DOI: 10.5194/cp-8-1323-2012
Scopus记录号: 2-s2.0-84871649934
论文题名: Drastic shrinking of the Hadley circulation during the mid-Cretaceous Supergreenhouse
作者: Hasegawa H. ; Tada R. ; Jiang X. ; Suganuma Y. ; Imsamut S. ; Charusiri P. ; Ichinnorov N. ; Khand Y.
刊名: Climate of the Past
ISSN: 18149324
出版年: 2012
卷: 8, 期: 4 起始页码: 1323
结束页码: 1337
语种: 英语
Scopus关键词: atmospheric circulation
; Cretaceous
; data set
; global climate
; Hadley cell
; heat transfer
; latitude
; meridional circulation
; paleoatmosphere
; paleoclimate
; proxy climate record
; reconstruction
; subtropical region
; surface wind
; temperature gradient
; threshold
; Asia
英文摘要: Understanding the behavior of the global climate system during extremely warm periods is one of the major themes of paleoclimatology. Proxy data demonstrate that the equator-to-pole temperature gradient was much lower during the mid-Cretaceous "supergreenhouse" period than at present, implying larger meridional heat transport by atmospheric and/or oceanic circulation. However, reconstructions of atmospheric circulation during the Cretaceous have been hampered by a lack of appropriate datasets based on reliable proxies. Desert distribution directly reflects the position of the subtropical high-pressure belt, and the prevailing surface-wind pattern preserved in desert deposits reveals the exact position of its divergence axis, which marks the poleward margin of the Hadley circulation. We reconstructed temporal changes in the latitude of the subtropical high-pressure belt and its divergence axis during the Cretaceous based on spatio-temporal changes in the latitudinal distribution of deserts and prevailing surface-wind patterns in the Asian interior. We found a poleward shift in the subtropical high-pressure belt during the early and late Cretaceous, suggesting a poleward expansion of the Hadley circulation. In contrast, an equatorward shift of the belt was found during the mid-Cretaceous "supergreenhouse" period, suggesting drastic shrinking of the Hadley circulation. These results, in conjunction with recent observations, suggest the existence of a threshold in atmospheric CO2 level and/or global temperature, beyond which the Hadley circulation shrinks drastically. © Author(s) 2012. 资助项目: JSPS, Japan Society for the Promotion of Science
; JSPS, Japan Society for the Promotion of Science
; NSFC, National Natural Science Foundation of China
Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/49539
Appears in Collections: 气候变化与战略
There are no files associated with this item.
Recommended Citation:
Hasegawa H.,Tada R.,Jiang X.,et al. Drastic shrinking of the Hadley circulation during the mid-Cretaceous Supergreenhouse[J]. Climate of the Past,2012-01-01,8(4)