Sif Island
75°05′55″S 102°49′05″W / 75.098611°S 102.818056°W / -75.098611; -102.818056
![Sif Island is located in Antarctica](http://upload.wikimedia.org/wikipedia/commons/thumb/c/c7/Antarctica_location_map.svg/260px-Antarctica_location_map.svg.png)
![Sif Island](http://upload.wikimedia.org/wikipedia/commons/thumb/0/0c/Red_pog.svg/8px-Red_pog.svg.png)
Sif Island is an island in Pine Island Bay of the Amundsen Sea, in Antarctica. It is 1,150 feet (350 m) long and consists of potassium feldspar granite, mostly covered in ice. It was discovered in February 2020 after the Pine Island Glacier melted away from around it, and is named after Sif, an Æsir goddess associated with the Earth in Norse mythology. It is plausible that the island emerged as a result of post-glacial rebound, a process in which retreating glaciers relieve pressure on the ground, causing it to rise.[1][2]
History
The steady retreat of the Pine Island Glacier and Thwaites Glacier since the early 2010s had left Sif Island separate from glacier ice in the Pine Island Bay, completely detaching in 2014 as seen in Landsat satellite imagery. The island may now be undergoing post-glacial rebound.[1][2][3]
Sif Island was discovered in February 2020 by researchers with the Thwaites Glacier Offshore Research (THOR) project,[1] aboard the Nathaniel B. Palmer research vessel.[2] On February 11, 2020, marine geologist and crew member Julia Wellner announced the island's discovery via Twitter, stating that a crew member aboard the ship had spotted the rocky outcropping of granite, visible beneath a 'mushroom' of remnant ice.[4][5] As ships rarely pass as far south as Sif Island, it is likely that the researchers aboard the Nathaniel B. Palmer are the first people to have seen the island and landed upon its granite bedrock. Despite the island being visible by satellite, its icy cap prevented it from being discovered earlier, as it blended in with the surrounding glacier.[2]
On February 23, photos of the researchers' first landing on the island were posted by Wellner on her Twitter account. She confirmed that the island is made of granite, covered with residual ice, and home to a few seals.[4][6]
References
- ^ a b c Specktor, Brandon (February 28, 2020). "Melting ice in Antarctica reveals new uncharted island". Live Science. Archived from the original on February 29, 2020. Retrieved March 1, 2020.
- ^ a b c d Giuliana, Viglione (February 21, 2020). "New Antarctic island spotted as mammoth glacier retreats". Nature. 578 (501): 501. Bibcode:2020Natur.578..501V. doi:10.1038/d41586-020-00489-4. PMID 32099127.
- ^ ""Antarctica's Newest Ialand". United States Geological Survey. March 24, 2021. Retrieved August 10, 2021.
- ^ a b Tassart, Anne-Sophie (March 3, 2020). "Des scientifiques découvrent par hasard une nouvelle île en Antarctique" [Scientists accidentally discover a new island in Antarctica]. Sciences et Avenir (in French). Archived from the original on March 4, 2020. Retrieved March 22, 2020.
- ^ Julia Smith Wellner [@houston_wellner] (February 11, 2020). "A mate on the bridge spotted some rocky coastline this morning. This island is on no charts we know of! We look forward to visiting by Zodiac and sampling the rocks tomorrow and are pondering names for this new bit of land" (Tweet). Retrieved March 22, 2020 – via Twitter.
- ^ Julia Smith Wellner [@houston_wellner] (February 23, 2020). "After being the first visitors, we can now confirm that Sif Island is made of granite and that it is covered by remnant ice shelf, and a few seals. Photos by CD Hillenbrand (BAS) and Laura Taylor (UH)" (Tweet). Retrieved March 22, 2020 – via Twitter.