Measuring temperature profile using multi-frequency microwave radiometric observation-theoretical modeling

Abstract

In this theoretical paper, we propose method for the measurement of temperature profile in the topsoil of Arctic tundra using observations of brightness temperature at frequencies of 1.4, 6.93, 7.3 and 10.7 GHz. A multi-frequency physical model of microwave emission of bare soil and dielectric model of Arctic tundra soil, with temperature profiles, which were measured in the active topsoil with using Toolik climate station on the North Slope of Alaska, were used to calculate “measured” values of brightness temperature. In the approximation of piecewise linear profile of soil temperature, from the “measured” values of brightness temperature were retrieved temperature profiles and were compared with ones, which were measured at the Toolik station from 2010 to 2011. The retrieved values of soil temperatures at the depth of 0.6cm and 16.0cm deviated from measured ones by 1.3°C and 3.2°C in terms of root-mean-square error, and by 0.92 and 0.62 in terms of determination coefficient, respectively.