Seminar: Ardeshir Ebtehaj

Estimating Vegetation Optical Depth and Soil Permittivity over Snow-covered Boreal Forests and Permafrost using Satellite Data
April 17, 3:30 to 4:30pm

Soils 415 and Zoom


Permafrost soils and Arctic vegetation play an important role in the global carbon cycle. A review of recent advances in remote sensing of vegetation and permafrost dielectric properties using L-band microwave radiometry is presented. A new radiative transfer model is introduced that can account for microwave emission of the soil-snow-vegetation continuum through a closed-form solution of Maxwell's equations, considering the intervening dry snow layer as a loss-less medium. It is demonstrated that the model enables retrieval of vegetation optical depth (VOD) and ground permittivity from the L-band brightness temperatures by the Soil Moisture Active Passive (SMAP) satellite over the snow-covered Arctic landscape. In the absence of dense in situ observations, the retrievals are causally validated using auxiliary variables including ground temperature, above-ground biomass, tree height, and net ecosystem exchange of carbon dioxide. Time-series analyses promise using satellite data, we can expand our understanding of the land-atmosphere interactions and exchange of carbon fluxes over Arctic permafrost. 

Event Speaker
man with black hair and black shirt




Ardeshir Ebtehaj, Associate Professor in the Department of Civil, Environmental and Geo-Engineering