TITLE:
Dynamical Donwscaling for Railroad Areas in Eastern Amazon and Southeastern Brazil: Current Climate and Near-Future Projections
AUTHORS:
Everaldo B. De Souza, Bergson C. de Moraes, Douglas B. S. Ferreira, Luiz Gylvan Meira Filho
KEYWORDS:
Regional Climate Modeling; Rainy and Dry Seasons; Climate Change; Brazil Climate; REGCM4
JOURNAL NAME:
Atmospheric and Climate Sciences,
Vol.4 No.2,
April
2,
2014
ABSTRACT:
We performed a dynamic
downscaling using REGCM4 regional model driven by MPI global model for current
(1990/2012) and near-future (2015/2039) climate in order to characterize the seasonal
rainfall regimes throughout the railroad areas in eastern Amazon and
southeastern Brazil. The analysis of observational data for the current climate
indicated the existence of pronounced spatial variations in rainfall regime
across railroad regions during both the rainy and dry seasons. Although models
have presented generalized underestimation, the regional model showed improvements
on spatial representation and intensity of the rainfall in comparison with
global model results. We reported the future projections taking into account
the correction of simulated rainfall by the values of the biases found in each
respective seasonal regime, so that the results are expressed by percentage
changes of the future (2015/2037) relative to the current climate patterns. For
the railroad in eastern Amazon, projections indicate a weak decrease of
rainfall of about -15% in the rainy season (January to May), however during the
dry season (June to October) are expected drastic reductions between -70% and
-90% in south (Carajás in Pará state) and north (Sao Luis in Maranhao state)
portions. Conversely, for the railroad in southeast Brazil, model projections
point out for an increased rainfall regime during the rainy season (October to
February) around +30% to +40% in the east part of the region over the Espírito
Santo state.