DOI: 10.1016/j.quascirev.2015.07.007
Scopus记录号: 2-s2.0-84949645191
论文题名: Reconstructing paleosalinity from δ18O: Coupled model simulations of the Last Glacial Maximum, Last Interglacial and Late Holocene
作者: Holloway M.D. ; Sime L.C. ; Singarayer J.S. ; Tindall J.C. ; Valdes P.J.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2016
卷: 131 起始页码: 350
结束页码: 364
语种: 英语
英文关键词: Isotopes
; Last Glacial Maximum
; Last Interglacial
; Oxygen-18
; Paleoceanography
; Paleosalinity
Scopus关键词: Budget control
; Glacial geology
; Isotopes
; Oxygen
; Repair
; Sea ice
; Last Glacial Maximum
; Last interglacial
; Oxygen-18
; Paleoceanography
; Paleosalinity
; Oceanography
; computer simulation
; Holocene
; Last Glacial Maximum
; Last Interglacial
; numerical model
; oxygen isotope
; paleoceanography
; paleosalinity
; reconstruction
; Atlantic Ocean
; Atlantic Ocean (North)
; Atlantic Ocean (South)
; Indian Ocean
; Pacific Ocean
; Pacific Ocean (Tropical)
英文摘要: Reconstructions of salinity are used to diagnose changes in the hydrological cycle and ocean circulation. A widely used method of determining past salinity uses oxygen isotope (δOw) residuals after the extraction of the global ice volume and temperature components. This method relies on a constant relationship between δOw and salinity throughout time. Here we use the isotope-enabled fully coupled General Circulation Model (GCM) HadCM3 to test the application of spatially and time-independent relationships in the reconstruction of past ocean salinity. Simulations of the Late Holocene (LH), Last Glacial Maximum (LGM), and Last Interglacial (LIG) climates are performed and benchmarked against existing compilations of stable oxygen isotopes in carbonates (δOc), which primarily reflect δOw and temperature. We find that HadCM3 produces an accurate representation of the surface ocean δOc distribution for the LH and LGM. Our simulations show considerable variability in spatial and temporal δOw-salinity relationships. Spatial gradients are generally shallower but within ~50% of the actual simulated LH to LGM and LH to LIG temporal gradients and temporal gradients calculated from multi-decadal variability are generally shallower than both spatial and actual simulated gradients. The largest sources of uncertainty in salinity reconstructions are found to be caused by changes in regional freshwater budgets, ocean circulation, and sea ice regimes. These can cause errors in salinity estimates exceeding 4 psu. Our results suggest that paleosalinity reconstructions in the South Atlantic, Indian and Tropical Pacific Oceans should be most robust, since these regions exhibit relatively constant δOw-salinity relationships across spatial and temporal scales. Largest uncertainties will affect North Atlantic and high latitude paleosalinity reconstructions. Finally, the results show that it is difficult to generate reliable salinity estimates for regions of dynamic oceanography, such as the North Atlantic, without additional constraints. © 2015 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/59741
Appears in Collections: 过去全球变化的重建
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作者单位: British Antarctic Survey, United Kingdom; School of Geographical Science, University of Bristol, United Kingdom; Department of Meteorology, University of Reading, United Kingdom; School of Earth and Environment, University of Leeds, United Kingdom
Recommended Citation:
Holloway M.D.,Sime L.C.,Singarayer J.S.,et al. Reconstructing paleosalinity from δ18O: Coupled model simulations of the Last Glacial Maximum, Last Interglacial and Late Holocene[J]. Quaternary Science Reviews,2016-01-01,131