Ferreira, N.C.R.; Chou, S.C.; Dereczynski, C. Evaluation of Subseasonal Precipitation Simulations for the Sao Francisco River Basin, Brazil. Climate2023, 11, 213.
Ferreira, N.C.R.; Chou, S.C.; Dereczynski, C. Evaluation of Subseasonal Precipitation Simulations for the Sao Francisco River Basin, Brazil. Climate 2023, 11, 213.
Ferreira, N.C.R.; Chou, S.C.; Dereczynski, C. Evaluation of Subseasonal Precipitation Simulations for the Sao Francisco River Basin, Brazil. Climate2023, 11, 213.
Ferreira, N.C.R.; Chou, S.C.; Dereczynski, C. Evaluation of Subseasonal Precipitation Simulations for the Sao Francisco River Basin, Brazil. Climate 2023, 11, 213.
Abstract
Water conflicts have been a significant issue in Brazil, especially in the Sao Francisco River basin. Subseasonal forecasts, up to a 60-day forecast range, can provide information to support decision-makers in managing water resources in the river basin, especially before drought events. Predictability in the subseasonal forecasts range is a research topic as this range contains mixed dependence on weather and seasonal phenomena. Numerical models may inherit this mixed dependence on their skills. The objective of this paper is to evaluate the Eta Model simulations to reproduce the drought events between the years 2011 and 2016. Two sets of 60-day simulations were produced; one started in September (SO) and the other in January (JF) each year. These months were chosen to evaluate the model skill to reproduce the onset and the middle of the rainy seasons in Central Brazil, where the Upper Sao Francisco River is located. The SO simulations reproduced the observed spatial distribution of precipitation but underestimated the amounts. Precipitation errors exhibit large variability across the subbasins. The JF simulations also reproduced the observed precipitation distribution but overestimated it in the Upper and Lower subbasins. The JF simulations better captured the interannual variability of precipitation. The 60-day simulations were discretized in six 10-day accumulations to assess the intra-monthly variability. They showed that simulations can capture the onset of the rainy season and the small amounts of the rainy months that occurred in these severe drought years.
Keywords
Climate extremes; transition season; rainy season; model errors; extended range
Subject
Environmental and Earth Sciences, Atmospheric Science and Meteorology
Copyright:
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