Characterization of Synoptic Systems Triggering Disasters in the State of Espírito Santo, Brazil

Abstract

Despite the large amount of research about hydrometeorological disasters in southern Brazil, only a tiny part covers the State of Espírito Santo. The State is frequently affected by disasters of this nature. Therefore, this work aims to determine and characterize the types of synoptic systems that produce heavy rainfall and cause disasters in ES. Between 2013 and 2021, the S2ID database, synoptic charts from CPTEC, images from GOES 13 and 16 satellites, and precipitation data from INMET were used to select the dates and characterize the meteorological situation. Additionally, the ERA5 reanalysis was used for the construction of composite. It was found that disasters that affect ES occur mainly during the summer, which agrees with a thermodynamically more unstable atmosphere. The main systems identified can be described as follows: 1- Intense Frontal Systems related to blocking configuration in previous days that allow humid air advection from the Atlantic Ocean, through the presence of an anticyclone together with colder air at medium levels; 2- SACZ related to a warm anomalous anticyclone in the Atlantic and an intense low-pressure center located to the north, also showing a blocking pattern; 3- Troughs with slow displacement and low baroclinicity associated with high convective instability, acting as an extension of the Chaco Low and Thermo-Orographic Low, and 4- Cold core Cyclones with barotropic characteristics, located over ES, linked to warm blocking anticyclones, positioned south of about 40–45°S. In general, these patterns could be identified at least 48 hours in advance, observing disturbances at higher latitudes.