Validating the topographic climatology logic of the MTCLIM model

The topographic climatology logic of the MTCLIM model was validated using a comparison of modeled air temperatures vs. remotely sensed, thermal infrared (TIR) surface temperatures from three Daedalus Thematic Mapper Simulator scenes. The TIR data was taken in 1990 near Sisters, Oregon, as part of the NASA OTTER project. The original air temperature calculation method was modified for the spatial context of this study. After stratifying by canopy closure and relative solar loading, r{sup 2} values of 0.74, 0.89, and 0.97 were obtained for the March, June, and August scenes, respectively, using a modified air temperature algorithm. Consistently lower coefficients of determination were obtained using the original air temperature algorithm on the same data r{sup 2} values of .070, .52, and .66 for the March, June, and August samples respectively. The difficulties of comparing screen height air temperatures with remotely sensed surface temperatures are discussed, and several ideas for follow-on studies are suggested.