On the behavior of rainfall maxima at the eastern Andes

摘要: Abstract In this study, we detect high percentile rainfall events in the eastern central Andes, based on Tropical Rainfall Measuring Mission (TRMM) with a spatial resolution of 0.25 × 0.25°, temporal 3 h, and for duration from 2001 to 2018. We identify three areas mean accumulated analyze their atmospheric behaviour characteristics specific focus extreme events. Extreme are defined by above 95th daily rainfall. Austral summer (DJF) is period year presenting most frequent over these regions. Daily statistics show that maxima, as well associated events, produced during night. For considered period, ERA-Interim reanalysis data, provided European Centre Medium-Range Weather Forecasts (ECMWF) 0.75° x0.75° 6-hourly resolutions, were used analysis meso- synoptic-scale patterns. Night- day-time differences indicate nocturnal overload northerly northeasterly low-level humidity flows arriving tropical South America. Under conditions, cooling descending air mountains may find unstable at surface, giving place development strong local convection. Another possible mechanism presented here: forced ascent flow due mountains, disrupting stratification generating vertical displacement trajectories. A Principal Component Analysis (PCA) T-mode applied day- night-time data maximum The results correlation each subregion under study night-time, whereas no patterns found. This confirms observed behavior within hotspots.