Filters: Tags: {"scheme":"ISO 19115 Topic Category"} (X) > partyWithName: Lesleigh Anderson (X) > partyWithName: U.S. Geological Survey - ScienceBase (X)
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Andrews Meadow in the Loch Vale watershed, Rocky Mountain National Park. Sample Collection: Englemann spruce (Picea engelmannii) living on slopes surrounding and at the edge of Andrews meadow (Latitude 40˚ 17’ 24” N, Longitude 105˚ 40’ 01” W NAD83). At the time of collection, the climate-sensitive upland P. engelmannii trees were growing on well-drained slopes above the meadow. Seventeen trees, two cores per tree when possible, were collected using a 5mm-diameter increment borer. During sample collection, diameter at breast height (DBH) was also measured. These cores were processed following standard dendrochronological methods. The annual (TW) and earlywood (EW) ring-widths of each core were measured to 0.001mm...
During recent decades, lake levels in the Yukon Flats region of interior Alaska have fluctuated dramatically. However, prior to recorded observations, no data are available to indicate if similar or more extreme variations occurred during past centuries and millennia. This study explores the history of Yukon Flats lake origins and lake levels for the past approximately 5,500 years from sediment analyses guided by previous work on permafrost extent, thermokarst, and modern isotope hydrology. Sediments dated by 210Pb and AMS radiocarbon indicate stable chronologies following initial lake initiation. Subsequent lithology is autochthonous, and oxygen isotope ratios of endogenic carbonate reflect lake level change at...
Categories: Data;
Tags: Alaska,
Holocene,
Land Use Change,
USGS Science Data Catalog (SDC),
Yukon Flats,
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