HR: 1340h
AN: H23E-1168    [Abstracts]
TI: Air-to-Soil Transition Model
AU: * Schwank, M
EM: mike.schwank@env.ethz.ch
AF: ETH-Zrich, Institute of terrestrial ecolocy, Grabenstrasse 11a, Schlieren, 8952 Switzerland
AU: Schneeberger, K
EM: katrin.schneeberger@ubs.ch
AF: ETH-Zrich, Institute of terrestrial ecolocy, Grabenstrasse 11a, Schlieren, 8952 Switzerland
AU: M„tzler, C
EM: matzler@iap.unibe.ch
AF: University Bern,, Sidlerstrasse 5, Bern, 3012 Switzerland
AU: Flhler, H
EM: fluehler@env.ethz.ch
AF: ETH-Zrich, Institute of terrestrial ecolocy, Grabenstrasse 11a, Schlieren, 8952 Switzerland
AB: Within the last three years, a 1.4 GHz radiometer has been applied for bare soil experiments. The radiometer observations were compared with simultaneously measured soil water content and temperature. The remotely sensed and in-situ measured data were synchronous and therefore suitable to test radiative transfer models by comparing predicted and measured data. The soil reflectivities derived from the radiometer and from the ground truth data were inconsistent when using the Fresnel formula. To examine possible reasons for the observed discrepancy, other physically based surface reflectivity models were tested, but none of them was able to explain the observations. Hence, we propose a new roughness model denoted as air-to-soil transition model. It describes the influence of the topsoil structure on the L-band radiation as an impedance matching between the dielectric constants of the topsoil and air using an effective dielectric profile to describe the transition from air to soil. The new model is capable to explain the observations.
DE: 1866 Soil moisture
DE: 0933 Remote sensing
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting