干旱区生态环境知识资源中心(Arid): Deuterium excess and O-17-excess variability in meteoric water across the Pacific Northwest, USA

Arid

DOI	10.1080/16000889.2020.1773722
	Deuterium excess and O-17-excess variability in meteoric water across the Pacific Northwest, USA
	Bershaw, John; Hansen, Dougal D.; Schauer, Andrew J.
通讯作者	Bershaw, J
来源期刊	TELLUS SERIES B-CHEMICAL AND PHYSICAL METEOROLOGY
ISSN	1600-0889
出版年	2020
卷号	72 期号:1
英文摘要	High-precision triple oxygen isotope analysis of water has given rise to a novel second-order parameter, O-17-excess (often denoted as Delta O-17), which describes the deviation from a reference relationship between delta O-18 and delta O-17. This tracer, like deuterium excess (d-excess), is affected by kinetic fractionation (diffusion) during phase changes within the hydrologic cycle. However, unlike d-excess, O-17-excess is present in paleowater proxy minerals and is not thought to vary significantly with temperature. This makes it a promising tool in paleoclimate research, particularly in relatively arid continental regions where traditional approaches have produced equivocal results. We present new delta O-18, delta O-17, and delta H-2 data from stream waters along two east-west transects in the Pacific Northwest to explore the sensitivity of O-17-excess to topography, climate, and moisture source. We find that discrepancies in d-excess and O-17-excess between the Olympic Mountains and Coast Range are consistent with distinct moisture source meteorology, inferred from air-mass back trajectory analysis. We suggest that vapor d-excess is affected by relative humidity and temperature at its oceanic source, whereas O-17-excess vapor is controlled by relative humidity at its oceanic source. Like dexcess, O-17-excess is significantly affected by evaporation in the rain shadow of the Cascade Mountains, supporting its utility as an aridity indicator in paleoclimate studies where delta H-2 data are unavailable. We use a raindrop evaporation model and local meteorology to investigate the effects of subcloud evaporation on dexcess and O-17-excess along altitudinal transects. We find that subcloud evaporation explains much, but not all of observed increases in d-excess with elevation and a minor amount of O-17-excess variation in the Olympic Mountains and Coast Range of Oregon.
英文关键词	stable isotopes meteoric water Pacific Northwest climate atmospheric circulation hydrologic cycle
类型	Article
语种	英语
开放获取类型	Green Published, gold
收录类别	SCI-E
WOS记录号	WOS:000541003100001
WOS关键词	ISOTOPIC COMPOSITION ; STABLE-ISOTOPES ; SURFACE UPLIFT ; PRECIPITATION IMPLICATIONS ; CHAJNANTOR PLATEAU ; RELATIVE-HUMIDITY ; CLOUD EVAPORATION ; CONTINENTAL-SCALE ; TIBETAN PLATEAU ; MOISTURE SOURCE
WOS类目	Meteorology & Atmospheric Sciences
WOS研究方向	Meteorology & Atmospheric Sciences
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/324784
作者单位	[Bershaw, John] Portland State Univ, Portland, OR 97207 USA; [Hansen, Dougal D.] Univ Wisconsin, Madison, WI USA; [Schauer, Andrew J.] Univ Washington, Seattle, WA 98195 USA
推荐引用方式 GB/T 7714	Bershaw, John,Hansen, Dougal D.,Schauer, Andrew J.. Deuterium excess and O-17-excess variability in meteoric water across the Pacific Northwest, USA[J],2020,72(1).
APA	Bershaw, John,Hansen, Dougal D.,&Schauer, Andrew J..(2020).Deuterium excess and O-17-excess variability in meteoric water across the Pacific Northwest, USA.TELLUS SERIES B-CHEMICAL AND PHYSICAL METEOROLOGY,72(1).
MLA	Bershaw, John,et al."Deuterium excess and O-17-excess variability in meteoric water across the Pacific Northwest, USA".TELLUS SERIES B-CHEMICAL AND PHYSICAL METEOROLOGY 72.1(2020).