Title Patterns of CO2 and radiocarbon across high northern latitudes during International Polar Year 2008
Author Vay, S.A.; Choi, Y.; Vadrevu, K.P.; Blake, D.R.; Tyler, S.C.; Wisthaler, A.; Hecobian, A.; Kondo, Y.; Diskin, G.S.; Sachse, G.W.; Woo, J.H.; Weinheimer, A.J.; Burkhart, J.F.; Stohl, A.; Wennberg, P.O.
Author Affil Vay, S.A., NASA Langley Research Center, Chemistry and Dynamics Branch, Hampton, VA. Other: National Institute of Aerospace; University of Maryland; University of California at Irvine; University of Innsbruck, Austria; Georgia Institute of Technology; University of Tokyo, Japan; Konkuk University, South Korea; National Center for Atmospheric Research; Norwegian Institute for Air Research, Norway; California Institute of Technology
Source Journal of Geophysical Research, 116(D14), Citation D14301. Publisher: American Geophysical Union, Washington, DC, United States. ISSN: 0148- 0227
Publication Date 2011
Notes In English. 45 refs. CRREL Acc. No: 66001787
Index Terms atmospheric circulation; carbon isotopes; chemical composition; geochemical cycles; human activity; isotopes; radioactive isotopes; subpolar regions; Arctic Ocean; Arctic region; Northern Hemisphere; atmosphere; black carbon; C-14; carbon; carbon cycle; carbon dioxide; carbon monoxide; geochemical cycle; International Polar Year 2007-08; IPY 2007-08 Research Publications; subarctic regions
Abstract High-resolution in situ CO2 measurements were conducted aboard the NASA DC-8 aircraft during the ARCTAS/POLARCAT field campaign, a component of the wider 2007- 2008 International Polar Year activities. Data were recorded during large-scale surveys spanning the North American sub-Arctic to the North Pole from 0.04 to 12 km altitude in spring and summer of 2008. Influences on the observed CO2 concentrations were investigated using coincident CO, black carbon, CH3CN, HCN, O3, C2Cl4, and Delta 14CO2 data, and the FLEXPART model. In spring, the CO2 spatial distribution from 55N to 90N was largely determined by the long-range transport of air masses laden with Asian anthropogenic pollution intermingled with Eurasian fire emissions evidenced by the greater variability in the mid-to-upper troposphere. At the receptor site, the enhancement ratios of CO2 to CO in pollution plumes ranged from 27 to 80 ppmv ppmv-1 with the highest anthropogenic content registered in plumes sampled poleward of 80N. In summer, the CO2 signal largely reflected emissions from lightning-ignited wildfires within the boreal forests of northern Saskatchewan juxtaposed with uptake by the terrestrial biosphere. Measurements within fresh fire plumes yielded CO2 to CO emission ratios of 4 to 16 ppmv ppmv-1 and a mean CO2 emission factor of 1698 280 g kg-1 dry matter. From the 14C in CO2 content of 48 whole air samples, mean spring (46.6 4.4 ppm) and summer (51.5 5 ppm) Delta 14CO2 values indicate a 5 ppm seasonal difference. Although the northern midlatitudes were identified as the emissions source regions for the majority of the spring samples, depleted Delta 14CO2 values were observed in 1% of the data set. Rather, ARCTAS Delta 14CO2 observations (54%) revealed predominately a pattern of positive disequilibrium (1-7 ppm) with respect to background regardless of season owing to both heterotrophic respiration and fire-induced combustion of biomass. Anomalously enriched Delta 14CO2 values (101-262 ppm) measured in emissions from Lake Athabasca and Eurasian fires speak to biomass burning as an increasingly important contributor to the mass excess in Delta 14CO2 observations in a warming Arctic, representing an additional source of uncertainty in the quantification of fossil fuel CO2.
URL http://hdl.handle.net/10.1029/2011JD015643
Publication Type journal article
Record ID 312140