Southern Hemisphere atmospheric history of carbon monoxide over the late Holocene reconstructed from multiple Antarctic ice archives ...

• Main Authors: Faïn, Xavier, Etheridge, David M., Fourteau, Kévin, Martinerie, Patricia, Trudinger, Cathy M., Rhodes, Rachael H., Chellman, Nathan J., Langenfelds, Ray L., McConnell, Joseph R., Curran, Mark A. J., Brook, Edward J., Blunier, Thomas, Teste, Grégory, Grilli, Roberto, Lemoine, Anthony, Sturges, William T., Vannière, Boris, Freitag, Johannes, Chappellaz, Jérôme
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Copernicus Publications 2023
• Subjects: 580 Plants Botany; Antarctic; Antarc*; ice core
• Online Access: https://dx.doi.org/10.48350/198413; https://boris.unibe.ch/198413/

Carbon monoxide (CO) is a naturally occurring atmospheric trace gas, a regulated pollutant, and one of the main components determining the oxidative capacity of the atmosphere. Evaluating climate–chemistry models under different conditions than today and constraining past CO sources requires a reliable record of atmospheric CO mixing ratios ([CO]) that includes data since preindustrial times. Here, we report the first continuous record of atmospheric [CO] for Southern Hemisphere (SH) high latitudes over the past 3 millennia. Our continuous record is a composite of three high-resolution Antarctic ice core gas records and firn air measurements from seven Antarctic locations. The ice core gas [CO] records were measured by continuous flow analysis (CFA), using an optical feedback cavity-enhanced absorption spectrometer (OF-CEAS), achieving excellent external precision (2.8–8.8 ppb; 2σ) and consistently low blanks (ranging from 4.1±1.2 to 7.4±1.4 ppb), thus enabling paleo-atmospheric interpretations. Six new firn ...