Wolfgang Wagner works at the Vienna University of Technology. His main research interest lies in physical modelling and geophysical parameter retrieval from active remote sensing data. In particular, he has been involved in the initiation and development of operational ASCAT soil moisture data services.
Why is this a good time to have a combined H-SAF and HEPEX workshop?
The H-SAF and HEPEX workshops on coupled hydrology are an excellent opportunity to exchange the latest information and science results about the use of EUMETSAT satellites for hydrological applications. Particularly exciting for us has been the rapidly increasing use of ASCAT soil moisture data for runoff prediction and drought monitoring over the past few years. Initially, the coarse resolution of the ASCAT data of about 25 km and their short penetration depth into the soil appeared to be a problem. But fortunately, hydrologists have come up with genuine solutions that allow the ASCAT soil moisture data to be used either directly as input into their models or via data assimilation schemes. In terms of soil moisture data assimilation, ECMWF is one of the leading organizations worldwide, having inspired many hydrologists to adopt data assimilation techniques in their work as well.
What are the new areas of research that are likely to have a big impact?
On top of the increasing use of ASCAT soil moisture data, some very new research suggests that the ASCAT can even be used to estimate rainfall. The basic idea of this approach is to regard the soil as a natural rain gauge and to invert a land surface model to estimate rainfall from the observed soil moisture increments. The method tends to detect too many small rainfall events due to the noise in the ASCAT soil moisture data, but do seems able to estimate accumulated rainfall over a few days very well. Now hydrologists have started experimenting with using both soil moisture and rainfall data from ASCAT for improved runoff prediction, with very encouraging results. This is further motivation for our H-SAF soil moisture team to keep on improving the quality of the ASCAT data services, encompassing such important issues such as improving the error characterization, better modelling of vegetation, and eventually to deliver a higher resolution data product with 10 km.
Notes
The HEPEX mission is to demonstrate the added value of hydrological ensemble predictions (HEPS) for emergency management and water resources sectors to make decisions that have important consequences for economy, public health and safety.
H-SAF (EUMETSAT Satellite Application Facility on Support to Operational Hydrology and Water Management) provides new satellite-derived products from existing and future satellites to satisfy the needs of operational hydrology and perform independent validation of the usefulness of the new products.