Evidence of the variation in the rate of change of temperature and precipitation

One of the most pressing challenges currently is climate change, and to face it, it is desirable to have the most detailed information possible on the distribution of climate metrics and the covariates that alter their fluctuations. This study investigated the spatial variations of the temperature and precipitation variables more sensitive to the unit change in elevation above sea level, considering the relative effects of latitude and solar radiation as covariates. For this, the analysis of covariance was applied to analyze data from 32,111 sampling units, systematically distributed in mainland Mexico, hypothesizing a constant and uniform rate of change of climate variables as the values of elevation above sea level increase and a non-significant effect of the covariates on the elevation-climate relationships. The results show that the rate of change of the studied variables varies at different latitudinal and altitudinal gradients. For example, without considering any covariate, for each meter that the elevation increases, the mean annual temperature decreases on average by 0.00473 °C, the mean temperature of the driest quarter decreases by 0.00488 °C, and the mean temperature of the warmest quarter decreases by 0.00449 °C. This means that for every kilometer of elevation, these variables decrease by 4.73, 4.88, and 4.49 °C, respectively. Yet, when the data were stratified by covariates, these values, as well as the rates of change in precipitation, varied significantly. There were also signs of a stronger correlation between altitude and precipitation for the driest month and driest quarter of over 30°N than in latitudes nearer to the equator.