Climatic Normals in Chacras de Coria. Evolution of Air Temperature for the 1959-2020 Period

Abstract

Air temperature data registered from 1959 to 2020 by the Chacras de Coria meteorological station (32°59' S Lat.; 68°52' W Long.) were analyzed to characterize the site and identify trends considering the climate change scenario. We ensured quality and homogeneity of the time series following the procedures of the Standard World Meteorological Organization, calculating reference (1961-1990) and regulatory (1991-2020) climatological normals. The CLIMPACT package detected trends in temperature-related indices, including extreme values, daily thermal amplitude, and degree days. The results reveal that the 1991-2020 period was 0.6°C warmer than 1961-1990. Significant increases were observed in average minimum (0.12°C/decade) and average maximum (0.20°C/decade) temperatures. Extreme minimum and maximum temperatures also increased by 0.11°C/decade and 0.33°C/decade, respectively, resulting in fewer cold nights (-0.49%/decade) and more hot days (1.6%/decade). Daily temperature ranges increased by 0.11°C/decade, and degree days by 52 DD/decade. These findings are consistent with global warming evidence. A corrected and homogenized database spanning over 60 years is available for future climatological studies.

Highlights:

• A 62-year (1959–2020) homogenized and quality-controlled daily temperature database was established for Chacras de Coria using WMO standards and the CLIMPACT package.
• The regulatory climate normal period (1991–2020) was 0.6 °C warmer than the reference normal period (1961–1990).
• The Daily Thermal Range (DTR) increased by 0.11 °C per decade; maximum temperatures rose significantly faster (0.20 °C/decade) than minimum temperatures (0.12 °C/decade), an asymmetrical increase of 66.6%.
• Analysis of extreme indices reveals a decrease in cold nights (-0.49%/decade) and a significant rise in hot days (1.6%/decade).
• Annual Grow Degree Days (GDD) increased by 52 DD per decade, indicating higher energy availability that may shorten the cycles of ectothermic organisms.