@Article{ShongweOlHuBoCoAa:2009:SoAf,
author = "Shongwe, M. E. and Oldenborgh, Geert Jan van and Hurk, B. J. J. M.
van den and Boer, B. de and Coelho, Caio Augusto dos Santos and
Aalst, M. K. van",
affiliation = "{} and Royal Netherlands Meteorological Institute, De Bilt,
Netherlands and {} and {} and {Instituto Nacional de Pesquisas
Espaciais (INPE)}",
title = "Projected changes in mean and extreme precipitation in Africa
under global warming. Part I: Southern Africa",
journal = "Journal of Climate",
year = "2009",
volume = "22",
number = "13",
pages = "3819--3837",
month = "July",
abstract = "This study investigates likely changes in mean and extreme
precipitation over southern Africa in response to changes in
radiative forcing using an ensemble of global climate models
prepared for the Intergovernmental Panel on Climate Change (IPCC)
Fourth Assessment Report (AR4). Extreme seasonal precipitation is
defined in terms of 10-yr return levels obtained by inverting a
generalized Pareto distribution fitted to excesses above a
predefined high threshold. Both present (control) and future
climate precipitation extremes are estimated. The
future-to-control climate ratio of 10-yr return levels is then
used as an indicator for the likely changes in extreme seasonal
precipitation. A Bayesian approach to multimodel ensembling is
adopted. The relative weights assigned to each of the model
simulations is determined from bias, convergence, and correlation.
Using this method, the probable limits of the changes in mean and
extreme precipitation are estimated from their posterior
distribution. Over the western parts of southern Africa, an
increase in the severity of dry extremes parallels a statistically
significant decrease in mean precipitation during austral summer
months. A notable delay in the onset of the rainy season is found
in almost the entire region. An early cessation is found in many
parts. This implies a statistically significant shortening of the
rainy season. A substantial reduction in moisture influx from the
southwestern Indian Ocean during austral spring is projected. This
and the preaustral spring moisture deficits are possible
mechanisms delaying the rainfall onset in southern Africa. A
possible offshore (northeasterly) shift of the tropical-temperate
cloud band is consistent with more severe droughts in the
southwest of southern Africa and enhanced precipitation farther
north in Zambia, Malawi, and northern Mozambique. This study shows
that changes in the mean vary on relatively small spatial scales
in southern Africa and differ between seasons. Changes in extremes
often, but not always, parallel changes in the mean
precipitation.",
doi = "10.1175/2009JCLI2317.1",
url = "http://dx.doi.org/10.1175/2009JCLI2317.1",
issn = "0894-8755",
label = "lattes: 4978912302419377 5 ShongweOldHurBoeCoe:2009:SoAf",
language = "en",
targetfile = "Coelho_projected.pdf",
urlaccessdate = "20 maio 2024"
}