RT info:eu-repo/semantics/article
T1 Recent shallowing of the thaw depth at Crater Lake, Deception Island, Antarctica (2006-2014)
A1 Ramos Sainz, Miguel
A1 Pablo Hernández, Miguel Ángel de
A1 Vieira, G
A1 Molina, Antonio
A1 Abramov, Andrei
A1 Goyanes, Gabriel
K1 Permafrost
K1 Decreasing thaw depth
K1 Active layer
K1 Snow insulation
K1 Antarctic peninsula
K1 Física
K1 Physics
AB The Western Antarctic Peninsula region is one of the hot spots of climate change and one of the most ecologically sensitive regions of Antarctica, where permafrost is near its climatic limits. The research was conducted in Deception Island, an active stratovolcano in the South Shetlands archipelago off the northern tip of the Antarctic Peninsula. The climate is polar oceanic, with high precipitation and mean annual air temperatures (MAAT) close to -3°C. The soils are composed by ashes and pyroclasts with high porosity and high water content, with ice-rich permafrost at -0.8°C at the depth of zero annual amplitude, with an active layer of about 30 cm. Results from thaw depth, ground temperature and snow cover monitoring at the Crater Lake CALM-S site over the period 2006 to 2014 are analyzed. Thaw depth (TD) was measured by mechanical probing once per year in the end of January or early February in a 100 × 100 m with a 10 m spacing grid. The results show a trend for decreasing thaw depth from ci. 36 cm in 2006 to 23 cm in 2014, while MAAT, as well as ground temperatures at the base of the active layer, remained stable. However, the duration of the snow cover at the CALM-S site, measured through the Snow Pack Factor (SF) showed an increase from 2006 to 2014, especially with longer lasting snow cover in the spring and early summer. The negative correlation between SF and the thaw depth supports the significance of the influence of the increasing snow cover in thaw depth, even with no trend in the MAAT. The lack of observed ground cooling in the base of the active layer is probably linked to the high ice/water content at the transient layer. The pyroclastic soils of Deception Island, with high porosity, are key to the shallow active layer depths, when compared to other sites in the Western Antarctic Peninsula (WAP).
PB Elsevier
SN 0341-8162
YR 2017
FD 2017-02
LK http://hdl.handle.net/10017/33241
UL http://hdl.handle.net/10017/33241
LA eng
NO Ministerio de Economía y Competitividad
DS MINDS@UW
RD 25-abr-2024