Toward High-Resolution Soil Moisture Monitoring over India by Combining
Remote Sensing Products with Land Surface Models
Abstract
Soil moisture is a vital climatic variable driving environmental and
biological processes. Large scale soil moisture can be estimated using
Land Surface Models or observed using active and passive microwave
remote sensing. Increasing availability of remotely sensed soil moisture
retrievals has allowed for constraining Land Surface Model (LSM)
estimates. Though the accuracy of remote sensing datasets is constrained
by soil roughness, vegetation, and surface temperature, combining them
with LSMs allow us to reduce errors in soil moisture estimates. This
study assimilates the SMOPs-ASCAT, ESA-CCI and SMAP soil moisture
retrievals into a land surface model u sing an ensemble Kalman filter.
The open-loop and data assimilated soil moisture outputs are evaluated
against the ground-based sensor data. This demonstrates the
establishment of an Indian Land Data Assimilation System (ILDAS) with
the goal of providing accurate soil moisture products at high spatial
and temporal resolution over India.