Reconstruction of the undiffused seasonal oxygen isotope signal in central Greenland ice cores
2000 (English)In: JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, ISSN 0148-0227, Vol. 105, no C9, 22095-22106 p.Article in journal (Refereed) Published
The climatologically important seasonal signal in ice core oxygen isotope records is altered by diffusion with time. Here we use the diffusion model of Whillans and Grootes  to calculate the effects of isotopic diffusion in nine shallow ice cores recovered over a 150 x 150 km grid centered on Summit, Greenland. Two different computational methods give similar results for the back-diffused delta(18)O seasonal extrema. Although back diffusing the ice core delta(18)O records improves the correlations between the individual ice core oxygen isotope and Greenland coastal temperature records; the correlations remain poor, particularly for the low-accumulation sites. Stacking the back-diffused isotopic records from several cores results in much higher correlations, with a strong winter linkage between west coast stations and central Greenland. These correlations are also significantly greater than the correlations between the stacked measured (diffused) isotopic profiles and coastal temperatures. Our results indicate that the use of ice core isotopic records to identify anomalous seasons requires that diffusion effects be accounted for.
Place, publisher, year, edition, pages
2000. Vol. 105, no C9, 22095-22106 p.
ATMOSPHERIC CIRCULATION; ACCUMULATION; CLIMATE; PRECIPITATION; SUMMIT; SNOW; TEMPERATURE; DELTA-O-18; VARIABILITY; ANTARCTICA
IdentifiersURN: urn:nbn:se:uu:diva-37686OAI: oai:DiVA.org:uu-37686DiVA: diva2:65585
Addresses: Bolzan JF, Uppsala Univ, Dept Earth Sci, Villavagen 16, S-75236 Uppsala, Sweden. Uppsala Univ, Dept Earth Sci, S-75236 Uppsala, Sweden. Ohio State Univ, Byrd Polar Res Ctr, Columbus, OH 43210 USA.2005-04-192005-04-192011-01-14