@InProceedings{ValverdeMare:2011:RaExEv,
author = "Valverde, Maria Cle{\'o}fe and Marengo, Jos{\'e} Antonio",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)}",
title = "Rainfall extremes events climatology over the Amazon basin",
year = "2011",
organization = "Proceedings of the Global Conference on Global Warming 2011.",
keywords = "Amazon basin, climatic extremes, heavy rainfall and regional
model.",
abstract = "The purpose of this study is to elaborate the climatology of
extremes indices of rainfall in the Amazon basin. For this
purpose, climatic indices (CDD, R95p, RX1day, Rnnmm) recommended
by the joint World Meteorological Organization CCL/CLIVAR/JCOMM
Expert Team on Climate Change Detection and Indices (ETCCDI) were
calculated. One of the most important aspects of this study is to
characterize possible change in extreme of rainfall (e.g. floods,
drought, etc) over Amazon basin, since these events have strongest
impacts on society. Extremes indices were derived from daily
precipitation at NOAALs Climate Prediction Center (CPCp) with
resolution 1x1, for period 1979-2005. The indices calculated in
this study are R50mm and R80mm defined as the number of days per
year with precipitation amount . 50 mm and . 80mm respectively.
CDD defined as annual maximum number of consecutive dry days and
R95p (very wet days exceeding the 95th percentile).These indices
can be related to drought (CDD) and floods (R95p) events. The
rainfall of Amazon basin exhibits high interannual and
interdecadal variability associated with ENSO events and with the
positive anomaly of SST in the North Atlantic. The annual
variability of extreme precipitation indices, such as, maximum
length of dry spells (CDD) and RR> 95p (R95p) were sensitive to
identification periods of droughts. Also, it verified that extreme
rains . 50mm and . 80 mm (R50mm and R80mm), occur with or without
events El Nino. On the other hand, droughts are not necessarily
associated with a diminution of extreme rainfall events (R50mm e
R80mm). Individual locations in the west of the basin (Santarem,
Cachimbo and Manaus stations) show negative trends of CDD.
However, Rio Branco station (southeast of basin) showed
statistically significant positive trends of CDD, and captured the
drought of 2005 and 2010. The future scenarios of ETA_HadCM3 model
for the period 2011-2040, show an increase (decrease) of the index
CDD (R95p) for the average area of the Amazon basin, and it will
be stronger in the 2071-2099 climatology. However, as this result
is a projection of model there are still many uncertainties. The
fact is that historically these extremes of rain are part of
climate variability in the region, and they can happen again.",
conference-location = "Lisbon, Portugal",
conference-year = "11-14, July",
targetfile = "MariaValverde_Rainfall.pdf",
urlaccessdate = "05 jun. 2024"
}