Many drought monitoring and early warning systems use soil moisture anomalies to display warnings of drought hazard. As few soil moisture measurements are available and drought is a large-scale phenomenon, these systems often rely on soil moisture modeled with hydrological models or land surface models coupled to climate models. A new such system is the Drought Monitor by the UfZ Helmolz Centre, Leipzig (http://www.ufz.de/index.php?en=33328). Independently, a wealth of drought impact reports, including many impacts on agriculture, have been collected and categorized within the European Drought Impact report Inventory (EDII) here in Freiburg.
The aim of the thesis is to use the drought impact reports to validate and potentially optimize the German Drought Monitor, by comparing the data of the two during past drought events.
Model output variables from the hydrological model underlying the Drought Monitor (mainly soil moisture, but possibly others such as runoff, storages, etc.) will be used in close cooperation with Luis Samaniego at UFZ Leipzig. The EDII data needs to be post-processed to create a validation dataset for the purpose. Objective measures need to be calculated to compare the two. Depending on the outcome, possibly extra model runs could be made or different drought warning levels or drought indices derived that are particularly suitable to certain regions or impacts.
Analysis of large datasets, combining continuous modeled hydrological data with categorical impact observations.
Kerstin Stahl, Luis Samaniego (UFZ Leipzig)
Luis Samaniego, Rohini Kumar, and Matthias Zink, 2013: Implications of Parameter Uncertainty on Soil Moisture Drought Analysis in Germany. J. Hydrometeor, 14, 47–68. doi: http://dx.doi.org/10.1175/JHM-D-12-075.1
Stahl, K., Kohn, I., Blauhut, V. , Urquijo, J., De Stefano, L., Acácio, V., Dias, S., Stagge, J. H., Tallaksen, L. M., Kampragou, E., Van Loon, A. F., Barker, L. J., Melsen, L. A., Bifulco, C., Musolino, D., de Carli, A. , Massarutto, A., Assimacopoulos, D., Van Lanen, H. A. J.: Impacts of European drought events: insights from an international database of text-based reports Nat. Hazards Earth Syst. Sci., 2016; 16: 801-819.http://www.nat-hazards-earth-syst-sci.net/16/801/2016/nhess-16-801-2016.pdf