The CHIRTmax dataset is based on time-varying 0.05 degree satellite thermal infrared-based estimates of monthly Tmax anomalies combined with a static high resolution (0.05) background Tmax climatology describing average 1981-2010 air temperature conditions at each location. For the infrared-based Tmax anomalies, in each grid cell, if at least 10-daily non-cloudy CHIRTmax estimates were available, a monthly CHIRTmax was calculated from the average of these values. The 1983–2016 time period was then used to calculate monthly CHIRTmax climatologies (mean fields) and standard deviations. These values were used to translate the monthly varying CHIRTmax values into standardized anomalies (Z-scores). Anomaly fields were then estimated and translated into estimates of 2-m maximum air temperatures. For each month, this translation was achieved by multiplying CHIRTmax Z-scores by the local 1983–2016 standard deviation of the gridded CRU Tmax product. These monthly standardized deviations were calculated at the native CRU resolution (0.5) and then resampled to a 0.05 resolution. For details, please see Funk et al. 2019.