposium on Gravity Field Determination and GPS-Positioning in the Alps-Adria Area left the Dubrovnik Inter-University Centre, the venue of the symposium, with a believe that they will reconvene at the same place in four years. However, the reality and the difficult time in this area prepared another development.

Only last year the reconstructed Inter-University Centre of Dubrovnik became the venue of the Second International Symposium: Geodynamics of the Alps-Adria Area by means of Terrestrial and Satellite Methods which was held here between September 28 and October 2, 1998. The symposium was sponsored by the International Association of Geodesy and it also had a generous local support. In total 43 interesting papers were presented by scientists coming from 9 different countries to the audience of over 70 participants. The meeting was organized by Prof. K. Èoliæ (as the local organizer, University of Zagreb) and Prof. H. Moritz (as the international co-organizer).

At the opening session a number of addresses was presented by local and international representatives. Then the participants of the symposium heard a very interesting lecture by K. Èoliæ and H. Moritz on Rudjer Boškoviæ (1711-1787), a native of Dubrovnik and a remarkable figure in the history of modern European science who also made considerable contributions to geodesy and geophysics.

The symposium itself was subdivided into 10 session: 3 sessions were devoted to Geodynamics and chaired subsequently by H. Seeger, G. Rossi and C. Marchesini. Then G. Schmitt chaired a session on Geoid, F. Vodopivec a session on GPS, P. Holota a session on Positioning and Gravity, P. Pesec chaired a session on CERGOP, E. Groten a session on the Theory and finally two session devoted to practical works were chaired by A. Zeman and K. Kaniuth.

The first session on Geodynamics started with a paper by Hussein A. Abd-Elmotaal who discussed inverse Vening Meinesz Moho depths for the Eastern Alps. Then Z. Altiner et al. presented a talk on crustal deformations in the Adriatic sea area as inferred on the basis of GPS observations. Subsequently, E. Groten and St. Leinen treated deformation monitoring around a large viaduct close to Istambul using GPS and levelling. Finally, F. Vodopivec and D. Kogoj discussed the geodynamics in Slovenia and A. Zeman approached a problem of estimating vertical dynamics on the territory of former Austro-Hungarian empire on the bases of results of historical levellings.

The second session on Geodynamics was opened by A. Caporali who in his talk attacked a problem of constraining the rheology of continental lithosphere near Orogens with the use of Bouguer gravity anomalies. The programme of the session continued with a paper by D. Miškoviæ on problems of national reference frame and geodynamic investigations in Slovenia. Then B. Richter et al. discussed absolute gravity measurements in Croatia approached as a standardized base net for geodynamic, height and gravity studies. Finally, G. Schmitt and C. Marchesini informed about geodetic activities with respect to geokinematics in Friuli and the Eastern Alps.

At the last session on Geodynamics E. Prelogiæ et al. treated recent tectonic movements and earthquakes in Croatia and then G. Rossi and M. Zadro discussed geodynamic processes at the northern boundary of Adria plate, especially strain-tilt measurements and modelling. The session was closed with a paper by P. Vyskoèil (presented in absentia by H. Moritz) on the map of vertical movements of Dinaridies Eastern Alps, Pannonian Basin and the Bohemian Massif.

As already mentioned, together with geodynamics oriented sessions there were also sessions on closely related topics in Dubrovnik.

The paper by H. Abd-Elmotaal et al. stared the Geoid session. The talk was devoted to the influence of implementing the seismic Moho depths in geoid computation. K. Arsov and H. Sünkel approached the problem of influence of the resolution of DEM in gravity reduction. They used fractal models of the topography for their analyses. E. Groten and K. Seitz discussed a detailed geoid of Germany based on EGM96. N. Kühtreiber presented a recent geoid computation for Audtria and N. Kühtreiber et al. then concluded the session with results of a geoid computation for the central part of the Alps-Adria area.

At the GPS session A. Caporali devoted his talk to an analysis of a GPS network along the Alpine Arc. K. Kaniuth and Stuber attacked the problem of accuracy and reliability of height estimates in regional GPS networks. H. Seeger et al. contributed with results of a re-computation of the EUREF GPS campaigns in Croatia and Slovenia. Finally, M. Marjanoviæ and Lj. Rašiæ discussed the results of the EUREF 1997 GPS campaign in Croatia.

Also the Gravity was discussed at a separate session. Here J. Flury brought an information on a local gravity filed determination in the Estergebirge. E. Gueguen and C. Doglioni discussed the geodynamic evolution of the Appeninic subduction. R. Marjanoviæ-Kavanagh contributed with experiences with a new digital tiltmeter and G. and G.K. Walach presented a Bouguer gravity map of Styria.

The session on CERGOP was opened by D. Miškoviæ et al. They presented results of the GPS-measurements in the Bovec-Tolmin earthquake region. H. Düller and P. Pesec contributed with information on the Austrian permanent GPS-network. P. Pesec then summarized the current status of the Austrian IDNDR project (Crustal dynamics of the Adriatic microplate and the adjacent East-Alpine area). Finally, J. Šimek discussed possible topics for the international cooperation within CEI/CERGOP on the background of current European project.

Within theory oriented session the audience heard a contribution by P. Holota on Galerkin's method in the determination of the disturbing potential. Then an analysis of a straight line equation by M. Lapaine and new concepts of boundary value problems of physical geodesy after GPS presented by H. Moritz.

Finally, two working sessions were devoted to practical works. Here K. Èoliæ et al. contributed with two talks: on the survey of the Plitvice-lakes (the phenomenon in the Karst of the Dinaric Alps with satellite and terrestrial measurements) and on the 3-D geodynamic network of broader area of the city of Zagreb. Then Z. Kapoviæ et al. presented results of the geodynamic research of the historical center in the city of Dubrovnik with precise geometric levelling. Subsequently M. Plazibat approached linear transformation between old and new national networks by means of finite elements and M. Solariæ discussed a visibility analysis of GPS satellites in Central Europe.

At the closing session (chaired by B. Gajèeta) the participants adopted a number of important resolutions. They are as follows:

Resolution 1 - The Symposium,

recognizing the need of a regular exchange of ideas and research results in the field of the ‘tectonic scenario’ in the wider Alps-Adriatic region and

having in mind the hospitality of the Croatian colleagues,

recommends regular meetings in a four years cycle in the city of Dubrovnik, with one intermediate meeting at a different place between two of these symposia.

Resolution 2 - The Symposium,

recognizing the need of further research concerning the ‘tectonic scenario’ in the wider Alps-Adriatic region and of studies concerning earthquake disaster prevention in this region,

recommends the establishment of a corresponding Special Study Group in Section V ‘Geodynamics’ of IAG, with due relation to CERGOP.

Resolution 3 - The Symposium,

considering that the area of the Plitvice Lakes is not only a National Heritage under the patronage of UNESCO (No. 148), but also very important for different reasons such as Dinaric Karst geology, effect of tourism etc. and

considering that important geodetic and geodynamical studies have already been performed by the Geodetic Faculty of Zagreb University,

recommends that this area be declared an International Geodynamic Test Area in which all relevant geodetic methods are to be applied.

Resolution 4 - The Symposium,

recognizing the need of permanent GPS stations and

considering the existence of such stations e.g. in Croatia and Slovenia.

recommends the establishment of at least one permanent GPS station on the territory of Bosnia and Herzegovina.

Resolution 5 - The Symposium,

recognizing the great and successful efforts of Prof. Èoliæ and Prof. Moritz and their staff in preparing and organizing this symposium and

appreciating the importance of the topics under consideration for applied and theoretical surveying, geodesy, geodynamics and related practical activities by universities and state organizations in and around the Alpine-Adriatic Area up to the Panonnian Basin,

expresses its sincere thanks for the wonderful days in the beautiful city of Dubrovnik, which is under the patronage of UNESCO (No. 149), and in the stimulating environment of IUC in free Croatia.

The scientific programme of the symposium was enriched by the presentation of the book by H. Horitz: Science, Mind and the Universe (U. Wichmann Vlg., Heidelberg, 1995) and its translation into Croatian. On this occasion an introductory lecture was held by Acad. N. Trinajstiæ who gave an interesting outline of philosophy and discussed its contemporary trends.

The participants of the symposium spent nice and well organized time together and during an interesting excursion had a possibility to learn more about the marvelous city of Dubrobnik and its beautiful surrounding. The symposium was a clear success. The Proceedings will be published by the Geodetic Survey of Croatia.

P. Holota

REPORT ON THE INTERNATIONAL CONFERENCE ON TECHNICAL ASPECTS OF MARITIME BOUNDARY DELINEATION AND DELIMITATION, INCLUDING UNCLOS ARTICLE 76 ISSUES (ABLOS), MONACE, 9-10 SEPTEMBER, 1999.

Seventy-six attendees from twenty-nine countries were present at the Conference. In addition the International Hydrographic Bureau (IHB) personnel, members of the UN Commission on the Outer Limits of the Continental Shelf and the UN Division of Ocean Affairs and Law of the Sea participated. The sessions and papers were organised by the Conference Committee chaired by P. Vaniçek, chairman of ABLOS, and the Conference Proceedings, containing the 26 paper presented, will be produced by the IHB.

The Conference was divided into four sessions over a span of two days. In the first session, “Issues concerning the UN Commission on the Limits of the Continental Shelf”, convened by G. Carrera, topics related to the approach of the UN CLCS to submissions made by coastal states were considered in contributions presented by members of the Commission. The following papers were delivered: CROKER, Peter, CLCS Member (Ireland), “The mandate and work of the Commission on the Limits of the Continental Shelf”.HINZ, Karl, CLCS Member (Germany), “A review of continental margins of the world”. LAMONT Iain, CLCS Member (New Zealand), “Formulating the New Zealand Continental Shelf Claim: A First Step”. BREKKE, Harald, CLCS Member (Norway), "Uncertainties and errors in sediment thickness”. CARRERA, Galo, CLCS Member (Mexico) “Wide continental margins of the world: a survey of marine scientific requirements and international regional cooperation needs posed by the implementation of Article 76 of UNCLOS”. ALBUQUERQUE, Alexandre and CARRERA, Galo, CLCS Members (Brazil and Mexico) “Information on the outer limits of the extended continental shelf”.

The second session, “Geodetic issues, with emphasis on errors in maritime boundaries and how to reduce them”, convened by B.G. Harsson, dealt with specifically geodetic problems of delineation and delimitation of maritime boundaries. The following papers were delivered: CARRERA, Galo, (Canada) "The impact of the seabed roughness on the location of the outer limits of the extended continental shelf". GROTEN, Erwin, (Germany) "Coastal Boundaries and Vertical Datums. VANIÇEK, Petr, (Canada) "Propagation of errors from shore baselines seaward”.SJOBERG, Lars, M Fan and Milan Horemuz, (Sweden) "Accuracy of computed points on a median line, factors to be considered", MURPHY, Brian, Philip Collier, David Mitchel andl Bill Hirst., (Australia) "Maritime zone boundary generation from straight baselines defined as geodesics”. OSZCZAK, Stanislaw, A.Wasilewski, Z.Rzepecka (Poland) " RTK/ DGPS service in maritime boundary delimitations". ELEMA, I. and Kees de JONG, (The Netherlands) "The determination of boundaries at sea between Belgium and The Netherlands".

The third session, “Tools needed for boundary delimitations”, convened by R. Macnab, dealt specifically with hardware and software that would be necessary to obtain the data to substantiate a continental shelf claim. The following papers were delivered: PALMER, Hal, Lorin Pruett, and Kurt Christensen, (USA), "GIS applications to maritime limit and boundary delimitation”. MONAHAN, David, Michael S. Loughridge, Meirion T Jones, Larry Mayer, (Canada, USA, UK) “A model for using publicly available data and methodologies to begin preparing a claim to an extended continental shelf under article 76 of the United Nations Convention on Law of the Sea (UNCLOS)”. MONAHAN, David and Larry Mayer, (Canada) “An examination of publicly available bathymetry data sets using digital mapping tools to determine their applicability to Article 76 of UNCLOS”. HIRST, Bill, Brian Murphy and Phil Collier, (Australia) "An Overview of Australian Maritime Zone Boundary Definition”. BORISSOVA, Irina Philip A. Symonds, Robin Gallagher, Bruce C. Cotton and Gail Hill, (Australia) "A set of integrated tools based on ArcView for defining the outer limit of Australia's continental shelf". BENNETT, John, (USA) “Contrast of the ‘Surface of Directed Gradients’ with the ‘Surface of Maximum Curvature’ to compute the foot of the continental slope”. HARDING, Jennifer, Herman Varma, John Hart and Ron Macnab, (Canada) “The HH code: facilitating the management, manipulation, and visualization of bathymetric data”.

In the last session, “Other issues and case studies (not necessarily related to Article 76)”, convened by C. Rizos, specific issues and case studies were the subjects of discussion. The following papers were delivered: MONAHAN, David and David Wells, (Canada) “Achievable uncertainties in the depiction of the 2500m contour and their possible impact on continental shelf delimitation”. MACNAB, Ron, (Canada)

"Article 76 in the Arctic - a catalyst for international collaboration". CHERKASHOV, Georgi, A., Gramberg I.S. Makorta A.P., Kaminsky V.D., Naryshkin G.D., Poselov V.A., Sorokin M.Yu. (Russia) “Bathymetry and Deep Structure of the Arctic Continental Margin of Russia in the context of article 76 UN Convention on the Law of the Sea”. COAKLEY, Bernard, (USA) “Contribution of the SCICEX Project Towards the Implementation of Article 76 of the UN Convention on the Law of the Sea in the Arctic Ocean”. SYMONDS, Phil, (Australia) “Austalia’s approach to defining its extended continental shelf: progress and issues arising”.

The Conference, staged in the beautiful new offices of IHB, was considered a great success and a possibility that a bi-annual ABLOS-sponsored conference could become a regular international venture in Monaco was discussed. It was the first time that the IHB offices have been utilised for a conference of this format and it was evident that the facilities would not be adequate to support a conference wit a larger number of participants. It is anticipated that the assistance of the Principality of Monaco will have to be sought if this was to become a regular venture.

P. Vaniçek

MEETING REPORT OF THE IAG/IAPSO JOINT WORKING GROUP ON GEODETIC EFFECTS OF NONTIDAL OCEANIC PROCESSES HELD IN CONJUGATION WITH THE EGS XXV GENERAL ASSEMBLY, NICE, FRANCE, APRIL, 2000.

The oceans have a major impact on global geophysical processes of the Earth. Nontidal changes in oceanic currents and ocean-bottom pressure have been shown to be a major source of polar motion excitation and also measurably change the length of the day. The changing mass distribution of the oceans causes the Earth's gravitational field to change and causes the center-of-mass of the oceans to change which in turn causes the center-of-mass of the solid Earth to change. The changing mass distribution of the oceans also changes the load on the oceanic crust, thereby affecting both the vertical and horizontal position of observing stations located near the oceans. Products of oceanic general circulation models (OGCMs) have been used to study these and other geodetic effects of nontidal oceanic processes. Data assimilation systems similar to those employed in numerical weather prediction are beginning to be used with OGCMs to improve their fidelity. In the near future, time-varying gravitational field measurements, which over the oceans can be interpreted as time-varying ocean-bottom pressure measurements, will be available from the CHAMP and GRACE satellites. The assimilation of these new data types into OGCMs can be expected to further improve the accuracy of global ocean models, and hence the accuracy of the predicted effects of oceanic processes on the Earth's rotation, deformation, gravitational field, and geocenter.

Recognizing the important role that nontidal oceanic processes play in Earth rotation dynamics, an IAG/IAPSO Joint Working Group on Geodetic Effects of Nontidal Oceanic Processes was formed at the XXII General Assembly of the IUGG in Birmingham. The objective of this IAG/IAPSO Joint Working Group is to investigate the effects of nontidal oceanic processes on the Earth_s rotation, deformation, gravitational field, and geocenter, and to foster interactions between the geodetic and oceanographic communities in order to promote greater understanding of these effects. A meeting of this IAG/IAPSO Joint Working Group was held on April 27, 2000 in Nice, France in conjunction with the 25th General Assembly of the European Geophysical Society during which presentations were given by Rui Ponte, Chris Hughes, and Richard Gross.

Rui Ponte discussed an oceanographic data assimilation system being created by collaborators from the Massachusetts Institute of Technology (MIT), the Scripps Institution of Oceanography, and the Jet Propulsion Laboratory. The ocean model component of the data assimilation system, originally developed at MIT, is currently run on a 2x2 degree horizontal grid with constant mixing coefficients and a simple convective adjustment scheme. Future improvements will include finer resolution, more realistic mixed layer physics and eddy parameterizations, and relaxation of the volume conserving formulation. The oceanographic data currently being assimilated include altimetric measurements of sea surface height, hydrographic sections, and sea surface temperature measurements. Other types of data (e.g., floats, XBT profiles) will also be included in the future. Routine calculation of oceanic angular momentum and torque quantities from the output of the assimilation system is envisioned.

Chris Hughes described the GLObal Undersea Pressure (GLOUP) data bank. For more information about GLOUP and/or to obtain the series of historical ocean-bottom pressure measurements see the GLOUP home page at http://www.pol.ac.uk/psmslh/gloup/gloup.html.

Richard Gross described the International Earth Rotation Service (IERS) Special Bureau for the Oceans (SBO). The IERS Special Bureau for the Oceans is one of seven Special Bureaus of the IERS Global Geophysical Fluids Center (GGFC) which was established on January 1, 1998 in order to help relate dynamical properties of the atmosphere, oceans, mantle, and core to motions of the Earth, including its rotation. In particular, the IERS Special Bureau for the Oceans is responsible for collecting, calculating, analyzing, archiving, and distributing data relating to nontidal changes in oceanic processes affecting the Earth's rotation, deformation, gravitational field, and geocenter. The oceanic products available through the IERS SBO are produced primarily by general circulation models of the oceans that are operated by participating modeling groups and include oceanic angular momentum, center-of-mass, bottom pressure, and torques. Through the IERS SBO web site at http://euler.jpl.nasa.gov/sbo, oceanic data can be downloaded and a bibliography of publications pertaining to the effect of the oceans on the solid Earth can be obtained. Currently, two different oceanic angular momentum data sets are available. The IERS SBO is therefore one possible source of data that can be used by the IAG/IAPSO Joint Working Group in their investigations on the geodetic effects of nontidal oceanic processes.

Meetings of the IAG/IAPSO Joint Working Group on Geodetic Effects of Nontidal Oceanic Processes are planned to be held twice-per-year in conjunction with major conferences in order to foster interactions on this topic between the geodetic and oceanographic communities. These meetings, which are open to all interested individuals, will generally be held in the Spring in conjunction with the EGS conference in Europe and in the Fall in conjunction with the Fall AGU conference in the United States. The next meeting will be held in conjunction with the Fall 2000 AGU conference in San Francisco, California during December 15-19, 2000 with the exact date and time to be announced later. In order to receive announcements about this and all future meetings, please contact Richard Gross by sending an email message to him at Richard.Gross@jpl.nasa.gov. R. Gross

WORKING MEETING OF THE IAG SSG 4.190 ON NON-PROBABILISTIC ASSESSMENT IN GEODETIC DATA ANALYSIS

The first working meeting of the IAG SSG 4.190 took place at the Geodetic Institute, University of Karlsruhe (GIK), on April 7, 2000. 11 members and corresponding members were participating. The meeting was opened with a welcome note by B. Heck, president of the IAG Section IV on General Theory and Methodology. H. Kutterer, chairman of the SSG, continued with a short review of the terms of reference and objectives. The main part of the meeting consisted of oral presentations by members of the SSG on the topics fuzzy-theory (E. A. Shyllon, K. Heine), robust estimation (A. Carosio), artificial neural networks (J. B. Miima), interval mathematics (S. Schön), GIS for local geoid computation (M. Brovelli), and on general uncertainty theory (H. Kutterer).

It was decided to have annual closed working meetings of the SSG. Besides, it is planned to organize an open international workshop on robust and fuzzy techniques in March 2001 in Zürich.

The financial support of the stay of E. A. Shyllon by the IAG is gratefully acknowledged as well as the sponsoring of the organization of the meeting by the GIK.

H. Kutterer

Meeting Reports

Minutes of the Organizational Meeting for African Reference System "AFREF"

Held April 27, 2000, Centre Universitaire Mediterranean (CUM), Nice, France

Meeting Objective:

Discuss possible organization of a project to establish a common geodetic reference system throughout Africa compatible with the International Terrestrial Reference System (ITRF). Discuss ways to involve the international geodesy community to work with African nations to develop a single, uniform, continental geodetic reference

system meeting international standards to replace the myriad national reference systems, many of which have not been maintained, and are out of date and inaccurate.

Meeting Organization:

Called by Claude Boucher, head of Commission X of the International Association of Geodesy (IAG) "Global and Regional Networks", also head of the ITRF and the representative of the International Earth Rotation Service (IERS) to the International GPS Service (IGS). The IGS is active globally in supporting the mission of the IAG & IERS/ITRF through the techniques and applications of the Global Positioning System (GPS). GPS is the most economical and widely accessible modern geodetic technology for realizing a continental reference network throughout Africa.

Executive Summary

The decision was taken at this preliminary meeting to pursue the coordination of a project designated "AFREF", the objective of which is to establish a continental, robust and homogenous geodetic reference system throughout Africa. Africa remains the only continent with paucity of satellite geodetic measurements, especially GPS observations, either episodic, or continuous. There are a few notable exceptions: locations in South Africa, single stations in Malindi, Kenya; Mas Palomas, Canary Islands, Spain; Libreville, Gabon and at previous times a station each in Ghana and Cote 'd Ivorie.

Difficulties of in-country support, communications, reliable infrastructure and lack of resources hinder permanent, high quality GPS station implementations a Helwan, Egypt; Adis Ababa, Ethiopia; Rabat, Morocco; and Kampala, Uganda, for example, where equipment have been installed.

This meeting and earlier ad-hoc discussions have highlighted the importance of a renewed effort to realize a reference system for this continent through international collaboration directly with the African nations. It was emphasized that the must truly be a joint effort with Africans to be successful and that it must focus on the

transfer of appropriate technology to sustain the references with modern instrumentation, e.g. GPS and other satellite techniques. It is also noted that resources will be required to enable organizational participation and project activities (e.g. travel, equipment, technical support, etc.)

The meeting attendees agreed to further explore and pursue a joint project 'AFREF' with the Africans and other international partners, and that such a project should:

Support and ensure the fundamental basis for the national 3-d reference networks for today and in the future through a continental African geodetic network fully consistent and homogeneous with the global reference frame of the ITRF.
Establish continuous, permanent GPS stations such that each nation or each user has free access (and at least within 1000km) of such stations.
Provide a sustainable development environment for technology transfer, so that these activities will enhance the national networks and numerous applications with readily available technology
Understand the necessary geodetic requirements of participating national and international agencies.
Assist in establishing in-country expertise for implementation, operations, processing and analyses of modern geodetic techniques, primarily GPS.

Ruth Neilan, acknowledging contributions from Jim Slater

Minutes of the SIRGAS (Sistema de Referencia Geocentrico para Las Americas) committee meeting, held on october 21 and 22, 2002 Santiago, Chile

The president of the Committee highlighted the financial support given by the International Association of Geodesy (IAG), decisive for holding the meeting. The Pan-American Institute of Geography and History (PAIGH), which had approved funds for the project in 2002, could not honor this commitment due to financial difficulties that it is currently facing. Therefore IAG responded to our last minute request, enabling the attendance of eight participants of seven countries of South America, which was decisive for the success of the meeting.

All annexes can be found under http://www1.ibge.gov.br/home/geografia/geodesico/sirgas/principal.htm or http://www.ibge.gov.br/sirgas

1. Status on the integration of the South American countries to SIRGAS (R. Barriga, President of the WG II) (Annex I)

2. Presentation of the SIRGAS 2000 GPS campaign results by the processing centers

2.1 IBGE (S. Costa) (Annex II)

2.2 DGFI (K. Kanniuth)

The coordinates obtained in the individual solutions of each processing center (DGFI with Bernese, DGFI with GIPSY and IBGE with Bernese) shown a consistency between each other of about 5 mm in the horizontal components and 7.5 mm in the vertical component.

Resolution: The SIRGAS Committee decided that the final solution of the SIRGAS 2000 GPS campaign will be generated by the combination of three solutions: DGFI´s, using the Bernese software; DGFI´s, using the GIPSY software; and IBGE´s, using the Bernese software.

3. Combination of the processing centers´ results (H. Drewes/K. Kanniuth/S. Costa)

3.1 Combination strategy and connection to ITRF2000

M. Kumar, from NIMA, presented the following issue: the ITRF solutions are generated using the tide-free system, which is not realistic and contradicts the IAG Resolution 16 of 1983 (Annex III)

Resolution: To keep using the tide-free system in the SIRGAS 2000 results and to formally suggest to IAG to manage with the International Earth Rotation Service (IERS) the solution of this issue.

3.2 Determination of velocities

According to H. Drewes, it is not enough to consider the results of the SIRGAS 1995 and 2000 campaigns for the determination of the SIRGAS stations velocities.

Resolution: The SIRGAS Committee approves H. Drewes´ proposal of considering the observations of permanent GPS stations and of geodynamic campaigns, in addition to the results of the SIRGAS 1995 and 2000 campaigns, for the determination of the velocity field of the South American continent.

3.3 Final results (coordinates and velocities)

Resolution: The SIRGAS Committee accepts in advance as official the final combined results of the SIRGAS 2000 GPS campaign, to be generated by the processing centers in near future.

Resolution: The SIRGAS Committee defines the date of December 20, 2002, as the deadline for the processing centers to release the final combined results of the SIRGAS 2000 GPS campaign.

Resolution: The SIRGAS Committee defines the date of March 28, 2003, as the deadline for DGFI to release the results of the velocity field for the South American continent.

Resolution: The procedures to generate the official results of the SIRGAS 2000 GPS campaign will be described in a final report, similarly to that released during the IAG Scientific Assembly, held in Rio de Janeiro, in 1997.

Resolution: The SIRGAS Committee proposes to include in the SIRGAS 2000 GPS campaign final report a special acknowledgment to the processing centers – DGFI and IBGE – by the enormous efforts carried out and by the excellence of the results obtained.

4. Use of the SIRGAS 2000 final results (H. Drewes, Representative of IAG)

Resolution: The SIRGAS Committee proposes to include in the SIRGAS 2000 GPS campaign final report detailed instructions about how to use the campaign final results.

It was recommended that, for countries that have not adopted yet SIRGAS 1995 as reference system, they should adopt the system based on the SIRGAS 2000 results, reference epoch 2000.4.

5. Presentations of the Working Group III “Vertical Datum” (L. Sanchez, President of WG III, and H. Drewes, Representative of IAG)

5.1 Introduction (Annex IV)

5.2 Urgent need of a modern vertical reference system (Annex V)

5.3 Computation of geopotential numbers and physical heights (Annex VI)

5.4 Reference surface: considerations regarding W0 (Annex VII)

5.5 Future activities (Annex VIII), recommending to countries:

· Geodetic leveling of the SIRGAS2000 stations

· Connection of leveling networks between neighboring countries

· Identification and typing of all leveling lines that connect SIRGAS2000 stations

· Typing of the national leveling networks

· Identification of the network nodes

· UNIFIED determination of the quasi-geoid

· Determination of the sea surface topography (SSTop) (GPS positioning of tide gauges)

The WG III president offered support to the member countries of the SIRGAS Committee regarding the computation of geopotential numbers and help with parallel tasks. It is emphasized that the height differences to be used in computations are the observed ones, WITHOUT any error distribution or adjustment.

6. Continuation of the discussion on the new statute proposal (L. Fortes and C. Brunini)

Resolution: The SIRGAS Committee approves the new project Statute, corresponding to the version originally proposed by the representation of Argentina, with the modifications discussed during the meeting in Santiago del Chile.

With the approval of the Statute (Annex IX), the substitute representative of Argentina in the Committee, Claudio Brunini, proposed the names of Luiz Paulo Souto Fortes, from IBGE/Brazil, and Eduardo Andrés Lauría, from IGM/Argentina, respectively for president and vice-president of the project for the next term (2003-2007). The current president of the SIRGAS Committee will contact all countries embraced by the project in order to confirm the names of the representatives in the Committee and, consequently, to define the necessary quorum for electing the new project authorities. This election will be carried out by electronic mail and the elected authorities will be installed in office in July 2003, at the General Assembly of the International Association of Geodesy.

7. Closing (L. Fortes)

Resolution: The SIRGAS Committee acknowledges the Instituto Geográfico Militar of Chile for the excellent organization of the meeting and for the support to the Committee members.

L. Fortes, IBGE Brazil

Ninth Business Meeting of Ablos, held at the Hydrographic and Oceanographic Department

Japan Coast Guard, Tokyo, October 23-25, 2002

Meeting report is available at: http://www.gmat.unsw.edu.au/ablos/minutes02.pdf

X IAG International Symposium on Recent Crustal Movements, Helsinki, Finland, August 27-31, 2001

The tenth IAG (International Association of Geodesy) International Symposium on Recent Crustal Movements (SRCM) was held in Helsinki, Finland, August 27.-31., 2001. The main organizer of the Symposium was the Finnish Geodetic Institute. Co-organizers were the Department of Geology, University of Helsinki, Department of Geophysics, University of Helsinki, and Department of Surveying, Helsinki University of Technology. Scientific programme was planned together with Prof. Susanna Zerbini, University of Bologna, Italy, the president of the IAG Section V, Commission XIV, Crustal Deformation.

More than 70 participants, and 60 presentations during the symposium show the importance and wide variety of the topic. Natural and athropozenic hazards was one of the topics, as a part of the crustal movements can be violent and rapid, causing both human and materaial losses. Some movements, although slow but still of a great importance, such as the postglacial rebound or the eustatic rise of the sea level, can help us to study and understand global changes, such as warming and its causes, and deglaciation. The proceedings of the Symposium will be published in the Journal of Geodynamics (JoG), an official journal of the European Geophysical Society.

Markku Poutanen, Finnish Geodetic Institute, Secretary of the SRCM symposium

Report of the International Congress on Geodesy and Cartography, Caracas, Venezuela

18-22 March, 2002 (IAG sponsored)

Co-Sponson: Instituto Geográfico de Venezuela Simón Bolívar (DIGECAFA), Dirección de Hidrografía y Navegación (DHN), Fundación Venezolana de Investigaciones Sismológicas (FUNVISIS), Petróleo de Venezuela (PDVSA), Sociedad Venezolana de Ingenieros Geofísicos (SOVG), Instituto Nacional de Canalizaciones (INC), Colegio de Ingenieros de Venezuela (CIV), Asociación Venezolana de Ingenieros Geodestas (ASOVIG),

Organized by: Venezuelan Association Of Geodetic Engineers (ASOVIG)

General Program

Opening Ceremony, Session I and II –Reference Systems, Geoid, Session III and IV–Satellite Techniques, Session V and VI –Geographical Information Systems, Session VII–Cadastre, Session VIII –Interdisciplinary Applications, Session IX–Photogrammetry and Cartography, Session X–Cartography and Remote Sensing, Session XI–Remote Sensing, Session XII–Geodetic Measurements in Engineering

Statistics

There were 72 oral paper presentations from 123 Authors, 62 University students, and 152 registrated participants.

Oral presentations:

In the following, there were presented 72 individual and multinomial papers. The paper titles and their authors are (not in chronological and schematic order):

Acuña (Venezuela), Bosch (Germany): Improving comparisons of satellite altimeter observations and tide gage registrations for unifying height systems in the Caribbean area. Alves, Blitzkow, (Brazil): Modern concepts and techniques of control and forms to monitor tide gage stations with GPS. Alves, Blitzkow, et al. (Brazil): Sea level determination 1831 and 2000 with GPS, leveling and tide gage observations. Arrieche, (Venez): Experiences of hiperspectral remote sensing in the Venezuelan Oil Industry. Azcarate, Martinez, et al., (Venez): Design and application of an interactive system of digital images. Blanco, Gajardo, et al., (Venez): Geotechnical, geophysical and hydraulic studies to define the stability of Mamo Mesa Venezuela. Blanco, Gajardo, et al., (Venez): Observation system of Viaduct No.1 of highway Caracas-La Guaira. Orlando, Barromé, (Venez): Geodetic and instrumental control of the Hydroelectrical Complex of the Lower Caroni River. Buyana, Guevara, et al., (Venez): Methology of Geoid ondulation determination with heterorgenic geodetic data. Clayton, Jacques, et al., (Brazil): Methodology to locate the most favorable areas for installation of small hydropower systems in a GIS environment. Cardozo, Núñez, et al., (Brazil): Orthomosaic generation from a digital, nonmetric camera. Carvalho., et al., (Brazil): Methology for hydraulic works registration of Bahia State, Brazil. Carvalho, et al., (Brazil): Fluvial dynamics of Sao Francisco River using Landsat 7/ETM + images. PimenteL et al., (Brazil): Digital cartography for management of water distribution networks. Pimentel, Ferreira, (Brazil): Teodoro Sampaio and the beginning of systematic cartography in Brazil. Pimentel, Nero, (Brazil): Cartographic documents: Determination of geometric quality in Brazil. Correa E Castro, Blitzkow, (Brazil): Recovery of South American gravity nets by Chile and Paraguay. Daal, Balcázar, et al. (Venez), TREMEL (Germ): GPS Campaign REGVEN 2000. Carvalho et al. (Brazil): Geobotanical analysis of geological structures using hyper spectral images. Cogliano, Galban, et al., (Argentina): First comparison of height networks between Chile and Argentina. Laura Delgado et al. (Venez): Remote Sensing – Digital terrain models and GIS: Tools for Malaria control. Do Nacimiento et al. (Brazil): Morphologic analysis of the Grande River basins as subsidy for ecological zoning using GIS. Dolande, Montezuma, et al. (Venez): Cartographic cover of Esequibo territory by Landsat TM and ETM. Dominguez et al., (Venez): Calibration of position equipments for offshore seismic surveys. Fontes, et al., (Brazil): Use of GIS in management of National Park in Brasilia. Francoso, et al., (Brazil): GIS for historical rescue. Francoso, et.al., (Brazil): GIS en Sao Paulo State. Freitas, et al., (Brazil): Cartographic actualization with IKONOS, using IKONOS 2 satellite for cartographic actualization in maps up to 1:2500. Fuenmayor, et al., (Venez): SIRGAS – REGVEN point densification for PDVSA. Gechele, Nixon, et al., (Venez): GIS implantation by GPS in coastal areas of Maracaibo lake. There were considered Hydro Pro, Pathfinder Office, Auto Cad and Arcview. Gonzalez, Digecafa, (Venez): Evaluation of quick static positioning for medium distances. Guerra, et al., (Venez): The homogeneous treatment unit (UHT), an SIG tool for perforation dispositions.Guevara, et al., (Venez): Evaluation of precision of image orthorectification of IKONOS Satellite in urban areas of Caracas. Guillen, et al., (Venez): System implantation and proof for vehicle control by GPS. Henneberg (Venez): Geodetic measurements of neotectonics and recent crustal movements. Hernandez, (Venez): Evolution and actual situation of Venezuelan geocentric reference system. Hoyer, Hernandez, et al., (Venez): Geoid determination in Venezuela by minimum square collocation. Hoyer, et al., (Venez): GPS measurements processing of REGVEN project. Hoyer, et al., (Venez): RENDON: GPS measurements in the area of the Yacambú-Quibor hydraulic system. Jauregui, et al., (Venez): Elaboration of digital stereo-orthophotos. Liberal, (Venez): Three dimensional geodetic model and GPS application. Lopez, et al., (Venez): Optimization of GPS applications in the Venezuelan Oil Industry. Marquez, Mecinca, (Venez): DIN 18723 and application for certification of theodolites and level instruments Martin, et al., (Venez): Impact of the new official DATUM of Venezuela (SIRGAS – REGVEN ) in geodetic activities of PDVSA. Alves, Pimentel, (Brazil): Digital terrain model. Nero, Pimentel, (Brazil): Map digitalizations: Comparitive studies of methodologies. Ordóñez, et al., (Colombia): Deformation measurements of GALERAS Volcano, Colombia. Ordóñez, et al., (Colombia): GPS measurements for micro gravity studies of Galeras volcano, Colombia. Mora, et al., (Colombia): Satellite geodesy for tectonic deformation measurements in NE of South America. Oropeza, (Venez): Digital rural cadastre of watering systems in Falcón State, Venezuela. Rincon, Et Al., Hoyer, et al., (Venez): Satellite altimeter studies of the Atlantic Front of Venezuela Rios, (Venez): GIS tendency in geography. Rivas, et al., (Venez): GIS for sub terrain installations in urban areas. Rivas, et al., (Venez): Use and methology of multimedia to execute technical evaluation of road communication systems. Rivas, et al., (Venez): Measurements, analysis and composition of the atlas of road systems. Rivas, et al., (Venez): Application of ISO VALUE Lines for residential buildings using a GIS system. Stamato, (Brazil): Is an electronic atlas a geographic information system? Swanston, (Venez): An approximation to a new cadastral registration system. Swanston, (Venez): Quality control of radar orthoimagery. Taylhardat, Hernandez, (Venez): GIS-Exploration processes. Vallee, Parra, (Venez): Cartography of hydrocarbon emanations. PRAOG, TIESZEN, (USA): Development of exploration, access and dissemination of geospace data (clearinghouse) in different Central American countries caused by hurricane Mitch.Vera, et al. (Venez): Geomorphological vision of North and South America. Wildermann, et al., (Venez): Comparison of different height systems in Venezuela. Gavel (USA): Data evaluation for space positioning for oil wells.

Special presentations:

Henneberg, (Venez): Marine Geodesy. Drewes, (Germ): Why do we need a new height system? Guevara, (USA): The Geospace paradigm and its impact on a bearable progress. Rendon, (Venez): The project for modernization of the national seismology network. Drewes, (Germ): The international reference system ITRF and its continental amplification (SIRGAS). Vera, (Venez): Technological promotion – Air transportable remote system for “Alto Resources Venezuela, C.A.” Prelat, (USA): Hyper spectral technology for evaluation of national resources and environment.

Heinz Henneberg, National IAG Representative

Report on IAG 2001 Scientific Assembly of the International Association of Geodesy,

Budapest, Hungary, 2--7 September 2001

by J. Adam and K.-P. Schwarz

It was in September 1906 that the predecessor of the IAG, the 'Internationale Erdmessung', organized its 15^th General Assembly at the Hungarian Academy of Sciences in Budapest. It was 95 years later, in September 2001 that the IAG returned to this beautiful city to hold its Scientific Assembly, IAG 2001, in the historical premises of the Academy. The meeting took place from September 2-7, 2001 and continued the tradition of Scientific Assemblies, started in Tokyo (1982) and continued in Edinburgh (1989), Beijing (1993) and Rio de Janeiro (1997). Held every four years at the midpoint between General Assemblies of the IAG, they focus on giving an integrated view of geodesy to a broad spectrum of researchers and practitioners in geodesy and geophysics. The convenient location of the main building of the Hungarian Academy in downtown Budapest and the superb efforts of the Local Organizing Committee contributed in a major way to the excellent atmosphere of the meeting.

In the opening session of the IAG 2001 Scientific Assembly, participants were welcomed by Attila Mesko, Deputy Secretary-General of the Hungarian Academy of Sciences, Fernando Sanso, president of the International Association of Geodesy (IAG); Klaus-Peter Schwarz, Chairman of the Program Committee and Jozsef Adam, Chairman of the Local Organizing Committee (LOC). The welcome address of the IAG president Fernando Sanso is attached to this report.

As at previous meetings, the scientific part of the program was organized as a series of symposia, which, as a whole, provided a broad overview of actual geodetic research activities. To emphasize an integrated view of geodesy, the symposia did not follow the pattern of the IAG Sections, but focussed on current research topics to which several IAG Sections could contribute. Each symposium had 5 sessions with presented papers and poster sessions on two consecutive days. Since the majority of papers were presented as posters, an effort was made to give ample exposure to this form of presentation. Besides having each poster up for two consecutive days in the main hall of the building, it was also decided that no parallel sessions would be scheduled during the poster sessions. This gave considerable exposure to the poster presentations and led to good interactions between authors and participants.

The scientific program dealt with the following topics:

Symposium A: Fine-tuning Reference Frame Implementation, Convenors: C.K. Shum (USA) and A.H. Dodson (UK)

· A1 Space Techniques: Coordination and Combination Methods, Chair: H. Drewes (Germany), Co-chair: J. Hefty (Slovak Rep.)

· A2 Non-tidal Earth Gravitation and Geocenter Motion, Chair: B.F. Chao (USA), Co-chair: P. Biro (Hungary)

· A3 Regional Reference Networks, Chair: R. Weber (Austria), Co-chair: L.W. Baran (Poland)

· A4 Vertical Datums: Determination Techniques and Unification, Chair: C. Jekeli (USA), Co-chair: J. Ihde (Germany)

· A5 Is there a Need for a Geodetic Datum 2000?, Chair: C. Boucher (France), Co-chair: E. Groten (Germany)

· AP Poster Session, (Responsible: A.H. Dodson)

Symposium B: From Eotvos to Satellite Gradiometry - New Vistas in Measuring and Modeling the Earth's Gravity Field, Convenors: M.G. Sideris (Canada) and B. Heck (Germany)

· B1 Advances in the Theory of Gravity Field and Geoid Determination, Chair: P. Holota (Czech Rep.), Co-chair: A. Marchenko (Ukraine)

· B2 Use of Gravity Data from Earth and Planetary Satellite Missions, Chair: H. Ilk (Germany), Co-chair: M.Petrovskaya (Russia)

· B3 Airborne Gravimetry, Chair: L. Bastos (Portugal), Co-chair: A. Kopaev (Russia)

· B4 Advanced Technologies for High-resolution Global and Regional , Digital Elevation Models (DEM), Chair: P.A.M. Berry (UK), Co-chair: I.N. Tziavos (Greece)

· B5 Advances in Numerical Techniques and Approximation Methods, Chair: R. Klees (The Netherlands) Co-chair: J. Zavoti (Hungary)

· BP Poster Session (Responsible: B. Heck)

Symposium C: Geometry and Beyond - Using Global Navigation Satellite

System (GNSS) in New Ways, Convenors: C. Rizos (Australia) and J. Adam (Hungary)

· C1 Probing the Atmosphere with GNSS, Chair: H. vander Marel (The Netherlands), Co-chair: A. Kenyeres (Hungary)

· C2 Low Earth Orbiter Satellite Missions, Chair: P. Schwintzer (Germany), Co-chair: J.B.Zielinski (Poland)

· C3 New Concepts in Engineering Geodesy, Chair: H. Kahmen (Austria), Co-chair: Á. Detrekoi (Hungary)

· C4 Probabilistic and Non-probabilistic Assessment in Data Analysis, Chair: H. Kutterer (Germany), Co-chair: A. Dermanis (Greece)

· C5 Biases in GNSS Positioning, Chair: M. Stewart (Australia), Co-chair: S. Tatevian (Russia)

· CP Poster Session (Responsible: J. Adam)

Symposium D: Modeling Earth Processes and Global Change

Convenors: C. Wilson (USA) and V. Dehant (Belgium)

· D1 Ocean-Solid Earth Interactions, Chair: R. Gross (USA), Co-chair: P.Varga (Hungary)

· D2 Variations in Earth Orientations, Chair: J. Vondrak (Czech Rep.), Co-chair: A. Brzezinski (Poland)

· D3 Global and Regional Sea-level Changes, Chairs: A. Cazenave (France) and D.P. Chambers (USA), Co-chair: M.Poutanen (Finland)

· D4 Global and Regional Plate Motions and Deformations, Chairs: S. Zerbini (Italy) and C. Wilson (USA), Co-chair: I. Joo (Hungary)

· D5 Satellite Altimetry for Oceanography and Geodesy, Chair: C.Hwang (Taiwan), Co-chair: M.Vermeer (Finland)

· DP Poster Session (Responsible: V. Dehant)

Special Sessions

· E1 Scientific Cooperation in Geodesy and Geophysics in Central and Eastern European Countries (CEEC), Chair: J. Sledzinski (Poland), Co-chair: F. Vodopivec (Slovenia)

· E2 Research Challenges for Young Scientiests, Chair: K.P. Schwarz (Canada)

· E3 Information Session on the New Structure of the IAG, Chair: G. Beutler (Switzerland)

The scientific program of the meeting was organized by the symposium conveners and the chairpersons of the session. The symposium conveners decided on the acceptance of the submitted abstracts and, in cooperation with the session chairs, on the final program. The session chairs took an active role in soliciting papers for their sessions and were responsible for the selection of papers for oral presentation and the review process. In addition, they organized the review process for the topic of their respective session. This was a major job, considering that a total of 126 oral and 254 poster presentations were made. Special thanks are therefore expressed to all symposium conveners and session chairpersons for organizing the symposia and sessions.

For the first time in the history of the General and Scientific Assemblies, two best student paper awards were announced by the IAG, one to the author of a paper presented orally, and the other to the author of a poster paper. The award for the orally presented paper went to Michael Kern of the University of Calgary, Canada, and the award for the poster paper to Suzanne N. Lyons of the Scripps Institution of Oceonography, USA. Congratulations to both of them.

The IAG Executive Committee decided to select about 100 representative papers, for publication in the reviewed IAG/Springer proceedings series. The selected papers were reviewed by the same review process used for the Journal of Geodesy. Special thanks are expressed to all session chairpersons for getting the reviews in under a very tight time schedule. The co-operation of both authors and reviewers in trying to meet the deadlines was highly appreciated. It made the timely publication of these proceedings possible. The volume contains a representative sample of 93 reviewed papers from all sessions, as well as nine papers presented in the special sessions. This volume (number 125) will be available by the end of March. Note that a CD containing all papers that were submitted for publication in time (deadline: November 30, 2001) was issued and mailed already to all conference participants early in February, 2002.

During the IAG 2001 Scientific Assembly, in addition to IAG Bureau and Executive Committee meetings, 21 Special Study Groups, Special Commission, Commission and Ad hoc group specially organized meetings for discussions and exchanges. Furthermore, meetings of the Joint Board of Sister Societes and the Editorial Board of the Journal of Geodesy took place in Budapest.

Full- and half-day excursions were offered for the participants and accompanying persons to explore Budapest and the countryside (Danube Bend and Godollo Palace). A Welcoming Reception at the Picture Gallery Hall of the Academy and an IAG Banquet at the Citadella Restaurant on the top of Gellert Hill were organized for participants and accompanying persons.

In the closing session of the IAG 2001 Scientific Assembly, the IUGG President Masaru Kono addressed the participants. Following that, brief summaries of the symposia were given by conveners (C.K. Shum, B. Heck, C. Rizos and C.R. Wilson). Finally, closing remarks were presented by J. Adam, Chairman of the LOC and Prof. F. Sanso, President of the IAG.

The meeting attracted a larger number of participants (449 registered participants from 54 countries) and papers (380) than previous Scientific Assemblies. This is in part due to the generous financial and promotional support given by a number of agencies. It made the support of students and colleagues from developing countries possible and gave the social events an additional touch of hospitality. Special thanks go to the International Association of Geodesy (IAG), the Hungarian Academy of Sciences (HAS), the European Space Agency (ESA), the US National Aeronautics and Space Administration (NASA), the Jet Propulsion Laboratory (JPL), the Budapest University of Technology and Economics (BUTE), the Eotvos Lorant and Geophysical Institute (ELGI), the Hungarian Scientific Research Fund (OTKA), and the Ministry of Education. IAG, HAS, ESA and NASA are thanked for their financial contributions.

As decided at the last General Assembly of the IAG in Birmingham in1999, a special IAG Council Meeting took place after the conference in order to make a decision on the proposed restructuring of the IAG. The proposal, presented by the chairman of the Restructuring Committee, Gerhard Beutler, and supported by the IAG Executive, was accepted with small modifications.

The responsibility for organizing this conference was shared by the Program Committee (chairman: Klaus-Peter Schwarz, members: Alan H. Dodson, Che-Kwan Shum, Michael G. Sideris, Bernhard Heck, Clark R. Wilson as IAG Section Presidents) and the Local Organizing Committee (chairman: Jozsef Adam, members: Ivan I. Mueller as IAG Representative, Laszlo Banyai, Gusztav Hencsey, Ambrus Kenyeres, Gabor Papp, Viktor Richter, Gyula Toth). The credit for the professional running of the conference goes to the staff of the conference bureau of the Computer and Automation Research Institute of the Academy. Special thanks are expressed to the Head of this Department, Gusztav Hencsey, and to staff member Viktor Richter for their efficient and friendly organization.

Those interested in more details of the program may consult the web site http://www.sztaki.hu/conferences/iag2001. The reviewed proceedings will be published by Springer Verlag and will be available at the end of March 2002.

Geodesy on the Move

Presidential address to the IAG Scientific Assembly in Budapest

F. Sanso

DIIAR, Sez. Rilevamento, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano, Italy.

Ladies and Gentlemen, dear Friends and Colleagues,

it seems yesterday that we were leaving the IUGG General Assembly in Birmingham outlining the work program for the next four years and announcing that we would meet here in Budapest to verify whether we were marching in the right direction.

Six lines have been put down as the main streets along which to develop the IAG action:

· the first, institutional and most obvious is to develop Geodesy as science in itself,

the others are

· to improve the relations with other sciences and their organization,

· to improve the IAG impact in terms of Services towards other sciences and the society in general,

· to improve IAG penetration into the developing countries,

· to improve the internal IAG organization,

· to widen the scientific manpower on which IAG is based.

I will try to review these in short with one warning: this talk has been prepared a few days ago in the Alps while I was in the so-called ``vacations'' and I had with me only little material, so it is based mainly on my memory which is scarce and even fading.

I hope I still have clear the overall design, but I am pretty sure that I am forgetting important names and facts, so please accept my apologies for that and take this presentation more as a collection of examples rather than being exhaustive.

Point 1:to develop geodesy as a science in itself.

I will dwell little on that because this item is maybe more appropriate for the last session of this Assembly, when we will have a more precise overview on what is going on in geodesy and surroundings, yet I cannot refrain from saying at least two small things.

Trivializing, we could say that our job is:

· to survey the earth (and the planets) with new advanced techniques in a consistent worldwide way,

· to develop new methods to describe our measurement models and to analyze the available data both theoretically and numerically, which means qualitatively and quantitatively.

For the first point I would say that what we already have and we already planned to have in a few years, is what we were dreaming of only few years ago.

Just think of the continuous monitoring of GPS permanent stations by IGS, the global survey by SAR of all the continental topography (I am talking of the SRTM mission) as well as the moinitoring of the oceanic surface by the many altimetric missions and, not to be forgotten, the complete imaging of the earth's global gravity field with CHAMP and subsequently GOCE, including its time variations by the GRACE mission. This is really an age of globalization of Geodesy against which none can protest!

As for the second point the production of new ideas in Geodesy is at the same time too narrow (I will talk about that in the meeting with the young geodesists) and too large to be mentioned in detail. I just want to quote the names of Chris Kotsakis and Rudiger Lehman because they share this year the prize for the bast paper award. I believe it is consulating to see that computers have not killed our thinking in Geodesy letting our beautiful tradition of the Hotine, Marussi, Baarda, Moritz and Krarup continue.

Point 2: to improve the relation with other sciences and their organization.

Are we moving in this direction?

· Planetology I would say we are in strict and even improving relation.Last spring I was sitting in a room in Matera, listening to Dave Smith that took the audience on a fly across mountains and channels of Mars, I mean the true topography computed by NASA, not science fiction! We know that a new ``train'' is leaving for Mars under an ESA project, where our last Bomford prize awarde, Veronique Dehant, is playing a very important role. If I can mention it, there is another mission, Mercury orbiter, approved by ESA, where Italian geodesists have the same role too. But let us come to the other geophysical sciences.

· Solid Earth Physics we share the whole subject of geodynamics to which we contribute all the information coming from the ballet of the earth barycenter, the polar motion and the spinning rate as well as the time variations of the first harmonics of the gravity field. This is our contribution to global dynamics, which we primarily provide through the International Earth Rotation Service. To this we have to add the information on plate tectonics, which is basically coming from the IGS international network of GPS permanent stations, jointly with the other space techniques. Not to be forgotten all the other information on crustal deformation and gravity field variations which complete the picture at a local level. On the earthquakes we have important things to say with the new ideas of combining GPS, and SAR information; think of the Colfiorito earthquake in Italy and that of Izmit inTurkey,

· Oceanography we share again a large number of subjects of common interest; our definition of height datum, the geoid, was historically based on the abstract concept of mean sea level and, unfortunately, we are still discussing about this definition. I do not think I need to underline the importance of altimetric satellite missions for both sciences; I just want to mention that still after many years IAG and IAPSO seem to me like two dogs one running after the tail of the other. We believe that from altimetry we can subtract the dynamic height of oceans to get the geoid there to construct global models, the oceanographers believe that we can provide them a high resolution geoid by our global models so that they can constrain the geostrophic part of the motion. It is a little more complicated than that, but only the forthcoming gravity missions will be able to cut this Gordian knot. Certainly the relations between the two associations are excellent: we have joint symposia and a proposal to run a joint Scientific Assembly could come for the next time, even geophysical associates that were thought to be traditionally far from IAG, like the hydrologists or the atmospheric physicists have discovered that Geodesy is useful to them.

Just six weeks ago at the IUGG Executive Meeting H.C. Davies, the president of IAMAS, has claimed that, contrary to all his expectations, he had to admit that important information could come from GPS or SAR sounding of the atmosphere, and he prized us for that.

So this is the traditional line of ``good relations'' with geophysical associations, with which we share the union organization as well as with the other geophysical societies and we have the impression that we are serving well this traditional field of action.

But there is the other side of our life which is the relation of Geodesy to Surveying, Photogrammetry, Remote Sensing, Cartography and so forth, all the more applied and engineering disciplines that were borne as particular techniques, with associations taking care of the relations with the world of professions. They drifted away, maybe too much, particularly across the Eighties and early Nineties, and this has been a mistake which our executive has tried to counteract by increasing the contacts and the joint activities with FIG, ISPRS and so on. We had joint symposia, schools, and study groups and not only because we think that we have something to teach, but also because we have something to learn. I am thinking for instance of a nice Symposium on Non-standard Non-probabilistic Methods organized in Zurich by Kutterer (SSG 4.190) together with Alessandrio Carosio who's specialty is GIS theory.

We should never forget that it is in IAG genome to be an interface between geosciences and engineering applications, and whenever we forget it we loose as a science and as an organization.

Point 3: to improve the IAG impact in terms of Services towards other sciences and the general society.

I already mentioned the fantastic work performed by the International Earth Rotation Service and the International GPS Service; they are based on a very large international cooperation and give to IAG quite a substantial contribution in the effort of maintaining its outstanding position among geosciences.

It is incredible that, in spite of the continuous threat of the supporting organizations to cut their budget, they have always been able to evolve facing new challenges and providing new products of larger and larger utility.

We would like to be more powerful and authoritative to say to the supporters that they have to continue their effort because it is a honour to be able to serve such a large community in such a good manner! Nor one should forget the relatively new Services like the Laser Ranging Service and the VLBI Service, who play specific essential roles within the same general subjects. Nor I want to forget the Services related to the gravity field like the glorious Bureau Gravimetrique which, together with the International Geoid Service and the International Center for Earth Tides, will join into a new International Gravity Field Service, already here in Budapest; this also with the support of new centers provided by NIMA and GFZ.

To close this point let me at least mention two Services with a clear strong interdisciplinary character: the Permanent Service for the Mean Sea Level and the Bureau International des Poids et Mesures (Time section).

I will explain in a few minutes the enhanced role that Services will play in IAG structure.

Point 4: to improve the diffusion of IAG organization into Developing Countries.

This is not a ritual statement that we repeat every time to keep our soul free of any sense of guilt.

This is a real line for our organization and we proved it by stimulating important projects of international cooperation.

Let us think for instance of SIRGAS and then to the many scientific activities in South America, including the choice of bringing our Scientific Assembly in Rio. We have now a very active South American community which is showing everywhere at the international level. Similar success we had in the South-East Asia Pacific area, where not only our Services and, for instance, International Schools have done very well but also the development of IAG has been boosted by leading nations of the area like Japan, China, Australia.

Nevertheless we always had problems with the African continent.

Despite the historical enterprise of ADOS, despite the many bilateral contacts, we never had a real IAG organization there. At least till recently. However, thanks to the efforts of our Commission X (on Global and Regional Geodetic Networks) and XIV (on Crustal Deformation), as well as of the action of IGS for the full internationalisation of the Earth Reference Frame and our Committee on Developing Countries, we finally see a centripetal motion in Africa around geodetic themes.

In particular, from seven to eight nations in South Africa and six nations in North Africa are setting up joint international geodetic structures under the auspices of IAG and of the Organization Africain de Cartographie et Teledetection.

It was the end of May when I was sitting in Algiers in a room with 150 African colleagues for the Duexieme atelier nord africain de geodesie. We only need to improve our efforts there because we are getting a very positive response; only we still have to think a little bit of the linguistic barrier, but I believe this will be quickly overcome with younger generations.

To achieve that, these nations need support and for sure IAG has not the possibility of financing projects. However, I am proud to say that most of our budget goes to support travels to allow people from developing countries to participate in international meetings. This is a policy with general consensus but we have to acknowledge the particularly firm action of our Secretary General in this direction.

Point 5: to improve the internal IAG organization.

It is not a mania of esthetic order, but the response of a living organism to its needs of growth.

To accomplish what we have illustrated we need:

· a swifter structure in IAG where people from our or other disciplines, particularly young people, could easily find their place if they are interested.

This implies reducing the number of layers and bureaucracy in IAG;

· a structure where Services would be more free to act, to set up projects, schools, to penetrate into new nations on behalf of IAG by contacting the national agencies and, more generally, the users of geodetic products, by affiliating them directly and giving them an international stage where to report their new findings;

· a structure where developing countries could better find scientific support to finally stand on their own legs and contributing back to the IAG evolution.

Along these lines new statutes and bylaws have been elaborated by a commission under the leadership of our Vice President, Gerhard Beutler. They have been discussed by the Executive and then publicized through the IAG home page. I am glad to say that we received reactions, comments and suggestions very sensible and appropriate.

So a final version will be submitted to the IAG Council, which is holding an extraordinary meeting here in Budapest and, in case of approval, they will be already applied in Sapporo at the next IUGG General Assembly.

Also, in this way we feel we have accomplished a mandate by our Assembly in Birmingham, to widen the scientific manpower on which IAG is based. While closing the XXII General Assembly I said to the audience “Come all several and plenty, come to IAG in Budapest and bring your best piece of geodetic work”.

Dear friends, this is the Fifth scientific Assembly, after Tokyo, Edinburgh, Beijing and Rio.

In Tokyo we had 360 people and 177 papers, in Edinburgh 360 and 250 papers, in Beijing 350 people and 295 papers, in Rio 350 people and 279 papers; in Budapest we have up to 3 days ago 472 registrations and 427 papers, and I believe that counting the last minute registration we will end up well over 500!

I do not want to be triumphal but I think I am allowed to congratulate with you, because you are moving exactly in the direction you have chosen in Birmingham and though the way is still long I want to say welcome Geodesy to open your march.

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IAG/IAPSO Joint Working Group on

Geodetic Effects of Nontidal Oceanic Processes

Recognizing the important role that nontidal oceanic processes play in Earth rotation dynamics, an IAG/IAPSO Joint Working Group on Geodetic Effects of Nontidal Oceanic Processes was formed at the XXII General Assembly of the IUGG in Birmingham. The objective of this IAG/IAPSO Joint Working Group is to investigate the effects of nontidal oceanic processes on the Earth’s rotation, deformation, gravitational field, and geocenter, and to foster interactions between the geodetic and oceanographic communities in order to promote greater understanding of these effects. A meeting of this IAG/IAPSO Joint Working Group, its fifth, was held on April 7, 2003 in Nice, France in conjunction with the 2003 Joint Assembly of the European Geophysical Society (EGS), the American Geophysical Union (AGU), and the European Union of Geosciences (EUG) during which presentations were given by R. Gross, and O. de Viron.

R. Gross described the International Earth Rotation Service (IERS) Special Bureau for the Oceans (SBO). The IERS Special Bureau for the Oceans is one of eight Special Bureaus of the IERS Global Geophysical Fluids Center (GGFC) which was established on January 1, 1998 in order to help relate dynamical properties of the atmosphere, oceans, mantle, and core to motions of the Earth, including its rotation. In particular, the IERS Special Bureau for the Oceans is responsible for collecting, calculating, analyzing, archiving, and distributing data relating to nontidal changes in oceanic processes affecting the Earth’s rotation, deformation, gravitational field, and geocenter. The oceanic products available through the IERS SBO are produced primarily by general circulation models of the oceans that are operated by participating modeling groups and include oceanic angular momentum, center-of-mass, bottom pressure, and torques. Through the IERS SBO web site at <http://euler.jpl.nasa.gov/sbo>, oceanic data can be downloaded, software to compute the oceanic angular momentum, center-of-mass, and bottom-pressure from the modeled temperature, salinity, and horizontal velocity fields can be obtained, and a bibliography of publications pertaining to the effect of the oceans on the solid Earth can be retrieved. Currently, three different oceanic angular momentum data sets and two different oceanic center-of-mass data sets are available. Links are also provided to related web sites from which observed and modeled ocean-bottom pressure data sets are available. The IERS SBO is one possible source of data that can be used by the IAG/IAPSO Joint Working Group in their investigations of the geodetic effects of nontidal oceanic processes. O. de Viron described the nontidal effect of the oceans on geodetic parameters using the CLIO model. The Coupled Large-scale Ice Ocean (CLIO) model is a baroclinic Boussinesq model developed at the Universite Catholique de Louvain in Belgium to study ocean dynamics and, in particular, the interaction between sea-ice and the oceans. It has been adapted in order to account for the oceans' response to atmospheric pressure forcing. The results presented at the meeting come from an 11-year simulation spanning 1992 to 2002. The model is forced using NCEP reanalysis data: 6 hourly pressure and friction drag, daily surface air temperatures and wind speeds, and monthly climatologies of relative humidity, cloud fraction, precipitation rate, and river

runoff. It was shown that the model is adequate to study the oceans' effect on geodetic quantities: the derived oceanic angular momentum (OAM) is similar at low frequency to other OAM series and the omparison between the model-derived ocean-bottom pressure is similar to the few measurements that are available. On the other hand, the model seems to be overreacting by a factor of two at periods less than 5 days. This is still under investigation.

R. Gross discussed the oceanic contribution to Earth rotation changes using the ECCO model. As part of JPL's participation in the Estimating the Circulation and Climate of the Ocean (ECCO) consortium, ocean models are being used to simulate the general circulation of the oceans. Oceanic angular momentum computed from these models have been compared to observed changes in the Earth's rotation during 1980-2000. Although nontidal changes in the Earth's length-of-day on time scales of a few days to a few years are primarily caused by changes in the angular momentum of the zonal winds, other processes such as oceanic current and bottom pressure changes can be expected to cause the length-of-day to change as well. On intraseasonal time scales, atmospheric surface pressure, oceanic currents, and ocean-bottom pressure are found to be about equally effective in causing the length-of-day to change, while upper atmospheric winds are found to be less effective than these mechanisms. On seasonal time scales, the upper atmospheric winds are more important than the sum of currents and bottom pressure in causing the length-of-day to change, and, except at the annual frequency, are even more effective than surface pressure changes. On interannual time scales, oceanic currents and bottom pressure are found to be only marginally effective in causing the length-of-day to change. For polar motion, a remarkable 70% of the observed polar motion excitation variance during 1993-1999 is explained by the sum of atmospheric and oceanic angular momentum, with the coherence between the observed and modeled excitation being dramatically improved across a broad frequency band when the angular momentum of the oceans is added to that of the atmosphere.

Meetings of the IAG/IAPSO Joint Working Group on Geodetic Effects of Nontidal Oceanic Processes have been held during the past four years in conjunction with major conferences in order to foster interactions on this topic between the geodetic and oceanographic communities. A report of the activities of the Joint Working Group will be presented at the XXIII General Assembly of the IUGG to be held in Sapporo, Japan during June 30 to July 11, 2003. In order to receive a copy of this report, please contact Richard Gross at <Richard.Gross@jpl.nasa.gov>.

R. Gross

Report of the International Workshop on Satellite Altimetry for Geodesy, Geophysics and Oceanography: Summer Lecture Series and Scientific Applications, Wuhan, China September 8 to 13, 2002.

The www address is http://space.cv.nctu.edu.tw/altimetryworkshop/altimetry.htm.

The workshop was hosted by the Wuhan University with Dr JC Li as the chair of the LOC. The scientific program was organized by the Scientific committee chaired by C Hwang. The workshop’s aim is to offer free lectures on various aspects of altimetric research for beginners and for advanced researchers, and to provide a forum for presentations and discussions of latest results in satellite altimetry.

A total of 60 abstracts were received and 65 people participated in this workshop. These participants are from Austria (2), Australia (1), Canada (1), China (26), Czech Republic (1), Denmark (2), France (1), Germany (2), Italy (2), Japan (1), Korean (2), Netherlands (2), Taiwan (13), UK (1), and USA (7).

On Sep 9 and 10, 2003, five three-hours lectures were delivered by CK Shum (principles of altimetry), K. Matsumoto (ocean tides), O.B. Andersen (marine gravity and geoid), P. Berry (waveform retracking) and DT Sandwell (bathymetry estimation). Three keynote speeches were delivered by W Bosch (geodetic applications), A Cazenave (sea level change) and LL Fu (ocean dynamics from altimetry).

The scientific sessions began on Sep 11 and contains Sessions G1 (chaired by C Zhao), G2 (W Bosch), G3 (EL Mathers) , GO1 (H Schuh), GO2 (J Klokocnik), GO3 (C Hwang), O1 (C Zuffada) and O2 (HZ Xu) with 37 papers presented.

Chair of Org committee: C. Hwang, Taiwan.