Ice sheet-albedo feedback estimated from most recent deglaciation

Booth, Alice, Goodwin, Philip and Cael, B.B. (2024) Ice sheet-albedo feedback estimated from most recent deglaciation. Geophysical Research Letters, 51 (15), [e2024GL109953]. (doi:10.1029/2024GL109953).

Record type: Article

Abstract

Ice sheet feedbacks are underrepresented in model assessments of climate sensitivity and their magnitudes are still poorly constrained. We combine a recently published record of Earth's Energy Imbalance (EEI) with existing reconstructions of temperature, atmospheric composition, and sea level to estimate both the magnitude and timescale of the ice sheet-albedo feedback since the Last Glacial Maximum. This facilitates the first opportunity to quantify this feedback over the most recent deglaciation using a proxy data-driven approach. We find the ice sheet-albedo feedback to be amplifying, increasing the total climate feedback parameter by 42% and reaching an equilibrium magnitude of 0.55 Wm⁻²K⁻¹, with a 66% confidence interval of 0.45–0.63 Wm⁻²K⁻¹. The timescale to equilibrium is estimated as 3.6 ka (66% confidence: 1.9–5.5 ka). These results provide new evidence for the timescale and magnitude of the amplifying ice sheet-albedo feedback that will drive anthropogenic warming for millennia to come.

Text

Geophysical Research Letters - 2024 - Booth - Ice Sheet‐Albedo Feedback Estimated From Most Recent Deglaciation - Version of Record

Available under License Creative Commons Attribution.

Download (1MB)