Spatial variation of climate change indices in the state of Chiapas, Mexico

Abstract

Although climate change is evidenced by a steady increase in global temperature, several indicators have been defined and are represented by mathematical expressions called indices, which are identified, recorded, and compared to demonstrate variations in climate change. However, using these indices requires: (1) timely evaluation, and (2) determining their spatial variation over a given region. However, there are only a few studies on the spatial trend of these indices, which is important considering that the impacts of climate change, as well as the factors that determine them, are not spatially homogeneous. Therefore, information from the historical series (1969-2009) of 16 meteorological stations, distributed in Chiapas, Mexico, was used. To determine the spatial variation of the climatic indices, each index was associated with 25 environmental variables through multiple linear regressions defined by the stepwise procedure. According to the results, the environmental variables with the greatest significant influence (p < 0.001) were mean annual temperature, mean annual runoff, real evapotranspiration, mean minimum temperature, and mean annual isotherms. On the other hand, the variables not used in the models were: highest insolation in May, soil moisture regimes, hydrogeology, biotic provinces, and physiographic provinces. The results of multiple linear regression models defined high R² values (from 0.72 to 0.97), and the resulting mapping shows that each index defined a particular spatial variation. We conclude that, for the purpose of evidencing climate change, the process followed in this work can be used to determine the variation of this type of index in other regions.