High resolution soil moisture parameterization of land surface models [funded by HGF-EDA] - Status: closed
Dr. Boris Thies
The high spatial resolution of the soil moisture product provided by Tandem-L will be used to regionalise a soil vegetation atmosphere transfer model for the study area in Southern Ecuador. The interactions between soil, vegetation and atmosphere including the seasonal variation in plant structure and function will be investigated by integrating the Tandem-L soil moisture data into the adapted land model. For this purpose the first step will consist in the development and implementation of a proper assimilation scheme for the level 3 soil moisture product. Since Tandem-L data will only be available after the launch of both satellites, data from ESA's Soil Moisture Ocean Salinity (SMOS) Earth Explorer mission (available since 2009) as well as from NASA's SMAP (Soil Moisture Active Passive) mission (scheduled launch 2014) will used for the development. Both systems provide a repetition rate of 1-2 days and operate in the L-band. Thus, they will be used as a substitute for the forthcoming Tandem-L data products. However, because of the much coarser resolution of the SMOS and SMAP soil moisture products a method has to be developed that allows to integrate the coarse-scale soil moisture data into the regional model scale (50m). The development of an appropriate downscaling method and the analysis of the model behaviour and simulation results for differing spatial scales will form the core of second workign package. By the same time the model sensitivity on the accuracy of the provided soil moisture product (5-10%) will be investigated. By this means the propagation of soil moisture retrieval uncertainty in the simulation of energy fluxes, gas exchange and vegetation growth will be investigated for varying spatial resolution. For the last working package the potential improvement gained by more accurate soil moisture information with higher spatial and temporal resolution will be assessed. To this end, the model performance will be extensively evaluated on varying spatial scales using field measurements of the energy fluxes, gas exchange, leaf area index and biomass in the study area.