This seminar will present two studies focused on the assimilation and evaluation of soil moisture observations retrieved from the passive microwave Advanced Microwave Scanning Radiometer (AMSR-E) and the active microwave Advanced Scatterometer (ASCAT) sensors.
The assimilation of passive and active microwave soil moisture data has not yet been directly compared, and the first study compares the assimilation of ASCAT and AMSR-E soil moisture data into NASA's Catchment land surface model, using an Ensemble Kalman Filter. The impact of each assimilation experiment is assessed based on the anomaly time series correlation-coefficient with in situ observations of surface and root-zone soil moisture from the US and Australia. The skill gained from assimilating either or both data sets is evaluated by land cover type, and the minimum observation skill required for the assimilation to benefit the model is demonstrated.
To date, remotely sensed soil moisture observations have typically been evaluated by comparison to in situ soil moisture data, as in the study above. This approach is possible only at a limited number of locations, and the results are contaminated by representivity errors between the point-based in situ and coarse-scale remotely sensed soil moisture. Hence methods to globally evaluate coarse-scale soil moisture estimates are required. The second study then compares two recently developed methods to globally estimate root mean square errors in soil moisture, again focusing on the ASCAT and AMSR-E near-surface soil moisture data sets.
Dr. Clara Draper has been a Research Associate at GMAO/GEST(AR) since early 2011. Her research is focused on improving the estimation of land surface states and fluxes in atmospheric models. Most recently she has been working on the development of land data assimilation for use in weather forecasting models. Dr. Draper received a BSc (Maths) / BEng (Environmental) with Honours from the University of Melbourne in 2001. She then worked for several years as a consulting engineer in Australia and Vietnam, before obtaining an MSc in Meteorology from Monash University in 2006, and a PhD from the Department of Civil and Environmental Engineering at the University of Melbourne in 2011. During her graduate studies Dr. Draper was working at the Australian Bureau of Meteorology Research Centre, where she diagnosed the atmospheric water cycle in the Bureau's weather forecasting systems, and developed a strategy to assimilate remotely sensed soil moisture into the their weather forecasting models. Before coming to GMAO Dr. Draper spent 2010 working for EUMETSAT / Meteo-France, testing the impact of assimilating near-surface soil moisture information on simulated surface water fluxes and stream flow forecasts.