L-Band Disaggregation with C-Band Demonstration using SMAP and AMSR2 Data for Application to Forthcoming CIMR Measurements

Passive microwave remote sensing is used for mapping soil moisture globally. The upcoming European Copernicus Program’s Conical Imaging Microwave Radiometer (CIMR) mission can operate at five spectral bands, providing observations for understanding earth science at multiple spatial resolutions. This study explores the potential of enhancing spatial resolution by exploiting the overlap of band footprints. We aim to investigate whether spatial information from multi-resolution C-band at finer resolutions can be used to disaggregate L-band at coarser resolutions using existing brightness temperature (TB) data from SMAP and AMSR2 missions. We evaluate global performance between disaggregated TB and true TB retrievals and find improvements globally, especially near water bodies and with increasing heterogeniety. Results support the conclusion that C-band captures useful information for L-band disaggregation, demonstrating a potential to improve the spatial resolution of soil moisture products at L-band within the context of CIMR.