LINEAR TREND OF AIR TEMPERATURE VALUES FOR CITIES IN THE EASTERN PARANÁ STATE BETWEEN 1925 AND 2020

Abstract

The planet is undergoing a process of global warming caused by the emission of greenhouse gases and changes in land use and occupation. On the other hand, there is a question about whether the effects of global warming are already being felt on a local scale. To answer this question, the present research used daily data of maximum and minimum air temperatures for a historical series from 1925 to 2020, recorded in three cities in the eastern region of Paraná: Curitiba, Castro, and Paranaguá. The R software was used to process the RClimpact package, which generates climate change detection indices. It was found that there is statistical significance in the variation of the indices a) FD2, which showed a reduction in the number of days with temperatures below 2ºC; b) the SU30 index, indicating that the number of days with temperatures above 30ºC increased during the analyzed period; and c) the TR20 index, indicating an increase in the number of days with minimum temperatures above 20ºC. It is concluded that the warming recorded in Paraná is not due to short or recent series but is statistically significant even with long time series, such as those analyzed in this research. Thus, it is evident that the signs of global warming can be unmistakably felt on a local scale, which puts pressure on energy, agricultural, health, civil defense systems, and so on, in addition to altering atmospheric circulation, resulting in more extreme climatic events.