The Mapping and Geographic Information Centre (MAGIC) at the British Antarctic Survey have produced new maps of the topography (physical features) and geology of Alexander Island in Antarctica.
New maps like this not only demonstrate the success of new technologies to map remote locations but are vital tools in aiding navigational and scientific endeavours in the region.
Alexander Island lies off the west coast of the Antarctic Peninsula and it is the largest island in Antarctica and the second largest uninhabited island in the world. The region surrounding Alexander Island is shown on the map, including the well-studied Wilkins and George VI ice shelves, and the smaller islands of Rothschild, Charcot and Latady.
The history of the region is a very interesting one. The island was first sighted and roughly charted in 1821, although it took until 1940 to confirm that the island was entirely disconnected from the mainland by the George VI Sound. The first detailed reconnaissance map of the region was compiled in 1959 by the Falkland Island Dependencies Survey (FIDS), the predecessor to BAS. Further maps were released in the 1980s, but none of these are comparable to modern standards of mapping. The island itself is constantly changing in this volatile polar environment, meaning new maps are needed to be made.
The topographic map contains information including the coastline and ice shelf extents, contours, mountain spot heights, rock outcrop extents, and place names. It displays the information in an easy-to-read manner.
Alexander Island has extensive mountain ranges reaching over 3000 metres in elevation. Due to the inhospitable conditions in these regions, exploration can be treacherous and very few of these mountains have been summited as a result. The team used satellite derived data to extract the heights of mountains. Mount Stephenson has long been thought the highest mountain on the island at 2944 m, but these new findings confirmed thinking in BAS that Mount Hall is the tallest at 3078 m!
Ice shelves in the region are another important feature to show accurately. The Wilkins Ice Shelf has undergone dramatic changes in recent years. Once connected to Charcot Island via ice bridge, the final remnants linking them collapsed in 2009 after years of gradual thinning. The retreat has continued since then, meaning the ice shelf remains vulnerable and is expected to recede further, much like many ice shelves along the Antarctic Peninsula. The extents displayed on the map show its position as of late 2024 and early 2025, but in some areas it will have already changed.
