Report of APSG Meeting

The Third Plenary APSG meeting was held in Tsukuba, Japan on October 20 in conjunction with the International Symposium on GPS. A Meeting of the Management Board was held on October 21.

Planary Session - October 20

Shuhua Ye reviewed the program history, objectives, and organization. Mike Pearlman reported that the APSG proposal submitted in response to the NASA Solid Earth and Natural Hazards Solicitation NRA-98-OES-13 has been accepted. The proposal, submitted from the Shanghai Astronomical Observatory with Dr. Shuhua Ye as Principal Investigator and 80 co-investigators from 14 countries, requested NASA recognition of APSG and continued NASA support for measurement networks, data archiving and analysis, and scientific interpretation. No funds were requested. The IAG Commission XIV on Crustal Deformation, now chaired by Susanna Zerbini, is presently organizing its Subcommissions, one of which will be WEGENER. An APSG Subcommission will also be invited to join.

John Manning reported on Regional Coordination of APSG GPS Projects in 1998. APSG is attempting to harmonize results from the various campaigns in the region by developing a cooperative linking strategy of interchanging data from a small number of key sites from each campaign so that results can be integrated into a common reference frame. Some success was achieved with coordination of observations, and data from most of the campaigns has been made available. Negotiations continue with the other groups. Data from the cooperative sites is available on CD-ROM from AUSLIG for APSG researchers. APRGP 97 and 98 data sets are available through AUSLIG. APRGP 99 is scheduled to take place in early November. John also reported on the establishment of a meta-data base at AUSLIG for the permanent observatories in the Asia Pacific region. A broad description of the campaigns will also be included.

Short reports were presented from the Science Working Groups. Jeff Freymueller, and Jinwei Ren, representing SWG 1, reported that the Crustal Motion Observation Network Of China (CMONOC) now has 25 permanent GPS sites, 56 sites that are resurveyed annually, and about 1000 sites that will be surveyed on a decadal basis. Geological teams have also been working on field investigations of tectonic structure in relevant areas. GPS sites at Shanghai, Wuhan, and Kunming are routinely providing data to the IGS. Sites at Beijing and Changchun might be other candidates since they are collocated with SLR. Makoto Murakami and Trevor Baker gave brief overviews of the objectives and plans for SWG2 and SWG3.

For the Radio Techniques Measurement Panel, Ruth Neilan stressed that the APSG CORE Network was compatible with IGS needs and that IGS services could strengthen APSG infrastructure. IGS will archive any "reasonable" GPS data that is submitted in proper format thereby offering data archiving facilities. Ruth also commented on the growth of GPS stations in the Asia Pacific region but stressed that the real issue was communications and that it could only be solved with money.

John Manning presented the current status of SLR and the establishment of the International Laser Ranging Service. Once again it was stressed that we should take advantage of established capabilities. John recommended that we disband the SLR Measurement Panel and rely instead on the ILRS or WPLTN, perhaps seeking an ILRS representative to act as liaison with APSG.

Taizoh Yoshino reviewed VLBI activities within the region. Of interest was the possibility of a VLBI program in South Korea.

Zuheir Altamimi reporting for Procedures and Standards pointed out that the ITRF is now being used for a wide range of applications and encouraged all stations and analysis centers to contribute to the ITRF 2000. Stations must have at least 3 years of observations and satisfy spacing requirements specified in the Report from the IGS 89 Workshop. Submissions to ITRF must be unconstrained solutions, in SINEX format with fixed TRF.

Zuheir also stressed the need to include GPS measurements near existing tide gauges.

Ewald Reinhart reported that BKG has received proposals from India, Argentina, and South Africa in response to its solicitation for the operation of TIGO. With placement of NASA SLR systems in Argentina and South Africa being imminent, the India option is probably of great interest. A decision will be made in the second quarter of 2000.

Shuhua Ye reported that there are five coastal tide gauges in China; the position of each has now been measured with GPS. She also mentioned that there is a network of absolute gravity sites in the region. Houtze Hsu is considering a proposal for an absolute gravity campaign in the Pacific Rim region. The Hong Kong Polytechnic University Group has studied sea-level change in Hong Kong area; the study will be extended to Macao and the SE coast of China.

The Call for Participation in APSG was issued at the beginning of September. Responses were requested by October 1, but additional responses are welcome. Proposals were solicited for stations, operations center, regional data and metadata centers, analysis and associate centers, and a Central Bureau.

Current thinking about the APSG organization and the additional of a Program Management Committee was discussed.

Meeting-wide discussions elicited the following comments from the audience;

1. The importance of working with the International Lithosphere Service and the Seismological community is very important; we should not work in a vacuum;

2. The connection with "hazards" needs clarification; the development of strain maps as inputs for seismologists would be a very important contribution;

3. The design of networks for strain measurement needs to be developed on a step-by-step basis to ensure its relationship with the "hazard" we are trying to understand (improperly designed networks could yield little or nothing);

4. Release of data is a big issue in the region; anything APSG could do to help would be useful;

5. In the process of working with regional networks, APSG should consider the IGS experience with EUREF where the densification of ITRF is undertaken through national networks and regular GPS solutions are integrated by BKG to create regional solutions and submitted to the IGS system through Tom Herring. WEGENER also uses data from the regional framework as required for specific scientific projects;

6. In seeking participation from existing GPS sites, recognize that National Agencies need their geodetic sites to be referred to the ITR; cooperation may be helpful to them.

Management Board Meeting - October 21

Responses to Call for Participation

All of the proposals submitted in response to the APSG Call for Participation were accepted. The proposal for the Central Bureau from the Shanghai Astronomical Observatory in cooperation with the Hong Kong Polytechnic University included Cheng Huang as Director and Xinhao Liao as Secretary. Additional proposals, in particular those from additional stations in the region, will be encouraged.

ACTION: Dr. Ye will send out letters of acceptance.

Management Board

The Management Board was established to provide national representation to the APSG. Recognizing the work underway in the region by German investigators, it was suggested that a representative from Germany, perhaps from GFZ, be added to the Management Board.

ACTION: Dr. Ye will contact Chris Reigber for a recommendation.

Program Management Committee

It was agreed that we should establish a Program Management Committee to take a broad scientific view and to help foster communications, cooperation, and synergies among projects and colleagues working in the region. The Committee should: keep track of projects underway and planned, maintain lists of key people and contacts, help coordinate projects, and encourage joint results. The Committee should include two conveners from each of the Science Working Groups, some representation from the Technical Advisory Panel (as deemed necessary by the SWG conveners), and some administrative support from the Central Bureau. The conveners should select their own chairperson.

ACTION: Dr. Ye will contact the SWG Conveners and ask for their participation.

Technique Advisory Panel

It was agreed that since international services such as the IGS, ILRS, IVS, IERS, etc, are now well established, we should take advantage of those resources wherever possible rather then continue to maintain our own Measurement Technique Panels. APSG should seek a liaison with the existing services including IAGP, ILS, etc, who could bring both expertise and a close link with APSG. These liaisons would constitute a Technical Advisory Panel that would support the Program Management Committee. The Technical Advisory Panel would select its own chairperson. The Central Bureau would provide administrative support. Representatives from the Technical Advisory Panel would serve on the Program Management Committee at the discretion of the Committee

Ruth Nielan (IGS), Chopo Ma (IVS), and Mike Pearlman (ILRS) have agreed to serve on the Technical Advisory Panel.

ACTION: Dr. Ye will contact other services to seek their participation.

Infrastructure Support

The APSG sites, operations centers, regional data centers, analysis centers, and Central Bureau will provide infrastructure support. However every effort will be made to avoid duplication of services that can be provided elsewhere.

The new Central Bureau at Shanghai will establish a metadata base for all sources of relevant data within the region. They should coordinate with metadata base activities at AUSLIG to avoid duplication.

Participants were reminded to visit the APSG website at:


Arrangements will be made for a special APSG Session at the Western Pacific Geophysics Meeting 2000 in Tokyo on June 27 - 30, 2000. Meetings of the Management Board and the Program Management Committee will also be scheduled. Concern was expressed that the APSG meeting could be diluted in such an event, but it was difficult to schedule a dedicated meeting at a separate time.

It was suggested that at some point, the individual Science Working Groups might want to meet to provide a more focussed venue.


It was suggested that we consider an APSG Special Publication in a noteworthy journal as a means of focussing interest for both contributors and readers.

Preparation of Meeting Report

Mike Pearlman will draft a report on the Meetings at Tsukuba. The Central Bureau will collect copies of the viewgraphs presented at this meeting for circulation with the meeting notes.

Ye Shuhua
John Manning
Mike Pearlman
Makoto Murakami

Session 1
Session 2
Session 3
Session 4
Session 5
Session 6
Session 7
Session 8
Session 9
Session 10
Session 11
Session 12
Session 13
Session 14