| Title | Meteorological snow chemistry relationships at Divide Site, St. Elias Mountains, Yukon Territory |
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| Author | Vogan, N W; Kreutz, K J; Wake, C P; Zdanowicz, C M ; Copland, L; Fisher, D; Osterberg, E; Wanamaker, A; Yalcin, K |
| Source | Eos, Transactions of the American Geophysical Union vol. 87, no. 52, 2006, 1 pages |
| Links | Online - En ligne
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| Image |  |
| Year | 2006 |
| Alt Series | Earth Sciences Sector, Contribution Series 20080617 |
| Meeting | American Geophysical Union, Fall meeting; San Francisco; US; December 11-15, 2006 |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| Province | Yukon |
| NTS | 115C |
| Area | St. Elias Mountains; Mount Logan; Eclipse Icefield |
| Lat/Long WENS | -142.0000 -140.0000 61.0000 60.0000 |
| Subjects | surficial geology/geomorphology; ice; ice conditions; snow; precipitation; cores; core analysis; atmospheric geochemistry; sediment transport; transport mechanisms; transportation |
| Released | 2006 01 01 |
| Abstract | A new ice core (343 m) was collected from the Eclipse Icefield (~30 km northeast of the Logan Massif, 3017 masl) in the St. Elias Mountains in 2001-02. Previous work on snow samples and an ice core
recovered in 1980 from Mt. Logan (5345 masl) has shown that major discontinuities in the variation of the water stable isotope ratios exist with altitude, which are believed to be derived from a multilayered atmosphere during precipitation events on
high altitude glacier sites. To properly interpret the glaciochemical records developed from the new Eclipse Icefield ice cores, calibration of snow properties with meteorological data (temperature, precipitation, and sea level pressure) is critical.
At the Divide Site (2800 masl), two automatic weather stations (AWS) have been operating since 2002, collecting snow depth as well as standard meteorological data. Based on the AWS data from 2002-2005, the site has a mean annual temperature of -9°C
with an average wind speed of 21 km/hr and a mean atmospheric pressure of 726 mb. The winter accumulation seasons (August-April) of 2002-03, 2003-04, 2005-06 result in ~4m of snow (~2m w.e.) with a net surface height change of ~2m over the balanced
year (August-August) thereby allowing discrete subannual isotopic records. Accumulating snow from 2002-03 and 2003-04 has an average isotopic composition of -186(permil) (SMOW) deltaD and -24(permil) (SMOW) delta18O. We will present a detailed
analysis of the accumulation record at the site from 2003 to 2006 in order to identify the individual snowfall events. We will discuss the changes in the isotopic composition between these snowfall events and determine the relative control that
variability in the local meteorological conditions at the time of precipitation and broader scale changes in atmospheric circulation and moisture transport have on stable water isotopes in precipitation in the St. Elias Mountains. |
| GEOSCAN ID | 226303 |
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