Moisture Roughness map in arctic national wildlife Refuge/Alaska

摘要

We propose an algorithm to estimate moisture level of active layer of permafrost over permafrost area. This algorithm is based on Oh's semi-empirical model, and PALSAR data observed both in winter and summer seasons with vh polarization. PALSAR vh polarization data observed in winter is used to estimate surface roughness of permafrost. Then, the estimated surface roughness and PALSAR vh polarization data observed in summer is used to estimate the moisture level of the active layer of the permafrost. The moisture levels estimated from PALSAR data moderately matched to those of validation data taken in the field with correction factor of 0.6, while the surface roughness value shows some difference. The possible cause of the difference observed in the roughness value is that the surface roughness derived from the field data collection represents the roughness of the top of the sphagnum moss layer covered on the active layer of the permafrost, while the one estimated from PALSAR represents the roughness of the underlying active layer of the permafrost.