DOI: 10.1007/s00382-017-3810-y
Scopus记录号: 2-s2.0-85026910896
论文题名: Effects of Arctic geoengineering on precipitation in the tropical monsoon regions
作者: Nalam A. ; Bala G. ; Modak A.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2018
卷: 50, 期: 2018-09-10 起始页码: 3375
结束页码: 3395
语种: 英语
英文关键词: Arctic geoengineering
; Global monsoon regions
; ITCZ shift
; Stratospheric climate change
; Stratospheric sulfate aerosols
Scopus关键词: aerosol
; climate change
; global climate
; intertropical convergence zone
; monsoon
; precipitation (climatology)
; stratosphere
; sulfate
; warming
; Arctic
英文摘要: Arctic geoengineering wherein sunlight absorption is reduced only in the Arctic has been suggested as a remedial measure to counteract the on-going rapid climate change in the Arctic. Several modeling studies have shown that Arctic geoengineering can minimize Arctic warming but will shift the Inter-tropical Convergence Zone (ITCZ) southward, unless offset by comparable geoengineering in the Southern Hemisphere. In this study, we investigate and quantify the implications of this ITCZ shift due to Arctic geoengineering for the global monsoon regions using the Community Atmosphere Model version 4 coupled to a slab ocean model. A doubling of CO2 from pre-industrial levels leads to a warming of ~6 K in the Arctic region and precipitation in the monsoon regions increases by up to ~15%. In our Arctic geoengineering simulation which illustrates a plausible latitudinal distribution of the reduction in sunlight, an addition of sulfate aerosols (11 Mt) in the Arctic stratosphere nearly offsets the Arctic warming due to CO2 doubling but this shifts the ITCZ southward by ~1.5° relative to the pre-industrial climate. The combined effect from this shift and the residual CO2-induced climate change in the tropics is a decrease/increase in annual mean precipitation in the Northern Hemisphere/Southern Hemisphere monsoon regions by up to −12/+17%. Polar geoengineering where sulfate aerosols are prescribed in both the Arctic (10 Mt) and Antarctic (8 Mt) nearly offsets the ITCZ shift due to Arctic geoengineering, but there is still a residual precipitation increase (up to 7%) in most monsoon regions associated with the residual CO2 induced warming in the tropics. The ITCZ shift due to our Global geoengineering simulation, where aerosols (20 Mt) are prescribed uniformly around the globe, is much smaller and the precipitation changes in most monsoon regions are within ±2% as the residual CO2-induced warming in the tropics is also much less than in Arctic and Polar geoengineering. Further, global geoengineering nearly offsets the Arctic warming. Based on our results we infer that Arctic geoengineering leads to ITCZ shift and leaves residual CO2 induced warming in the tropics resulting in substantial precipitation decreases (increases) in the Northern (Southern) hemisphere monsoon regions. © 2017, The Author(s). Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/109330
Appears in Collections: 影响、适应和脆弱性 气候变化事实与影响
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作者单位: Centre for Atmospheric and Oceanic Sciences, Indian Institute of Science, Bangalore, 560012, India
Recommended Citation:
Nalam A.,Bala G.,Modak A.. Effects of Arctic geoengineering on precipitation in the tropical monsoon regions[J]. Climate Dynamics,2018-01-01,50(2018-09-10)