J 2023

Active layer and permafrost thermal regimes in the ice-free areas of Antarctica

HRBÁČEK, Filip, Marc OLIVA, Christel HANSEN, Megan BALKS, Tanya Ann O'NEILL et. al.

Basic information

Original name

Active layer and permafrost thermal regimes in the ice-free areas of Antarctica

Authors

HRBÁČEK, Filip (203 Czech Republic, guarantor, belonging to the institution), Marc OLIVA, Christel HANSEN, Megan BALKS, Tanya Ann O'NEILL, de Pablo Miguel ANGEL, Stefano PONTI, Miguel RAMOS, Goncalo VIEIRA, Andrey ABRAMOV, Lucia KAPLAN PASTÍRIKOVÁ (703 Slovakia, belonging to the institution), Mauro GUGLIELMIN, Gabriel GOYANES, Marcio Rocha FRANCELINO, Carlos SCHAEFER and Denis LACELLE

Edition

Earth-Science Reviews, Elsevier, 2023, 0012-8252

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10510 Climatic research

Country of publisher

Netherlands

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

Impact factor

Impact factor: 12.100 in 2022

RIV identification code

RIV/00216224:14310/23:00131284

Organization unit

Faculty of Science

UT WoS

001019046900001

Keywords in English

Ground thermal regime; Active layer thickness; Climate change; Antarctic ice-free environment; Cryosols; Gelisols; Permafrost

Tags

Tags

International impact, Reviewed
Změněno: 24/7/2023 09:03, Mgr. Marie Šípková, DiS.

Abstract

V originále

Ice-free areas occupy <0.5% of Antarctica and are unevenly distributed across the continent. Terrestrial ecosystem dynamics in ice free areas are strongly influenced by permafrost and the associated active layer. These features are the least studied component of the cryosphere in Antarctica, with sparse data from permanent study sites mainly providing information related to the ground thermal regime and active layer thickness (ALT). One of the most important results of the International Polar Year (IPY, 2007/08) was an increase in ground thermal regime monitoring sites, and consequently our knowledge of Antarctic permafrost dynamics. Now, 15 years after the IPY, we provide the first comprehensive summary of the state of permafrost across Antarctica, including the sub-Antarctic Islands, with analyses of spatial and temporal patterns of the dominant external factors (climate, lithology, biota, and hydric regime) on the ground thermal regime and active layer thickness. The mean annual ground temperatures of the active layer and uppermost part of the permafrost in Antarctica remain just below 0 °C in the warmest parts of the Antarctic Peninsula, and were below −20 °C in mountainous regions of the continent. The ALT varies between a few cm in the coldest, mountainous, parts of the Transantarctic Mountains up to >5 m in bedrock sites in the Antarctic Peninsula. The deepest and most variable ALTs (ca. 40 to >500 cm) were found in the Antarctic Peninsula, whereas the maximum ALT generally did not exceed 90 cm in Victoria Land and East Antarctica. Notably, found that the mean annual near-surface temperature follows the latitudinal gradient of −0.9 °C/deg. (R2 = 0.9) and the active layer thickness 3.7 cm/deg. (R2 = 0.64). The continuous permafrost occurs in the vast majority of the ice-free areas in Antarctica. The modelling of temperature on the top of the permafrost indicates also the permafrost presence in South Orkneys and South Georgia. The only areas where deep boreholes and geophysical surveys indicates discontinuous or sporadic permafrost are South Shetlands and Western Antarctic Peninsula.

Links

GM22-28659M, research and development project
Name: Vliv změny klimatu na dynamiku periglaciálního prostředí v oblasti Antarktického poloostrova
Investor: Czech Science Foundation
MUNI/A/1323/2022, interní kód MU
Name: Environmentální a socioekonomické změny v geografickém výzkumu
Investor: Masaryk University, Environmental and socio-economic change in geographical research