Alpine permafrost could account for a quarter of thawed carbon based on Plio-Pleistocene paleoclimate analogue

Abstract

Estimates of the permafrost-climate feedback vary in magnitude and sign, partly because permafrost carbon stability in warmer-than-present conditions is not well constrained. Here we use a Plio-Pleistocene lacustrine reconstruction of mean annual air temperature (MAAT) from the Tibetan Plateau, the largest alpine permafrost region on the Earth, to constrain past and future changes in permafrost carbon storage. Clumped isotope-temperatures (Δ47-T) indicate warmer MAAT (~1.2 °C) prior to 2.7 Ma, and support a permafrost-free environment on the northern Tibetan Plateau in a warmer-than-present climate. Δ47-T indicate ~8.1 °C cooling from 2.7 Ma, coincident with Northern Hemisphere glacial intensification. Combined with climate models and global permafrost distribution, these results indicate, under conditions similar to mid-Pliocene Warm period (3.3–3.0 Ma), ~60% of alpine permafrost containing ~85 petagrams of carbon may be vulnerable to thawing compared to ~20% of circumarctic permafrost. This estimate highlights ~25% of permafrost carbon and the permafrost-climate feedback could originate in alpine areas.

Qinghai‐Tibet Plateau Permafrost at Risk in the Late 21st Century

“…These changes pose significant impacts on ecology, hydrology, biogeochemistry, and engineering infrastructure on the third pole and surrounding areas (Song et al., 2022; W. Wang et al., 2018; Xiang et al., 2016; Yang et al., 2018). Particularly, permafrost thawing can trigger the release of soil organic carbon (SOC) into the atmosphere, which in turn affects climate warming (Burke et al., 2012; F. Cheng et al., 2022; DeConto et al., 2012; MacDougall et al., 2012; Mu et al., 2020; T. Wang et al., 2020). In addition, permafrost degradation can cause massive ground ice melting and alter river flow regimes.…”

“…Wang et al, 2018;Xiang et al, 2016;Yang et al, 2018). Particularly, permafrost thawing can trigger the release of soil organic carbon (SOC) into the atmosphere, which in turn affects climate warming (Burke et al, 2012;F. Cheng et al, 2022;DeConto et al, 2012;MacDougall et al, 2012;Mu et al, 2020;T.…”

Permafrost in the Cretaceous supergreenhouse

“…60% of alpine permafrost is vulnerable to thawing compared to ca. 20% of circumarctic permafrost 77 . These authors estimated that ca.…”

“…These authors estimated that ca. 25% of permafrost carbon and the permafrost–climate feedback could arise from alpine areas 77 .…”

We Must Stop Fossil Fuel Emissions to Protect Permafrost Ecosystems

“…Persistent uncertainty about permafrost processes does not limit our ability to act now to protect the permafrost domain. Across traditional, modeled, and empirical approaches, there is consensus that the timing and degree of damage to the permafrost domain are directly associated with the amount of human-caused warming (Canadell et al, 2021;Abbott B. W., 2022;Cheng et al, 2022;Fewster et al, 2022). The question then becomes, how can we most effectively reduce anthropogenic climate change?…”