Satellite-Based Adjustments for the Urban Heat Island Temperature Bias

TLDR

Satellite-derived data could enable a globally consistent method for analyzing the urban heat island bias. The study compared urban–rural temperature differences from surface stations to satellite-derived NDVI and surface radiant temperature, developing relationships during 1989–91 and validating them with 1992–93 data. Urban–rural temperature differences were linearly linked to NDVI and Tsfc differences, but only less than 40 % of UHI bias variation was explained by these variables, and satellite-based UHI bias estimates had error levels comparable to population-based estimates.

Abstract

Monthly and seasonal relationships between urban–rural differences in minimum, maximum, and average temperatures measured at surface-based observation stations were compared to satellite-derived Advanced Very High Resolution Radiometer estimates of a normalized difference vegetation index (NDVI) and surface radiant temperature (Tsfc). The relationships between surface- and satellite-derived variables were developed during 1989–91 and tested on data acquired during 1992–93. The urban–rural differences in air temperature were linearly related to urban–rural differences in the NDVI and Tsfc. A statistically significant but relatively small (less than 40%) amount of the variation in these urban–rural differences in air temperature [the urban heat island (UHI) bias] was associated with variation in the urban–rural differences in NDVI and Tsfc. A comparison of the satellite-based estimates of the UHI bias with population-based estimates of the UHI bias indicated similar levels of error. The use of satellite-derived data may contribute to a globally consistent method for analysis of the urban heat island bias.