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Gas analyses were measured to reconstruct the 15Nitrogen/14Nitrogen (d15N) anomaly associated with the abrupt warming episodes better known as the Dansgaard-Oeschger (DO) events. In addition to the d15N analyses, we measured the elemental composition of Oxygen, Nitrogen and Argon in order to assess the magnitude of gas loss from the core which was drilled in 1981. The Dye 3 d15N data exhibit larger excursions than d15N data from any other ice core (Greenland or Antarctica). Taken at face value, larger d15N excursions imply larger abrupt temperature increases during the warming phases of the DO events.
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EGRIP PSU gas data on warming events
Abrupt warming episodes during the last glacial termination were sampled from the EGRIP ice core. These ice samples were processed for elemental and isotopic gas measurements at Penn State. d15N data will be used to calibrate the warming episodes during the transition.
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- Award ID(s):
- 1804133
- PAR ID:
- 10485516
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- Temperature
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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