TY - JOUR

T1 - Seasonal temperatures in West Antarctica during the Holocene

AU - Jones, Tyler R.

AU - Cuffey, Kurt M.

AU - Roberts, William H. G.

AU - Markle, Bradley R.

AU - Steig, Eric J.

AU - Stevens, C. Max

AU - Valdes, Paul J.

AU - Fudge, T. J.

AU - Sigl, Michael

AU - Hughes, Abigail G.

AU - Morris, Valerie

AU - Vaughn, Bruce H.

AU - Garland, Joshua

AU - Vinther, Bo M.

AU - Rozmiarek, Kevin S.

AU - Brashear, Chloe A.

AU - White, James W. C.

PY - 2023/1/12

Y1 - 2023/1/12

N2 - The recovery of long-term climate proxy records with seasonal resolution is rare because of natural smoothing processes, discontinuities and limitations in measurement resolution. Yet insolation forcing, a primary driver of multimillennial-scale climate change, acts through seasonal variations with direct impacts on seasonal climate(1). Whether the sensitivity of seasonal climate to insolation matches theoretical predictions has not been assessed over long timescales. Here, we analyse a continuous record of water-isotope ratios from the West Antarctic Ice Sheet Divide ice core to reveal summer and winter temperature changes through the last 11,000 years. Summer temperatures in West Antarctica increased through the early-to-mid-Holocene, reached a peak 4,100 years ago and then decreased to the present. Climate model simulations show that these variations primarily reflect changes in maximum summer insolation, confirming the general connection between seasonal insolation and warming and demonstrating the importance of insolation intensity rather than seasonally integrated insolation or season duration(2,3). Winter temperatures varied less overall, consistent with predictions from insolation forcing, but also fluctuated in the early Holocene, probably owing to changes in meridional heat transport. The magnitudes of summer and winter temperature changes constrain the lowering of the West Antarctic Ice Sheet surface since the early Holocene to less than 162 m and probably less than 58 m, consistent with geological constraints elsewhere in West Antarctica(4-7).

AB - The recovery of long-term climate proxy records with seasonal resolution is rare because of natural smoothing processes, discontinuities and limitations in measurement resolution. Yet insolation forcing, a primary driver of multimillennial-scale climate change, acts through seasonal variations with direct impacts on seasonal climate(1). Whether the sensitivity of seasonal climate to insolation matches theoretical predictions has not been assessed over long timescales. Here, we analyse a continuous record of water-isotope ratios from the West Antarctic Ice Sheet Divide ice core to reveal summer and winter temperature changes through the last 11,000 years. Summer temperatures in West Antarctica increased through the early-to-mid-Holocene, reached a peak 4,100 years ago and then decreased to the present. Climate model simulations show that these variations primarily reflect changes in maximum summer insolation, confirming the general connection between seasonal insolation and warming and demonstrating the importance of insolation intensity rather than seasonally integrated insolation or season duration(2,3). Winter temperatures varied less overall, consistent with predictions from insolation forcing, but also fluctuated in the early Holocene, probably owing to changes in meridional heat transport. The magnitudes of summer and winter temperature changes constrain the lowering of the West Antarctic Ice Sheet surface since the early Holocene to less than 162 m and probably less than 58 m, consistent with geological constraints elsewhere in West Antarctica(4-7).

KW - ICE-SHEET

KW - CLIMATE VARIABILITY

KW - GLACIAL CYCLES

KW - ISOTOPIC DIFFUSION

KW - LATE PLEISTOCENE

KW - SEA-LEVEL

KW - CORE

KW - MODEL

KW - INSOLATION

KW - HISTORY

U2 - 10.1038/s41586-022-05411-8

DO - 10.1038/s41586-022-05411-8

M3 - Journal article

C2 - 36631651

VL - 613

SP - 292

EP - 297

JO - Nature

JF - Nature

SN - 0028-0836

IS - 7943

ER -