[IGSMAIL-4067]: TIGA: Data availability

[Tilo Schoene]

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IGS Electronic Mail      03 Sep 01:17:05 PDT 2002      Message Number 4067
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Author: Tilo Schoene

Dear Colleagues,

With this e-mail the TIGA project announces the availability of the
first set of reprocessed data products (SINEX files) for the continuous
monitoring of GPS points at Tide Gauges (cGPS at TG). The solutions can be
accessed through the TIGA WEB page (http://op.gfz-potsdam.de/tiga) or by
anonymous access to the FTP server at GFZ Potsdam. As soon as more
individual solutions become available a combination solution will be
provided. This is expected to happen at the end of 2002.

I would like to take this opportunity to shortly review the activities
of the TIGA project.  It has been awhile since the TIGA Call for
Participation (CfP) was issued [IGSMAIL-3370]. The Pilot Project (PP)
committee got very positive replies and a good response. By the end of
2001 fifteen proposals were positively reviewed by the PP committee and
the IGS Governing Board. Actually TIGA has 16 accepted proposals
covering all aspects of TIGA. Just to briefly review the TIGA-CfP, the
PP is divided into four main components. TIGA Observing Stations (TOS)
are the primary part of the project. A prerequisite for becoming a TOS
is the open data policy on GPS, tide gauge and leveling data. The GPS
data and additional metadata is stored at the TIGA Data Centers (TDC).
We have a good set of centers, which have committed themselves to accept
the data with varying latency and on different media. TIGA Analysis
Centers (TAC) are divided into three different classes; Type-I centers
will not only process data with a very high latency but also reprocess
older data. Type-II centers will supplement the high latency processing,
while Type-III centers will provide short latency analyses. Consequently
TIGA Associate Analysis Centers (TAAC) primarily will analyze the TAC
solutions and compare the solutions also with externally estimated
vertical motion rates. For more in-depth information see the TIGA home
page at http://op.gfz-potsdam.de/tiga/.

The first half-year of 2002 was very busy with the establishment of some
TIGA components, e.g. the establishment of TDC's, or the setting up the
processing chain at the TAC's. While this process is still in progress
more solutions will become available. The TAAC's and 'TAC's have
discussed the processing strategy and agreed on a minimum of common
standards. The most important agreement was on the latency of the TAC-I
and TAC-II processing. The accepted 460-day latency allows also the very
remote stations in Antarctica to submit their data.

The main problem of the TIGA project at the moment is the TOS situation.
While about 180 tide gauges exist with a GPS station in less than a few
kilometers distance, only 23 stations have been submitted to TIGA.
Especially for North and South America, and Asia no station is submitted
so far.

TIGA is a unique possibility to re-process cGPS at TG data. Moreover this
project is a major contribution to the climate change related question
about sea level change. I would like to ask you again for you
participation and contribution by taking responsibility for TOS
stations. If you are in some way responsible for a cGPS station near a
tide gauge, or vice versa, a reply would be greatly appreciated.

With my best regards
Tilo Schoene

-- 
Tilo Schoene
GeoForschungsZentrum Potsdam (GFZ), Division 1, Section 1.2

c/o DLR Oberpfaffenhofen,         D-82234 Wessling, Germany
mailto:tschoene at gfz-potsdam.de    Tel: +49-(0)8153-28 1391
http://op.gfz-potsdam.de/         Fax: +49-(0)8153-28 1207