Downscaling Last Glacial Maximum climate over southern Africa

QUATERNARY SCIENCE REVIEWS

卷:226

Article

Engelbrecht, Francois A.^1,2,3  Marean, Curtis W.^2,4  Cowling, Richard M.²  Engelbrecht, Christien J.^5,6  Neumann, Frank H.^7,8  Scott, Louis⁹  Nkoana, Ramapulana^3,10  O'Neal, David¹¹  Fisher, Erich⁴  Shook, Eric¹²  Franklin, Janet¹³  Thatcher, Marcus¹⁴  McGregor, John L.¹⁴  Van der Merwe, Jacobus³  Dedekind, Zane^3,15  Difford, Mark² 

[1] Univ Witwatersrand, Global Change Inst, ZA-2050 Johannesburg, South Africa

[2] Nelson Mandela Univ, African Ctr Coastal Palaeosci, ZA-6031 Port Elizabeth, Eastern Cape, South Africa

[3] Council Sci & Ind Res Nat Resources & Environm, ZA-0001 Pretoria, South Africa

[4] Arizona State Univ, Sch Human Evolut & Social Change, Inst Human Origins, Tempe, AZ 85287 USA

[5] Agr Res Council, Inst Soil Climate & Water, Pretoria, South Africa

[6] Univ Pretoria, Dept Geog Geoinformat & Meteorol, Pretoria, South Africa

[7] Univ Witwatersrand, Evolutionary Studies Inst, ZA-2050 Johannesburg, South Africa

[8] Univ Witwatersrand, Sch Geosci, ZA-2050 Johannesburg, South Africa

[9] Univ Free State, Dept Plant Sci, Nelson Mandela Dr, ZA-9301 Bloemfontein, South Africa

[10] Univ Witwatersrand, Sch Geog Archaeol & Environm Studies, Johannesburg, South Africa

[11] Carnegie Mellon Univ, Pittsburgh Supercomp Ctr, Pittsburgh, PA 15213 USA

[12] Univ Minnesota, Dept Geog Environm & Soc, Minneapolis, MN 55455 USA

[13] Univ Calif Riverside, Dept Bot & Plant Sci, Riverside, CA 95521 USA

[14] Commonwealth Sci & Ind Res Org CSIRO Oceans & A, Aspendale, Vic, Australia

[15] Swiss Fed Inst Technol, Zurich, Switzerland

关键词: Pleistocene;    Palaeoclimate modelling;    Climate dynamics;    Vegetation dynamics;    Southern Africa;    Palaeo-agulhas plain;    Rainfall seasonality;    Regional climate modelling;   

DOI  :  10.1016/j.quascirev.2019.105879

来源: Elsevier

【 摘 要 】

We conducted the first dynamic downscaling of Last Glacial Maximum (LGM) climate over southern Africa using a regional climate model. Eight coupled global climate model (CGCM) projections of LGM climate were downscaled to 8 km resolution, and compared to a downscaling of present-day climate. it is projected that temperatures were significantly lower during the LGM compared to the present-day, with annual average temperatures 4-6 degrees C lower along the eastern escarpment, south-north aligned Cape Fold Mountains and western escarpment. Southern Africa is projected to have been generally wetter during the LGM, with a significant extension in the northward reach of frontal rainfall. The largest rainfall increases are projected for the south-north aligned Cape Fold Mountains and the western escarpment of South Africa, but with rainfall decreases projected for the Cape south coast region. Rainfall seasonality is projected to have been significantly different from that of the present-day, with an all-year rainfall region plausibly extending as far north and east as the present-day Free State and Gauteng provinces of South Africa. Evaluations of the downscalings against key published proxy records for the LGM from southern Africa suggest good agreement and few deviations. (C) 2019 Published by Elsevier Ltd.

【 授权许可】

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