气候变化领域集成服务门户(CCPortal): Process-oriented assessment of RCA4 regional climate model projections over the Congo Basin under 1.5∘C and 2∘C global warming levels: influence of regional moisture fluxes

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DOI	10.1007/s00382-019-04751-y
	Process-oriented assessment of RCA4 regional climate model projections over the Congo Basin under 1.5∘C and 2∘C global warming levels: influence of regional moisture fluxes
	Tamoffo A.T.; Moufouma-Okia W.; Dosio A.; James R.; Pokam W.M.; Vondou D.A.; Fotso-Nguemo T.C.; Guenang G.M.; Kamsu-Tamo P.H.; Nikulin G.; Longandjo G.-N.; Lennard C.J.; Bell J.-P.; Takong R.R.; Haensler A.; Tchotchou L.A.D.; Nouayou R.
发表日期	2019
ISSN	0930-7575
起始页码	1911
结束页码	1935
卷号	53 期号:2020-03-04
英文摘要	Understanding the processes responsible for precipitation and its future change is important to develop plausible and sustainable climate change adaptation strategies, especially in regions with few available observed data like Congo Basin (CB). This paper investigates the atmospheric circulation processes associated with climate model biases in CB rainfall, and explores drivers of projected rainfall changes. Here we use an ensemble of simulations from the Swedish Regional Climate Model (RCM) RCA4, driven by eight General Circulation Models (GCMs) from the Coupled Model Intercomparison Project Phase 5 (CMIP5), for the 1.5∘C and 2∘C global warming levels (GWLs), and under the representative concentration pathways (RCPs) 4.5 and 8.5. RCA4 captures reasonably well the observed patterns of CB rainfall seasonality, but shows dry biases independent of seasons and large scale driving atmospheric conditions. While simulations mimic observed peaks in transition seasons (March–May and September–November), the rain-belt is misplaced southward (northward) in December–February (June–August), reducing the latitudinal extent of rainfall. Moreover, ERA-Interim reanalysis driven RCM simulation and RCM–GCM combinations show similar results, indicating the dominance of systematic biases. Modelled dry biases are associated with dry upper-tropospheric layers, resulting from a western outflow stronger than the eastern inflow and related to the northern component of African Easterly Jet. From the analysis of the climate change signal, we found that regional scale responses to anthropogenic forcings vary across GWLs and seasons. Changes of rainfall and moisture divergence are correlated, with values higher in March–May than in September–November, and larger for global warming of 2.0∘C than at 1.5∘C. There is an increase of zonal moisture divergence fluxes in upper atmospheric layers (>700hPa) under RCP8.5 compared to RCP4.5. Moreover, it is found that additional warming of 0.5∘C will change the hydrological cycle and water availability in the CB, with potential to cause challenges to water resource management, agriculture, hydro-power generation, sanitation and ecosystems. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	CMIP5; Congo Basin rainfall biases; Global warming levels; Moisture convergence; RCA4; RCPs
语种	英语
scopus关键词	climate modeling; climate prediction; convergence; ensemble forecasting; general circulation model; global warming; hydrological cycle; rainfall; regional climate; temporal variation; water availability; Congo Basin
来源期刊	Climate Dynamics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/146125
作者单位	Laboratory for Environmental Modelling and Atmospheric Physics (LEMAP), Department of Physics, University of Yaounde 1, P.O. Box 812, Yaounde, Cameroon; 2LMI DYCOFAC (IRD, University of Yaounde 1, IRGM), IRD, BP1857, Yaoundé, Cameroon; Universite Paris Saclay, Intergovernmental Panel on Climate Change (IPCC) Working Group 1 (WG1) Technical Support Unit (TSU), Saint Aubin, France; European Commission, Joint Research Centre (JRC), Ispra, Italy; Environmental Change Institute, University of Oxford, Oxford, United Kingdom; Department of Physics, Higher Teacher Training College, University of Yaounde 1, P.O. Box 47, Yaounde, Cameroon; Climate Change Research Laboratory (CCRL), National Institute of Cartography, P.O. Box 157, Yaounde, Cameroon; Laboratory of Mechanics and Modeling of Physical Systems, Department of Physics, Faculty of Science, University of Dschang, Po Box 67, Dschang, Cameroon; Climate Prediction Center, National Centers for Environmental Predictions, National Oceanic and Atmospheric Administr...
推荐引用方式 GB/T 7714	Tamoffo A.T.,Moufouma-Okia W.,Dosio A.,et al. Process-oriented assessment of RCA4 regional climate model projections over the Congo Basin under 1.5∘C and 2∘C global warming levels: influence of regional moisture fluxes[J],2019,53(2020-03-04).
APA	Tamoffo A.T..,Moufouma-Okia W..,Dosio A..,James R..,Pokam W.M..,...&Nouayou R..(2019).Process-oriented assessment of RCA4 regional climate model projections over the Congo Basin under 1.5∘C and 2∘C global warming levels: influence of regional moisture fluxes.Climate Dynamics,53(2020-03-04).
MLA	Tamoffo A.T.,et al."Process-oriented assessment of RCA4 regional climate model projections over the Congo Basin under 1.5∘C and 2∘C global warming levels: influence of regional moisture fluxes".Climate Dynamics 53.2020-03-04(2019).