Ice record of delta C-13 for atmospheric CH4 across the Younger Dryas-Preboreal transition

Citation:
Schaefer, H, Whiticar MJ, Brook EJ, Petrenko VV, Ferretti DF, Severinghaus JP.  2006.  Ice record of delta C-13 for atmospheric CH4 across the Younger Dryas-Preboreal transition. Science. 313:1109-1112.

Date Published:

Aug

Keywords:

abrupt climate-change, cycle, dynamics, increase, last glacial maximum, methane budget, polar ice

Abstract:

We report atmospheric methane carbon isotope ratios (delta(CH4)-C-13) from the Western Greenland ice margin spanning the Younger Dryas - to - Preboreal (YD-PB) transition. Over the recorded similar to 800 years, delta(CH4)-C-13 was around - 46 per mil (parts per thousand); that is, similar to 1 parts per thousand higher than in the modern atmosphere and similar to 5.5 parts per thousand higher than would be expected from budgets without C-13-rich anthropogenic emissions. This requires higher natural C-13-rich emissions or stronger sink fractionation than conventionally assumed. Constant delta(CH4)-C-13 during the rise in methane concentration at the YD-PB transition is consistent with additional emissions from tropical wetlands, or aerobic plant CH4 production, or with a multisource scenario. A marine clathrate source is unlikely.

Notes:

n/a

Website

DOI:

10.1126/science.1126562