NASA says a new island has emerged in Alaska in just 40 years

NASA has revealed that a new island has popped up in Alaska, and it took only about four decades to form. A typical island is created by vast tectonic plate movement over centuries, sometimes even thousands of years. It is only about a five square km piece of land and is known as Prow Knob, which was once surrounded by the deep ice of the Alsek Glacier. The space agency has released satellite images that show the new island, which experts say is a result of climate change. NASA says the small mountain is completely cut off from the mainland and has lost all contact with the Alsek Glacier. It says human action that affected the climate has led to the emergence of this new island. The images were taken by the Landsat 8 satellite in August. NASA's Earth Observatory said that this landmass turned into an island sometime between July 13 and August 6. Also Read: Scientists surprised to see organism 'alive and moving' inside Arctic Ocean that they thought was dead

Lindsey Doermann with the NASA Earth Observatory, said in a statement, "Along the coastal plain of southeastern Alaska, water is rapidly replacing ice." Earliest records of the Alsek glacier that date back to 1894 show that the Alsek Glacier once entirely covered what is today Alsek Lake. Reports from 1907 describe the glacier as being "anchored to a nunatak", a rocky region surrounded by flowing glacial ice on all sides. This nunatak was named Prow Knob since it resembled a ship's prow and was surrounded by an ice face that was about 164 feet high. This ice was visible even in the photos taken in the 1960s.

However, the warming climate has changed the conditions and caused the glacier to weaken.

Climate change triggered glacial retreat

Doermann says, "Glaciers in this area are thinning and retreating, with meltwater proglacial lakes forming off their fronts." The changes in the glacier were first noticed in 1984 when an aerial photo taken by NASA's Landsat 5 satellite revealed that the glacier's westernmost edge had turned into a lake shore. As the glacier continued to retreat, more portions of the mountain started becoming visible. The process accelerated in the 1990s, and the glacier's northerly arm cut off from a small island. This made it vulnerable to glacial calving, after which two glacial tributaries to the north and the south retreated.

The glacier was no longer getting any new ice. From 2018 to now, the glacial retreat sped up even more, and Prow Knob was soon left with water on all sides. The Alsek Lake, the Harlequin and Grand Plateau lakes have more than doubled in size in the last 40 years.