Response of atmospheric CO₂ to the abrupt cooling event 8200 years ago

• Main Authors: Ahn, Jinho, Brook, Edward J., Buizert, Christo
• Format: Article in Journal/Newspaper
• Language: English; unknown
• Published: American Geophysical Union
• Subjects: Siple; Siple Dome; Antarc*; Antarctica; ice core
• Online Access: https://ir.library.oregonstate.edu/concern/articles/hd76s471n

Atmospheric CO₂ records for the centennial scale cooling event 8200 years ago (8.2 ka event) may help us understand climate-carbon cycle feedbacks under interglacial conditions, which are important for understanding future climate, but existing records do not provide enough detail. Here we present a new CO₂ record from the Siple Dome ice core, Antarctica, that covers 7.4–9.0 ka with 8 to 16 year resolution. We observe a small, about 1–2 ppm, increase of atmospheric CO₂ during the 8.2 ka event. The increase is not significant when compared to other centennial variations in the Holocene that are not linked to large temperature changes. Our results do not agree with leaf stomata records that suggest a CO₂ decrease of up to ~25 ppm and imply that the sensitivity of atmospheric CO₂ to the primarily Northern Hemisphere cooling of the 8.2 ka event was limited. Keywords: Carbon cycle, Carbon dioxide, 8.2 ka event, Abrupt climate change