[IGSMAIL-5011]: IERS GGFC Special Bureau for Loading status

[Hans-Peter Plag]

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IGS Electronic Mail      13 Sep 14:25:35 PDT 2004      Message Number 5011
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Author: Tonie van Dam, Hans-Peter Plag, Halfdan P. Kierulf


The products web page of the IERS GGFC Special Bureau for Loading has 
been upgraded and is now delivering on a routine basis 6-hourly products 
related to the 3-D displacement field of the Earth surface due to air 
pressure loading. These products are available at
http://www.sbl.statkart.no/products/operational .
The following is currently available:

- Global Grids: The global grids with a spatial resolution 2.5 x 2.5
   degrees are computed every 12 hours on the basis of the ECMWF mean sea
   level pressure data for the current hour, the six hourly prediction
   and the 12 hourly prediction. Air temperature is used to compute the
   pressure anomaly at the Earth's surface using ETOP5 to determine the
   topography. Latency for the grids is approximately 17 hours.
- Time series: Time series for individual stations. In order to ease
   access, these stations are grouped, with the groups including all ITRF
   stations for each individual technique, the EUREF stations, and the
   ESEAS stations.
- Points: Six-hourly files with loading predictions for selected points.
   The points are corresponding to several groups of stations. Currently
   the station groups are the same as for the time series.

More information on the products is available on the web page.

We invited particularly the Analysis Centers to provide feedback on the
quality of the 'operational' products and their usefulness in terms of
format, availability, groupings a.s.o. If additional products or similar
products in different forms would be more appropriate for future use in
operational analyses, we would appreciate to learn about this.

We also would like to inform you that additional products have been
added to http://www.sbl.statkart.no/products/research and the available
products have been updated in terms of time interval covered. The main
products there are historical grids as well as time series of
loading-induced displacements for all ITRF sites and selected other
networks. Again, feedback on the quality and usefulness of these
research products is most welcome.

If there are other station networks that should be included in the
processing, please, feel free to contact us. However, it has to be
emphasised that the routine products produced on the basis of the
ECMWF near-real time data are provided for research purposes mainly
within the ITRF community, only. If a network is suggested for
inclusion, we would need a proposal describing the research
to be done based on the routinely provided products.

We hope, the service of the SBL is of use for you. Questions directly
related to the operational processing should be directed to
Halfdan P. Kierulf (halfdan.kierulf at statkart.no). Questions related to
other issues of the SBL should be sent to both Tonie van Dam
(tvd at ecgs.lu) and Hans-Peter Plag (hpplag at unr.edu).