Open water, inundated vegetation and upland vegetation discriminated through a disturbing atmosphere

Abstract. Methane is an important greenhouse gas. The areal extent of Boreal wetlands, source areas for methane, is poorly known. At times estimates have differed by as much as seven fold, which contributes uncertainty to present day energy and carbon budgets and to projections of future climates.

In this research we applied optical remote sensing technology to identify methane source areas in POLDER imagery collected from both aircraft and satellite. Our approach takes advantage of the specular reflecting properties of surface waters in order to differentiate inundated wetlands (with emergent vegetation), open water (without emergent vegetation) and non-inundated cover types.

Unlike our previous research, here we account for the affects of the disturbing atmosphere, presenting a radiative transfer model that represents an atmosphere above a mixed pixel that includes various proportions of open water, inundated vegetation and upland vegetation. The results show that our algorithm accurately identified these three cover types in both aircraft and satellite data. The results point to the probable importance of atmospheric correction to the discrimination procedure.