Development of latitudinal land and sea temperature indices for climate monitoring

Global land and sea surface temperatures are used each month at the National Climatic Data Center to produce century-scale time series for use in near-real-time climate monitoring. However, these long-term aggregations of land and sea data are made only on a global scale. A more complete analysis of land and sea surface temperature changes requires the development of time series on scales other than global. Here we document a method for correlating modern satellite and in-situ surface temperature products with long-term in-situ-only surface air and sea surface temperatures to derive land and sea surface temperature time series within three latitude bands; 90° N - 20° N, 20° N - 20° S, and 20° S - 90° S. We also incorporate a blended satellite/in-situ land temperature data set to improve spatial coverage over areas with sparse in-situ coverage.