In order to understand the rising number of flash floods and landslides in the densely populated region of southeastern Brazil, this study analyzes the spatial and temporal changes in precipitation from 1978 to 2014. We focus on the sensitivity of mountainous regions, specifically the Rio de Janeiro (RJMR) and Santa Catarina (SCMR) regions. Daily rainfall observations are aggregated into annual and seasonal indexes, and RClimdex is used to evaluate a suite of precipitation and extreme event indexes. Results show positive annual and seasonal precipitation trends during all seasons except for the winter season in the RJMR. Diverse change points in their time series, spatial differences in the trends at individual stations, and trends associated with elevation suggest that despite the close proximity of these two regions, climate impacts are not uniform across all of southeastern Brazil. The majority of precipitation-related indexes present positive trends, especially in the extreme precipitation indexes (PRCPTOT, RX1day, Rx5day and R30 mm). Statistically significant positive correlations are discovered between landslides/flash floods events and annual maximum 1-day and 5-day consecutive precipitation, and these indexes may be useful indicators of natural hazard events for this region.
Department of Agricultural Engineering, Universidade Federal de Viçosa, Viçosa, Brazil;Department of Agricultural Engineering, Universidade Federal de Viçosa, Viçosa, Brazil;Polar Meteorology Group, Byrd Polar and Climate Research Center, The Ohio State University, Columbus, OH, USA;Polar Meteorology Group, Byrd Polar and Climate Research Center, The Ohio State University, Columbus, OH, USA;Polar Meteorology Group, Byrd Polar and Climate Research Center, The Ohio State University, Columbus, OH, USA;Atmospheric Sciences Program, Department of Geography, The Ohio State University, Columbus, OH, USA;Universidade Federal Rural do Rio de Janeiro, Três Rios, Rio de Janeiro, Brazil
Recommended Citation:
Alvaro Ávila,Flavio Justino,Aaron Wilson,et al. Recent precipitation trends, flash floods and landslides in southern Brazil[J]. Environmental Research Letters,2016-01-01,11(11)