As opposed to drought, floods are readily identifiable and relatively short-lived events, caused by “an excess of water mostly but not exclusively from rivers” and described as “the temporary covering by water of land not normally covered by water” (European Union, Directive 2007/60/EC).

The relatively short-lived nature of flood events calls for a higher than monthly to weekly temporal resolution of the GRACE-based gravity field solutions in order to adequately capture the flood water dynamics at hand.

As mentioned before, both GNSS and Hydrology time series will be used for validation within the EGSIEM project. During the last months, we have already set up part of the GNSS and Hydrology processing on our server.

For the GNSS part, we have finished the automatic pre-processing of the latest existing global daily GPS time series from JPL and SOPAC (ftp://garner.ucsd.edu/pub/timeseries/measures/ats/Global). We use the global cleaned and detrended daily time series, among which the mean, trend, coseismic and seismic jumps (including offset and deday) are already removed.

Here you can view our third Newsletter published in October 2015 simply click on the links below.

We would love to hear any feedback you might have on the content, so please do contact us if you have any comments!

Newsletter No. 3 (Link)

on Global Gravity Field Modeling from Satellite-to-Satellite Tracking Data 4-9 October 2015, Bad Honnef, Germany

The autumn school with the subject ‘Global Gravity Field Modeling from Satellite-to-Satellite Tracking Data’ was held from 4th to 9th October 2015 in Bad Honnef, Germany. The main goal of the school was to provide the participants with a good theoretical and practical knowledge about the gravity field recovery from satellite-to-satellite tracking data. The core topics of the autumn school and their corresponding lecturers were:

The EGSIEM team is delighted to announce the arrival of our project brochure, you can view it by clicking on the following picture or link;

EGSIEM Brochure (Link)

Since the establishment of DLR-ZKI (Center for Satellite-Based Crisis Information), the development of EO-based methodologies for the rapid mapping of flood situations has been of major concern. This is can be especially contributed to the fact that inundations constitute the majority of all ZKI activations as well as activations of the International Charter ‘Space and Major Disasters’. These requirements have led to the development of dedicated SAR-based flood mapping tools which have been utilized within numerous rapid mapping activities of flood situations since 2008.

Various GRACE monthly gravity field solutions have been produced by several institutions including the official GRACE data processing centers, GFZ, CSR, and JPL, and additional processing centers such as AIUB, GRGS, and ITSG at TU Graz. To make use of the solutions from different processing strategies together, we can combine the individual solutions.

Until now, monthly GRACE gravity field models have been available with a time delay of about two months, which just allows for the ‘confirmation after occurrence’ and to assess the severity of a hydrological extreme event. The main goal of the EGSIEM NRT service is to reduce this latency significantly to a maximum of five days and to provide daily gravity field models on a regional to global scale. The EGSIEM NRT service will be implemented and operated by the GFZ (German Research Center for Geosciences) and Graz University of Technology (TUG), plausibility tests for the daily solutions will be performed at the University of Luxembourg.