Analysis of the climate change signal in Mexico City given disagreeing data sources and scattered projections

Abstract

Study region: This study investigates the annual and seasonal trends in precipitation and temperature at meteorological stations in Mexico City, and compares them with gridded datasets and projections from General Circulation Models. Study Focus: The outputs of climatic trend analysis are highly sensitive to the quality and continuity of data, as well as natural variability effects including low frequency persistence. This study evaluates the changes in average annual precipitation and temperature from approximately 1950–2013, and projected changes for 2036–2065. New hydrological insights for the region: Results shows statistically significant increasing trends in the winter mean temperature and the summer precipitation by average rates of 0.1 °C/decade and 17.8 mm/decade, respectively. Within the next 30 years, temperature is projected to continue to increase between 1℃ to 3℃ with an unclear signal in precipitation change, but possibly an increase in late-season monsoon rainfall. Keywords: Temperature, Precipitation, Trend analysis, Mann-Kendall test, Sen's slope estimator, Mexico City