Climate change projections of boreal summer precipitation over tropical America by using statistical downscaling from CMIP5 models

Climate change projections for the last 30 years of the 21st century, for boreal summer precipitation in tropical America, have been made by developing a statistical downscaling (SD) model applied to the SLP outputs of 20 GCMs of CMIP5, for present climate (1970–2000), and for future (2071–2100) under the RCP2.6, RCP4.5 and RCP8.5 scenarios. For present climate, many SD GCMs faithfully reproduce the precipitation field in many regions of the study area. For future climate, as the radiative forcing increases, the projected changes intensify and the regions affected expand, with higher coherence between models. The zone between central and southeastern Brazil registered the most pronounced precipitation changes by a large number of SD models, even for the RCP2.6. Except for this region in Brazil, in general, the changes in rainfall range from moderate (± 25%) to intense (from ±70% to ±100%) as the radiative forcing increases from the RCP2.6−RCP8.5. For this latter scenario, all SD models present significant precipitation changes for more than 50% of the area, in some cases reaching 75% of area with significant changes. For the ensemble mean, the results show three extensive regions with significant changes under the three scenarios, the most highlighted changes being for the RCP8.5: a northwest-southeast band that extends from northern Mexico to eastern Brazil, crossing through northern Colombia, along with the regions in the south of the study area, with generally moderate precipitation increases; and a band that extends from eastern Ecuador to southeastern Brazil, with major decreasing changes. This pattern of change could be related with a possible strengthening in frequency in terms of La Niña events for the end of the century

Boreal · Climate change · Climate model · Climatology · Coupled model intercomparison project · Downscaling · Forcing (mathematics · Geography · Meteorology · Precipitation · Radiative forcing · Representative Concentration Pathways · Climate variability and models · Environmental Science · Meteorological Phenomena and Simulations · Plant Water Relations and Carbon Dynamics · Geology · Oceanography

• The next generation of scenarios for climate change research and assessment

  Open Access•Richard H Moss, Jae Edmonds et al.•Nature•2010

  Add to list

• The NCEP/NCAR 40-Year Reanalysis Project

  Eugenia Kalnay, Masao Kanamitsu et al.•Bulletin of the American…•1996

  Add to list

• Future changes in precipitation and impacts on extreme streamflow over Amazonian sub-basins

  Open Access•Matthieu Guimberteau, Josyane Ronchail et al.•Environmental Research Letters•2013

  Add to list