Variations in the Isotopic Composition of Daily Precipitation in the Central Region of the State of São Paulo and its Relations with Moisture Transport

Abstract

The determination of the isotopic composition of water has become increasingly relevant in hydrometeorological studies, especially in those related to the rain-forming processes, mainly due to the importance that climate change has in the scientific community. Despite the several numbers of studies carried in tropical regions that are based on the isotopic composition of precipitation, several questions still remain unanswered, thus, Brazil has a great research potential due to its very unique climate. In addition, the country is a region of environmental catastrophes that need investigation. One of the reasons for this unique scenario are the climatic conditions that, together with different atmospheric systems, transpose the location of this research, carried out in the central region of the state of São Paulo. In this study, we intend to understand which points are the main climatic parameters responsible for the variation in the isotopic composition of precipitation between events. Therefore, data based on the isotopic composition of precipitation collected in the region presented will be analyzed. We will use events with precipitation volume greater than 15mm.day-1 of rain collected in the year 2021, based on data taken from the DEACGON meteorological station of the Center for Environmental Studies (same location where isotopic events were collected). For the synoptic analysis, Reanalysis data will be obtained together with information from Institutes, such as the National Center for Environmental Prediction (NCEP) and National Center for Atmospheric Research (NCAR). From the samples already collected and analyzed, daily precipitation events will be compiled and later the analysis of trajectories via the HYSPLIT model will be incorporated into the research, together with the creation of graphs for statistical analysis using the R programming software.