NOAA/WDS Paleoclimatology - Denali, Alaska Snowpit and Firn Core Chemistry Data

STUDY NOTES: Data from 2008 firn core project on Denali. Included are snowpit and firn core chemistry data, automated weather station (AWS) data, and ground penetrating radar (GPR) data. In May 2008, samples were collected from a 4.35m deep snow pit and an 18.77m long, 8.2 cm diameter firn core drilled in the bottom of the pit, approximately 1 km south of Kahiltna Pass (KPass) at 2970m a.s.l, Denali National Park, Alaska. An additional snowpit at the Kahiltna base camp (2195ma.s.l.; 11km south-southeast of KPass) was sampled for chemistry. Hourly AWS data were recorded at the base camp from May 2008 to May 2009, and are included in this data set. Ground penetrating radar (GPR) raw data are presented in 6 .DZT files. GPR images are contained in a Microsoft PowerPoint file. These data plus the snow pit and firn chemistry data are archived at: https://www.ncei.noaa.gov/pub/data/paleo/icecore/trop/denali/
ABSTRACT SUPPLIED BY ORIGINATOR: Samples were collected from a snow pit and shallow firn core near Kahiltna Pass (2970ma.s.l.), Denali National Park, Alaska, USA, in May 2008. The record spans autumn 2003 to spring 2008 and reveals clusters of ice layers interpreted as summertime intervals of above-freezing temperatures. High correlation coefficients (0.75-1.00) between annual ice-layer thickness and regional summertime station temperatures for 4 years (n = 4) indicate ice-layer thickness is a good proxy for mean and extreme summertime temperatures across Alaska, at least over the short period of record. A Rex-block (aka high-over-low) pattern, a downstream trough over Hudson Bay, Canada, and an upstream trough over eastern Siberia occurred during the three melting events that lasted at least 2 weeks. About half of all shorter melting events were associated with a cut-off low traversing the Gulf of Alaska. We hypothesize that a surface-to-bedrock core extracted from this location would provide a high-quality record of summer temperature and atmospheric blocking variability for the last several hundred years.