Year: 2024
Type: article
Abstract: Holocene temperature evolution remains poorly understood. Proxies in the early and mid‐Holocene suggest a Holocene Thermal Maximum (HTM) where temperatures exceed the pre‐industrial, whereas climate models generally simulate monotonic warming. This discrepancy may reflect proxy seasonality biases or errors in climate model internal feedbacks or dynamics. Using seasonally unbiased ice core reconstructions at NEEM, NGRIP, and Greenland Ice Sheet Project 2, we identify a Greenland HTM of ∼2°C above pre‐industrial, in agreement with other Northern Hemisphere proxy reconstructions. The firn‐based reconstructions are verified through borehole thermometry, producing a multi‐core, multi‐proxy reconstruction of Greenland climate from the last glacial to pre‐industrial. HTM timing across Greenland is heterogenous, occurring earlier at high elevations. Total air content measurements suggest a temperature contribution from elevation changes; regional oceanographic conditions, a weakened polar lapse rate, or variable near‐surface inversions may also be important sensitivities. Our reconstructions support climate simulations with dynamic Holocene vegetation, highlighting the importance of vegetation feedbacks.
Source: Geophysical Research Letters
DOI: 10.1029/2024gl111405
Authors: Kaden C. Martin, Christo Buizert, Ed Brook, Olivia L. Williams, Jon S. Edwards, Ben Riddell‐Young, T. J. Fudge, Farhana Mederbel, Ross Beaudette, Jeff Severinghaus, Ikumi Oyabu, Kenji Kawamura, Marie Kirk, Iben Koldtoft, J. P. Steffensen, Thomas Blunier
Institutions: Oregon State University, Woods Hole Oceanographic Institution, Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, University of Washington, Université de Versailles Saint-Quentin-en-Yvelines, Université Paris-Saclay, Scripps Institution of Oceanography, University of California San Diego, National Institute of Polar Research, Research Organization of Information and Systems, University of Copenhagen
Language: English
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
SDG: Climate action
Open Access status: gold
Estimated APC paid: $2,900
OpenAlex ID: W4405316602