气候变化领域集成服务门户(CCPortal): Greenland temperature and precipitation over the last 20 000 years using data assimilation

CCPortal

DOI	10.5194/cp-16-1325-2020
	Greenland temperature and precipitation over the last 20 000 years using data assimilation
	Badgeley J.A.; Steig E.J.; Hakim G.J.; Fudge T.J.
发表日期	2020
ISSN	18149324
起始页码	1325
结束页码	1346
卷号	16 期号:4
英文摘要	Reconstructions of past temperature and precipitation are fundamental to modeling the Greenland Ice Sheet and assessing its sensitivity to climate. Paleoclimate information is sourced from proxy records and climate-model simulations; however, the former are spatially incomplete while the latter are sensitive to model dynamics and boundary conditions. Efforts to combine these sources of information to reconstruct spatial patterns of Greenland climate over glacial-interglacial cycles have been limited by assumptions of fixed spatial patterns and a restricted use of proxy data. We avoid these limitations by using paleoclimate data assimilation to create independent reconstructions of mean-Annual temperature and precipitation for the last 20 000 years. Our method uses oxygen isotope ratios of ice and accumulation rates from long ice-core records and extends this information to all locations across Greenland using spatial relationships derived from a transient climate-model simulation. Standard evaluation metrics for this method show that our results capture climate at locations without ice-core records. Our results differ from previous work in the reconstructed spatial pattern of temperature change during abrupt climate transitions; this indicates a need for additional proxy data and additional transient climate-model simulations. We investigate the relationship between precipitation and temperature, finding that it is frequency dependent and spatially variable, suggesting that thermodynamic scaling methods commonly used in ice-sheet modeling are overly simplistic. Our results demonstrate that paleoclimate data assimilation is a useful tool for reconstructing the spatial and temporal patterns of past climate on timescales relevant to ice sheets. © 2020 Author(s).
语种	英语
scopus关键词	data assimilation; paleoclimate; precipitation (climatology); temperature effect; Arctic; Greenland
来源期刊	Climate of the Past
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/146690
作者单位	Department of Earth and Space Sciences, University of Washington, Seattle, WA, United States; Department of Atmospheric Sciences, University of Washington, Seattle, WA, United States
推荐引用方式 GB/T 7714	Badgeley J.A.,Steig E.J.,Hakim G.J.,et al. Greenland temperature and precipitation over the last 20 000 years using data assimilation[J],2020,16(4).
APA	Badgeley J.A.,Steig E.J.,Hakim G.J.,&Fudge T.J..(2020).Greenland temperature and precipitation over the last 20 000 years using data assimilation.Climate of the Past,16(4).
MLA	Badgeley J.A.,et al."Greenland temperature and precipitation over the last 20 000 years using data assimilation".Climate of the Past 16.4(2020).