Temporal Variations in Tucson, Arizona Summertime Atmospheric Moisture, Temperature and Weather Stress Levels

Abstract

Summertime temperature, dewpoint, relative humidity, apparent temperature and weather stress levels have not changed significantly over the past 37 years at the Tucson, Arizona Municipal Airport. However, several of these variables show substantial trends during the most recent 18-year subperiod when the Tucson growth rate has been highest. The results for Tucson are quite different from the statistically significant changes in local climate reported for the Phoenix Airport during the same period of record. The differences in the changing weather conditions between these two desert cities appear to be related to (a) the smaller population in Tucson, (b) the position of the Tucson airport measurement site near the outskirts of the city as opposed to the centrally located airport in Phoenix and (c) the type of landscapes being replaced by these rapidly growing urban areas. The city of Phoenix is expanding generally into irrigated agricultural lands, while in Tucson, the bulk of the urban expansion is into the surrounding dryland areas. The results of this study are particularly useful in assessing the impact of urbanization on the local climate within a desert region.