DOI: 10.1016/j.quascirev.2018.08.004
Scopus记录号: 2-s2.0-85051033867
论文题名: High-and low-latitude forcing of the East African climate since the LGM: Inferred from the elemental composition of marine sediments off Tanzania
作者: Liu X. ; Rendle-Bühring R. ; Henrich R.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2018
卷: 196 起始页码: 124
结束页码: 136
语种: 英语
英文关键词: African Humid Period
; Heinrich stadial 1
; Paleoclimatology
; X-ray fluorescence scanner
; Younger Dryas
Scopus关键词: Catchments
; Drought
; Fluorescence
; Geochemistry
; Incident solar radiation
; Scanning
; Submarine geology
; X rays
; Heinrich stadial 1
; Humid periods
; Paleoclimatology
; X ray fluorescence
; Younger Dryas
; Sediments
; catchment
; chemical element
; climate forcing
; Heinrich event
; Holocene
; humid environment
; interstadial
; intertropical convergence zone
; isotopic ratio
; Last Glacial Maximum
; marine sediment
; Northern Hemisphere
; paleoclimate
; reconstruction
; scanner
; sediment core
; X-ray fluorescence
; Younger Dryas
; Rufiji River
; Tanzania
英文摘要: We present X-Ray Fluorescence (XRF) Scanner measurements from a 6 m long sediment core (GeoB12624-1) on the upper slope of Tanzania to reconstruct the climatic evolution in East Africa since the Last Glacial Maximum (LGM). Log-ratios of Fe/Ca and Ti/Ca are indicative for sediment discharge of the Rufiji River, which is controlled by climatic conditions in the Rufiji catchment area. The most significant changes in major elemental composition occurred at 15.1 and 7.4 ka highlighted by the regime shift index values. The data set records distinct precipitation peaks during the early Holocene. This corresponds a maximum in the Northern Hemisphere (NH) summer insolation and results in a transition from the arid LGM to the humid early Holocene. Our geochemical record also indicates that this climatic transition was interrupted by two severe droughts that occurred during NH cold intervals: the Heinrich stadial 1 (HS1) and the Younger Dryas (YD). Through a comparison with other nearby paleoclimatic records, we suggest that arid climatic conditions only occurred in East Africa north of 8–10°S, whereas in southern East Africa around 15–20°S increased humidity during the HS1 and YD prevailed. We thus conclude that these two drought events were caused by a southward migration of the Intertropical Convergence Zone (ITCZ) which was fostered by the NH cooling during the HS1 and YD. Hence, our new geochemical record clearly documents that the East African climate not only responded to low-latitude insolation forcing on sub-orbital time scales, but also, was strongly influenced by high-latitude cooling during the HS1 and YD periods. © 2018 Elsevier Ltd Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/112083
Appears in Collections: 气候减缓与适应
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作者单位: Key Laboratory of Submarine Geosciences and Prospecting Technology, College of Marine Geosciences, Ocean University of China, Qingdao, 266100, China; Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266061, China; MARUM – Center for Marine Environmental Sciences and Faculty of Geosciences, University of Bremen, Bremen, D-28359, Germany
Recommended Citation:
Liu X.,Rendle-Bühring R.,Henrich R.. High-and low-latitude forcing of the East African climate since the LGM: Inferred from the elemental composition of marine sediments off Tanzania[J]. Quaternary Science Reviews,2018-01-01,196