Downwelling longwave radiation and sensible heat flux observations are critical for surface temperature and emissivity estimation from flux tower data.

ABSTRACT: Land surface temperature (LST) is a preeminent state variable that controls the energy and water exchange between the Earth's surface and the atmosphere. At the landscape-scale, LST is derived from thermal infrared radiance measured using space-borne radiometers. In contrast, plot-scale LST estimation at flux tower sites is commonly based on the inversion of upwelling longwave radiation captured by tower-mounted radiometers, whereas the role of the downwelling longwave radiation component is often ignored. We found that neglecting the reflected downwelling longwave radiation leads not only to substantial bias in plot-scale LST estimation, but also have important implications for the estimation of surface emissivity on which LST is co-dependent. The present study proposes a novel method for

SUBMITTER: Thakur G 

PROVIDER: S-EPMC9124221 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature