noaa-icecore-20569 NGRIP Ice Core 120,000 Year Total Air Content Data Eicher, O.; Baumgartner, M.; Schilt, A.; Schmitt, J.; Schwander, J.; Stocker, T.F.; Fischer, H. NGRIP Ice Core 120,000 Year Total Air Content Data 2016-10-06 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/20569 Investigator O. Eicher Investigator M. Baumgartner Investigator A. Schilt Investigator J. Schmitt Investigator J. Schwander Investigator T.F. Stocker Investigator H. Fischer earth science paleoclimate ice cores gas age,null,null,calendar year before present,null,ice cores,null,null,N,AICC2012 earth science paleoclimate ice cores air content,bulk ice,null,milliliter per kilogram,null,ice cores,null,null,N,mL/kg STP earth science paleoclimate ice cores ice age,null,null,calendar year before present,null,ice cores,null,null,N,AICC2012 earth science paleoclimate ice cores air content,bulk ice,unspecified margin of error,milliliter per kilogram,null,ice cores,null,null,N,null earth science paleoclimate ice core atmospheric gas geoscientificInformation Dansgaard-Oeschger cycles 119554 cal yr BP 294 cal yr BP Complete 75.1 75.1 -42.33 -42.33 2917 2917 Continent North America Greenland NGRIP>LATITUDE 75.1>LONGITUDE -42.33 None Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site. English DOC/NOAA/NESDIS/NCEI National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce https://www.ncdc.noaa.gov/data-access/paleoclimatology-data DATA Center Contact Bruce Bauer bruce.a.bauer@noaa.gov paleo@noaa.gov 303-497-6280 303-497-6513

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Boulder CO 80305-3328 USA online ASCII Olivier Eicher, Matthias Baumgartner, Adrian Schilt, Jochen Schmitt, Jakob Schwander, Thomas F. Stocker, and Hubertus Fischer 2016 Climate of the Past 12 10 1979-1993 10.5194/cp-12-1979-2016 https://www.clim-past.net/12/1979/2016/

Because the total air content (TAC) of polar ice is directly affected by the atmospheric pressure and temperature, its record in polar ice cores was initially considered as a proxy for past ice sheet elevation changes. However, the Antarctic ice core TAC record is known to also contain an insolation signature, although the underlying physical mechanisms are still a matter of debate. Here we present a high-resolution TAC record over the whole North Greenland Ice Core Project ice core, covering the last 120000 years, which independently supports an insolation signature in Greenland. Wavelet analysis reveals a clear precession and obliquity signal similar to previous findings on Antarctic TAC, with a different insolation history. In our high-resolution record we also find a decrease of 4-6% (4-5mLkg-1) in TAC as a response to Dansgaard-Oeschger events (DO events). TAC starts to decrease in parallel to increasing Greenland surface temperature and slightly before CH4 reacts to the warming but also shows a two-step decline that lasts for several centuries into the warm interstadial. The TAC response is larger than expected considering only changes in air density by local temperature and atmospheric pressure as a driver, pointing to a transient firnification response caused by the accumulation-induced increase in the load on the firn at bubble close-off, while temperature changes deeper in the firn are still small. STUDY NOTES: North Greenland Ice Core Project (NGRIP) high-resolution Total Air Content (TAC) data for the entire 120,000 year NGRIP record

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/ngrip/gases/ngrip2016tac.txt Data File; NGRIP Ice Core Total Air Content Data USA/NOAA DIF Version 9.8.4 2018-12-11 2018-12-11