Projected Changes in Mean and Extreme Precipitation in Africa under Global Warming. Part I: Southern Africa

AbstractProbable changes in mean and extreme precipitation in East Africa are estimated from general circulation models (GCMs) prepared for the Intergovernmental Panel on Climate Change Fourth Assessment Report (AR4). Bayesian statistics are used to derive the relative weights assigned to each member in the multimodel ensemble. There is substantial evidence in support of a positive shift of the whole rainfall distribution in East Africa during the wet seasons. The models give indications for an increase in mean precipitation rates and intensity of high rainfall events but for less severe droughts. Upward precipitation trends are projected from early this (twenty first) century. As in the observations, a statistically significant link between sea surface temperature gradients in the tropical Indian Ocean and short rains (October–December) in East Africa is simulated in the GCMs. Furthermore, most models project a differential warming of the Indian Ocean during boreal autumn. This is favorable for an increa...

[1]  B. Hewitson,et al.  Consensus between GCM climate change projections with empirical downscaling: precipitation downscaling over South Africa , 2006 .

[2]  B. Hewitson,et al.  Sensitivity of southern African climate to soil-moisture * , 2003 .

[3]  Peter J. Webster,et al.  Coupled ocean–atmosphere dynamics in the Indian Ocean during 1997–98 , 1999, Nature.

[4]  Thomas C. Peterson,et al.  Initial selection of a GCOS surface network , 1997 .

[5]  Tsing‐Chang Chen.  Maintenance of the Midtropospheric North African Summer Circulation: Saharan High and African Easterly Jet , 2005 .

[6]  Richard P. Allan,et al.  Water vapor variability in the tropics and its links to dynamics and precipitation , 2005 .

[7]  F. Semazzi,et al.  ENSO signals in East African rainfall seasons , 2000 .

[8]  R. Washington,et al.  Circulation anomalies associated with tropical-temperate troughs in southern Africa and the south west Indian Ocean , 1999 .

[9]  Kevin E. Trenberth,et al.  Trends and variability in column-integrated atmospheric water vapor , 2005 .

[10]  S. Coles,et al.  An Introduction to Statistical Modeling of Extreme Values , 2001 .

[11]  F. Zwiers,et al.  Changes in the Extremes in an Ensemble of Transient Climate Simulations with a Coupled Atmosphere–Ocean GCM , 2000 .

[12]  Richard A. Johnson,et al.  Applied Multivariate Statistical Analysis , 1983 .

[13]  C. Reason,et al.  Dry summers over northeastern South Africa and associated circulation anomalies , 2003 .

[14]  C. Reason,et al.  Dry spell frequencies and their variability over southern Africa , 2004 .

[15]  R. Saravanan,et al.  Oceanic Forcing of Sahel Rainfall on Interannual to Interdecadal Time Scales , 2003, Science.

[16]  C. Reason,et al.  Relationships between South African rainfall and SST anomalies in the Southwest Indian Ocean , 1999 .

[17]  M. Latif,et al.  The impact of decadal‐scale Indian Ocean sea surface temperature anomalies on Sahelian rainfall and the North Atlantic Oscillation , 2003 .

[18]  H. Douville,et al.  Influence of Soil Moisture on the Asian and African Monsoons. Part II: Interannual Variability. , 2002 .

[19]  S. Hastenrath,et al.  Diagnosing the 2005 Drought in Equatorial East Africa , 2007 .

[20]  S. Mason,et al.  SIMULATED CHANGES IN EXTREME RAINFALL OVER SOUTHERN AFRICA , 1997 .

[21]  A. Sterl,et al.  The ERA‐40 re‐analysis , 2005 .

[22]  M. Ward,et al.  Towards the prediction of the East Africa short rains based on sea‐surface temperature–atmosphere coupling , 1998 .

[23]  G. J. van Oldenborgh,et al.  Large-scale atmospheric circulation biases and changes in global climate model simulations and their importance for climate change in Central Europe , 2006 .

[24]  Ruth M. Doherty,et al.  African climate change: 1900-2100 , 2001 .

[25]  Gillian M. Mimmack,et al.  Changes in Extreme Rainfall Events in South Africa , 1999 .

[26]  Ngar-Cheung Lau,et al.  Remote Sea Surface Temperature Variations during ENSO: Evidence for a Tropical Atmospheric Bridge , 1999 .

[27]  K. Trenberth,et al.  The changing character of precipitation , 2003 .

[28]  W. Landman,et al.  Performance of recalibration systems for GCM forecasts for southern Africa , 2006 .

[29]  M. Collins,et al.  El Niño in a changing climate: a multi-model study , 2005 .

[30]  C. Reason.  Tropical cyclone Dera, the unusual 2000/01 tropical cyclone season in the South West Indian Ocean and associated rainfall anomalies over Southern Africa , 2007 .

[31]  M. Saier,et al.  Climate Change, 2007 , 2007 .

[32]  B. Hewitson,et al.  The Interannual Variability of the Onset of the Maize Growing Season over South Africa and Zimbabwe , 2005 .

[33]  I. Simmonds,et al.  Interannual variability of south-eastern African summer rainfall. Part II. Modelling the impact of sea-surface temperatures on rainfall and circulation , 1997 .

[34]  A. Hense,et al.  Internal variability in a 1000-yr control simulation with the coupled climate model ECHO-G — I. Near-surface temperature, precipitation and mean sea level pressure , 2005 .

[35]  F. Chauvin,et al.  Influence of Soil Moisture on the Asian and African Monsoons. Part I: Mean Monsoon and Daily Precipitation , 2001 .

[36]  D. Stephenson,et al.  Future extreme events in European climate: an exploration of regional climate model projections , 2007 .

[37]  Peter J. Webster,et al.  Interdecadal variability of the relationship between the Indian Ocean zonal mode and East African coastal rainfall anomalies , 2003 .

[38]  C. Reason,et al.  Ocean–Atmosphere Interaction in the Agulhas Current Region and a South African Extreme Weather Event , 2002 .

[39]  Raquel V. Francisco,et al.  Uncertainties in regional climate change prediction: a regional analysis of ensemble simulations with the HADCM2 coupled AOGCM , 2000 .

[40]  K. Cook.  The South Indian Convergence Zone and Interannual Rainfall Variability over Southern Africa , 2000 .

[41]  Anne Moorhead,et al.  Climate risk management in Africa : learning from practice , 2007 .

[42]  P. Tyson,et al.  Secular changes in South African rainfall: 1880 to 1972 , 1975 .

[43]  J. Houghton,et al.  Climate change 2001 : the scientific basis , 2001 .

[44]  P. Palmer,et al.  Water vapour transport associated with tropical–temperate trough systems over southern Africa and the southwest Indian Ocean , 2004 .

[45]  F. Zwiers,et al.  Changes in the Extremes of the Climate Simulated by CCC GCM2 under CO2 Doubling , 1998 .

[46]  R. Washington,et al.  Extreme wet years over southern Africa: Role of Indian Ocean sea surface temperatures , 2006 .

[47]  Swadhin K. Behera,et al.  Subtropical SST dipole events in the southern Indian Ocean , 2001 .

[48]  Richard L. Smith,et al.  Quantifying Uncertainty in Projections of Regional Climate Change: A Bayesian Approach to the Analysis of Multimodel Ensembles , 2005 .

[49]  F. Semazzi,et al.  Variability of East African rainfall based on multiyear Regcm3 simulations , 2007 .

[50]  B. Soden,et al.  Robust Responses of the Hydrological Cycle to Global Warming , 2006 .

[51]  G. Hegerl,et al.  Detection of human influence on twentieth-century precipitation trends , 2007, Nature.

[52]  C. Reason,et al.  Interannual variability in rainy season characteristics over the Limpopo region of southern Africa , 2005 .

[53]  B. Cook,et al.  Soil Moisture Feedbacks to Precipitation in Southern Africa , 2006 .

[54]  S. Klein,et al.  GFDL's CM2 Global Coupled Climate Models. Part I: Formulation and Simulation Characteristics , 2006 .

[55]  Ian Simmonds,et al.  INTERANNUAL VARIABILITY OF SOUTH‐EASTERN AFRICAN SUMMER RAINFALL. PART 1: RELATIONSHIPS WITH AIR–SEA INTERACTION PROCESSES , 1997 .

[56]  Claudia Tebaldi,et al.  Understanding future patterns of increased precipitation intensity in climate model simulations , 2005 .

[57]  D. Easterling,et al.  Trends in Intense Precipitation in the Climate Record , 2005 .

[58]  Francis W. Zwiers,et al.  Climate Change Detection and Attribution: Beyond Mean Temperature Signals , 2006 .

[59]  Corinne Le Quéré,et al.  Climate Change 2013: The Physical Science Basis , 2013 .

[60]  Gillian M. Mimmack,et al.  Choice of Distance Matrices in Cluster Analysis: Defining Regions , 2001 .

[61]  M. Ward,et al.  East African Rainfall and the Tropical Circulation/Convection on Intraseasonal to Interannual Timescales , 2000 .

[62]  H. V. D. Dool,et al.  Empirical Methods in Short-Term Climate Prediction , 2006 .

[63]  Paul Steele,et al.  Poverty and Climate Change Reducing the Vulnerability of the Poor through Adaptation , 2003 .

[64]  Kevin E. Trenberth,et al.  Atmospheric moisture recycling : Role of advection and local evaporation , 1999 .

[65]  F. Giorgi,et al.  Probability of regional climate change based on the Reliability Ensemble Averaging (REA) method , 2003 .

[66]  Richard Washington,et al.  Tropical-temperate links in southern african and southwest Indian Ocean satellite-derived daily rainfall , 1999 .

[67]  B. Goswami,et al.  A dipole mode in the tropical Indian Ocean , 1999, Nature.

[68]  M. Alexander,et al.  Remote Response of the Indian Ocean to Interannual SST Variations in the Tropical Pacific , 2004 .

[69]  F. Giorgi,et al.  Calculation of average, uncertainty range, and reliability of regional climate changes from AOGCM simulations via the reliability ensemble averaging (REA) method , 2002 .

[70]  Zong-ci Zhao,et al.  Climate change 2001, the scientific basis, chap. 8: model evaluation. Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel on Climate Change IPCC , 2001 .

[71]  John F. B. Mitchell,et al.  The simulation of SST, sea ice extents and ocean heat transports in a version of the Hadley Centre coupled model without flux adjustments , 2000 .

[72]  K. Cook.  A Southern Hemisphere Wave Response to ENSO with Implications for Southern Africa Precipitation , 2001 .

[73]  G. Hegerl,et al.  Changes in temperature and precipitation extremes in the IPCC ensemble of global coupled model simulations , 2007 .

[74]  D. Karoly,et al.  Attribution of Recent Temperature Changes in the Australian Region , 2005 .

[75]  Kenneth R. Sperber,et al.  An Observational Study of the Relationship between Excessively Strong Short Rains in Coastal East Africa and Indian Ocean SST , 2003 .

[76]  C. Ropelewski,et al.  Global and Regional Scale Precipitation Patterns Associated with the El Niño/Southern Oscillation , 1987 .

[77]  S. Yukimoto,et al.  Improvements of the Meteorological Research Institute Global Ocean- atmosphere Coupled GCM (MRI-CGCM2) and its climate sensitivity , 2001 .

[78]  Carlos A. Coelho,et al.  Evidence of trends in daily climate extremes over southern and west Africa , 2006 .

[79]  M. Latif,et al.  The role of Indian Ocean sea surface temperature in forcing east African rainfall anomalies during December-January 1997/98 , 1999 .

[80]  P. Jones,et al.  Representing Twentieth-Century Space-Time Climate Variability. Part II: Development of 1901-96 Monthly Grids of Terrestrial Surface Climate , 2000 .

[81]  I. Kuhnel.  Tropical-extratropical cloudband climatology based on satellite data , 1989 .

[82]  Swadhin K. Behera,et al.  Paramount Impact of the Indian Ocean Dipole on the East African Short Rains: A CGCM Study , 2005 .

[83]  Willem A. Landman,et al.  Climate change 2007 : the physical science basis, S. Solomon, D. Qin, M. Manning, M. Marquis, K. Averyt, M.M.B. Tignor, H. LeRoy Miller, Jr. and Z. Chen (Eds.) : book review , 2010 .

[84]  G. Vecchi,et al.  Global Warming and the Weakening of the Tropical Circulation , 2007 .

[85]  C. Reason,et al.  Sensitivity of the southern African circulation to dipole sea‐surface temperature patterns in the south Indian Ocean , 2002 .

[86]  A. Weaver,et al.  Detecting the effect of climate change on Canadian forest fires , 2004 .

[87]  P. Tyson,et al.  The weather and climate of southern Africa , 2000 .

[88]  Recent climate changes in precipitable water in the global tropics as revealed in National Centers for Environmental Prediction/National Center for Atmospheric Research reanalysis , 2003 .

[89]  S. Mason,et al.  DROUGHTS OVER SOUTHERN AFRICA IN A DOUBLED‐CO2 CLIMATE , 1996 .

[90]  N. Graham,et al.  Importance of the Indian Ocean for simulating rainfall anomalies over eastern and southern Africa , 1999 .

[91]  S. Mason.  El Niño, climate change, and Southern African climate , 2001 .

[92]  L. Greischar,et al.  Atmospheric-hydrospheric mechanisms of climate anomalies in the western equatorial Indian Ocean , 1993 .

[93]  Richard L. Smith,et al.  Regional probabilities of precipitation change: A Bayesian analysis of multimodel simulations , 2004 .

[94]  S. Hastenrath,et al.  Mechanisms of climate anomalies in the equatorial Indian Ocean , 2005 .

[95]  C. Reason,et al.  Tropical Cyclone Eline and its unusual penetration and impacts over the southern African mainland , 2004 .

[96]  James W. Hurrell,et al.  Detection and Attribution of Twentieth-Century Northern and Southern African Rainfall Change , 2006 .

[97]  F. Laio.  Cramer–von Mises and Anderson‐Darling goodness of fit tests for extreme value distributions with unknown parameters , 2004 .