. (2009). AIRS-based versus flask-based estimation of carbon surface fluxes. J. Geophys. Res., 114(D20), D20303–.
Abstract: This paper demonstrates an inversion of surface CO2 fluxes using concentrations derived from assimilation of satellite radiances. Radiances come from the Atmospheric Infrared Sounder (AIRS) and are assimilated within the system of the European Centre for Medium-Range Weather Forecasts. We evaluate the quality of the inverted fluxes by comparing simulated concentrations with independent airborne measurements. As a benchmark we use an inversion based on surface flask measurements and another using only the global concentration trend. We show that the AIRS-based inversion is able to improve the match to the independent data compared to the prior estimate but that it usually performs worse than either the flask-based or trend-based inversion.
Keywords: CO 2 surface fluxes, inverse method, AIRS satellite data, 0322 Atmospheric Composition and Structure: Constituent sources and sinks, 0428 Biogeosciences: Carbon cycling, 0480 Biogeosciences: Remote sensing, 0365 Atmospheric Composition and Structure: Troposphere: composition and chemistry, 3315 Atmospheric Processes: Data assimilation,
Programme: 416
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Baroni, Mlanie; Savarino, Jol; Cole-Dai, J.; Rai, V.K.; Thiemens, M.H. (2008). Anomalous sulfur isotope compositions of volcanic sulfate over the last millennium in Antarctic ice cores. J. Geophys. Res., 113(D20), D20112.
Abstract: The reconstruction of past volcanism from glaciological archives is based on the measurement of sulfate concentrations in ice. This method does not allow a proper evaluation of the climatic impact of an eruption owing to the uncertainty in classifying an event between stratospheric or tropospheric. This work develops a new method, using anomalous sulfur isotope composition of volcanic sulfate in order to identify stratospheric eruptions over the last millennium. The advantages and limits of this new method are established with the examination of the 10 largest volcanic signals in ice cores from Dome C and South Pole, Antarctica. Of the 10, seven are identified as stratospheric eruptions. Among them, three have been known to be stratospheric (Tambora, Kuwae, the 1259 Unknown Event) and they exhibit anomalous sulfur isotope compositions. Three unknown events (circa 1277, 1230, 1170 A.D.) and the Serua eruption have been identified as stratospheric eruptions, which suggests for the first time that they could have had significant climatic impact. However, the Kuwae and the 1259 Unknown Event stratospheric eruptions exhibit different anomalous sulfur isotope compositions between South Pole and Dome C samples. Differences in sulfate deposition and preservation patterns between the two sites can help explain these discrepancies. This study shows that the presence of an anomalous sulfur isotope composition of volcanic sulfate in ice core indicates a stratospheric eruption, but the absence of such composition does not necessarily lead to the conclusion of a tropospheric process because of differences in the sulfate deposition on the ice sheet.
Keywords: sulfur isotope anomaly; volcanic eruption; ice cores; 0370 Atmospheric Composition and Structure: Volcanic effects; 0454 Biogeosciences: Isotopic composition and chemistry; 0473 Biogeosciences: Paleoclimatology and paleoceanography; 0724 Cryosphere: Ice cores; 1041 Geochemistry: Stable isotope geochemistry
Programme: 1011
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Melanie Baroni, Joel Savarino, Jihong Cole-Dai, Vinai K. Rai and Mark H. Thiemens. (2008). Anomalous sulfur isotope compositions of volcanic sulfate over the last millennium in Antarctic ice cores. J. Geophys. Res., 113, D20112.
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Leroux C., Deuze J.L., Goloub P., Sergent C. & Fily M. (1998). Ground measurements of the polarized bidirectional reflectance of snow in the middle infrared spectral domain: Comparisons with model results. J. Geophys. Res., 103(d16), 19721–11973.
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. (1993). Ionospheric Convection Response to Slow, Strong Variations in a Northward Interplanetary Magnetic Field: A case Study for January 14, 1988. J. Geophys. Res., 98(a11), 19273–19292.
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Petersen A.C., Spee E.J., Van Dop H. & Hundsdorfer W. (1998). An evaluation and intercomparison of four new advection schemes for use in global chemistry models. J. Geophys. Res., 103(d15), 19253–19269.
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Ciais P., White J.W.C., Jouzel J. & Petit J.R. (1995). The origin of present-day Antarctic precipitation from surface snow deuterium excess data. J. Geophys. Res., 100(d9), 18917–18927.
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Tison J.L., Souchez R., Wolff E., Moore J.C., Legrand M. & De Angelis M. (1998). Is a periglacial biota responsible for enhanced dielectric response in banal ice from the greenland Ice Core Project ice core? J. Geophys. Res., 103(d15), 18885–18894.
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Watanabe M., Pinnock M., Rodger A.S., Sato N., Yamagishi H., Yukimatu A.S., Greenwald R.A., Villain J.P. & Hairston M.R. (1998). Localized activation of the distant tail neutral line just prior to substorm onsets. J. Geophys. Res., 103(a8), 17651–17669.
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Davail Sfeller G., Narin X. & Gerday C. (1994). Cold Adaptation of Proteins. Purification, characterization, and sequence of the heat-labile subtilisin from the Antarctic psychrophile bacilus TA41. J. Biol. Chem., 269(26), 17448–17453.
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