TY  - CONF
AU  - Anderson, L.
AU  - Finney, B.P.
AU  - Guldager, N.
AU  - Rover, Jennifer A.
AU  - Shapley, M.D.
AU  - Van Sistine, D.R.
A2  - San Francisco, Calif.
ED  - in
PY  - 2010//
TI  - Oxygen isotopes and hydroclimatic change in the Yukon Flats National Wildlife Refuge, northeast Alaska (Invited) [abs.]
T2  - abstract number GC24B-08
BT  - Fall Meeting
VL  - Fall Meeting Abstracts
PB  - American Geophysical Union
CY  - Washington, D.C.
KW  - Alaska
KW  - area
KW  - boreal
KW  - change
KW  - climate
KW  - conference abstracts
KW  - confluence
KW  - continental
KW  - environment
KW  - evaporation
KW  - flats
KW  - flow
KW  - groundwater
KW  - habitat
KW  - Holocene
KW  - hydrology
KW  - incidence
KW  - isotope
KW  - lake
KW  - landscape
KW  - mineral
KW  - moisture
KW  - mosaic
KW  - natural variation
KW  - permafrost
KW  - reconstruction
KW  - refuge
KW  - resolution
KW  - river
KW  - sampling
KW  - scale
KW  - sediment
KW  - sedimentation
KW  - sensitivity
KW  - summer
KW  - technique
KW  - temperature
KW  - temporal
KW  - topography
KW  - trend
KW  - variation
KW  - water
KW  - water bodies
KW  - wetland
KW  - wildfire
KW  - wildlife
KW  - winter
KW  - Yukon territory
N2  - The Yukon Flats is the region surrounding the confluence of the Porcupine, Sheenjek, Christian, Chandalar, and Yukon Rivers including approximately 20,000 lakes. It is a diverse boreal mosaic landscape (~23,000 km2) that provides spring and summer habitat for over 150 bird species. The climate of the area is continental with severe winter temperatures and warm summers. High effective moisture deficits relative to most boreal environments lead to the unique occurrence of evaporite mineral deposits as well as the highest incidence of naturally occurring wildfires in Alaska. Lake levels are dynamic, and frequently localized, because of subdued topography, varying lake ages and surficial geologic substrates, permafrost extent, and corresponding surface and groundwater flow paths. To better understand the relationships between climate and hydro-environmental change, we are sampling oxygen isotope ratios spatially and temporally. Here we present preliminary GIS-spatial analyses from 108 water bodies and a late Holocene sediment oxygen isotope record from Twelve Mile Lake. We find that the first-order wetland water chemistry relation is with geographic location and hydrologic linkages. A 1.45-m sediment core from 8.8-m water depth was retrieved from Twelve Mile Lake because lake-water ë18O values indicate that evaporation dominates the lake's hydrologic balance and because it is sufficiently alkaline to generate bioinduced endogenic carbonate sedimentation. The sediment ë18O trends during the last millennia have decade-to-century scale temporal resolution and similarities with paleoclimatic trends documented by other lakes in interior regions of Alaska and the Yukon Territory. Results from these preliminary studies reinforce that 1) wetland and lake sensitivity to climate-induced changes in hydrology varies spatially in the Yukon Flats because of dynamic hydrogeographic factors, and 2) recent hydro-environmental changes are better evaluated within a long-term context of past natural variations provided by paleolimnology reconstruction techniques.
SN  - http://www.agu.org/meetings/fm10/waisfm10adv.html
UR  - http://www.agu.org/meetings/fm10/waisfm10adv.html
N1  - exported from refbase (http://eros.usgs.gov/refbase/show.php?record=23332), last updated on Fri, 21 Sep 2012 11:59:54 -0500
ID  - Anderson_etal2010
ER  -