Estimation of surface temperature variations due to changes in sky and solar flux with elevation

S. Hummer-Miller

doi:10.1029/gl008i006p00595

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Estimation of surface temperature variations due to changes in sky and solar flux with elevation

S. Hummer-Miller

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Abstract

Sky and solar radiance are of major importance in determining the ground temperature. Knowledge of their behavior is a fundamental part of surface temperature models. These two fluxes vary with elevation and this variation produces temperature changes. Therefore, when using thermal-property differences to discriminate geologic materials, these flux variations with elevation need to be considered. From a representative set of field observations, it was found that flux variations with elevation can cause changes in the mean diurnal temperature gradient from −4° to −14°C per km evaluated at 2000 m. Changes in the temperature-difference gradient of 1°-2°C per km are also produced which is equivalent to an effective thermal-inertia gradient of 100 W s 1/2 m −2 K −1 per km. Thus, exposed bedrock on topographic ridges will appear to have a lower thermal inertia due to the additional effect.

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S. Hummer-Miller. 2012-12-07. Estimation of surface temperature variations due to changes in sky and solar flux with elevation. https://doi.org/10.1029/gl008i006p00595

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