African climate change: 1900-2100

Climate Research

Todd Ngara¹  Ruth Doherty¹  David Lister¹  Mike Hulme¹  Mark New¹ 

关键词: African climate;    Climate scenarios;    Rainfall variability;    Climate modelling;    Seasonal forecasting;    Land cover changes;   

DOI  :  10.3354/cr017145

来源: Inter-Research Science Publishing

【 摘 要 】

ABSTRACT: This paper reviews observed (1900-2000) and possible future (2000-2100) continent-wide changes in temperature and rainfall for Africa. For the historic period we draw upon a new observed global climate data set which allows us to explore aspectsof regional climate change related to diurnal temperature range and rainfall variability. The latter includes an investigation of regions where seasonal rainfall is sensitive to El Niño climate variability. This review of past climate change provides thecontext for our scenarios of future greenhouse gas-induced climate change in Africa. These scenarios draw upon the draft emissions scenarios prepared for the Intergovernmental Panel on Climate Change¹s Third Assessment Report, a suite of recent globalclimate model experiments, and a simple climate model to link these 2 sets of analyses. We present a range of 4 climate futures for Africa, focusing on changes in both continental and regional seasonal-mean temperature and rainfall. Estimates ofassociated changes in global CO₂ concentration and global-mean sea-level change are also supplied. These scenarios draw upon some of the most recent climate modelling work. We also identify some fundamental limitations to knowledge with regardto future African climate. These include the often poor representation of El Niño climate variability in global climate models, and the absence in these models of any representation of regional changes in land cover and dust and biomass aerosol loadings.These omitted processes may well have important consequences for future African climates, especially at regional scales. We conclude by discussing the value of the sort of climate change scenarios presented here and how best they should be used innational and regional vulnerability and adaptation assessments.

【 授权许可】

Unknown