A New Ice Core from the Devon Ice Cap Canadian Arctic: Continued Development of High-resolution Proxy Records to Evaluate the Regionalization of Climate in the Circum-Arctic
The primary goal of this project was to collect an ice core from the Summit of the Devon Ice Cap, Devon Island, Canadian Arctic. A 302-m core was collected during the spring of 1998 with additional field work in 1999. Individuals supported by this grant participated in the field work, although the G...
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| Format: | Text |
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DigitalCommons@UMaine
2002
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| Online Access: | https://digitalcommons.library.umaine.edu/orsp_reports/125 https://digitalcommons.library.umaine.edu/cgi/viewcontent.cgi?article=1131&context=orsp_reports |
| Summary: | The primary goal of this project was to collect an ice core from the Summit of the Devon Ice Cap, Devon Island, Canadian Arctic. A 302-m core was collected during the spring of 1998 with additional field work in 1999. Individuals supported by this grant participated in the field work, although the GSC did the actual drilling. Glacier flow models as well as physical characteristics of the ice and d18O records suggest that basal ice recovered is about 86,000 years old. The first 200 meters were collected under dry drilling conditions, whereas the final 52 meters were collected with a drilling fluid to help prevent microfractures in the core. Unfortunately, drilling fluid penetrated to the interior of the core through microfractures, thus the bottom 52 meters was unable to be measured for the parameters analyzed in this study. Ice spanning approximately the last 5000 years was analyzed. To establish base-line conditions (i.e., modern snow characteristics), four snow pits were dug during the two field seasons. The same measurements were performed on pit snow as were done for ice and firn collected in the coring process. Two main parameters were measured, ice glaciochemistry and concentrations of insoluble microparticles. Concentrations of major anions (Cl-, NO3-, SO42-), major cations (Na+, NH4+, K+, Mg2+, Ca2+) and MSA were determined using a DionexÖ Model 2010 ion chromatograph with an auto sample housed in a designated laboratory. Insoluble particle concentrations and grain-size distributions from 0.6 to 13 Ám in 64 logarithmically-divided channels were determined with an Elzone 280 PC particle counter equipped with a 30 Ám orifice in a Class 100 clean room. A new microparticle analyzer had to be purchased near the end of the award period, as the electronics used in the original machine are now out of date. The mircoparticle record has just been completed, thus the evaluation of that record has yet to be undertaken. There were no direct educational activities except for general outreach via lectures as summarized ... |
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