Scientists studying the bottom of the world's biggest ice sheet in East Antarctica have uncovered a city-sized lake whose sediments may hold information about the ice sheet's origins.
This would provide answers to concerns about what Antarctica used to be before it froze, how climate change has influenced it through time, and how the ice sheet may act as the planet warms.
Lake Snow Eagle, revealed by fully instrumented polar research planes, is covered by 2 miles of ice and sits in a mile-deep canyon in the highlands of Antarctica's Princess Elizabeth Land, a few hundred kilometers from the coast.
Using radar for surveys
Mario Tama/Getty Images
Because it is so near to the shore, experts believe Lake Snow Eagle may have knowledge on how the East Antarctic Ice Sheet formed and the role of the Antarctic Circumpolar Current, a ring of icy water that circles the continent and is thought to be responsible for keeping it cool.
Scientists discovered the lake and its host canyon after seeing a smooth dip on satellite photos of the ice sheet.
Researchers spent several years flying methodical assessments over the location using ice penetrating radar and sensors that monitor minute adjustments in the Earth's gravity and magnetic field to establish its presence.
Shuai Yan, a doctoral student at UT Austin's Jackson School of Geosciences who was the flight planner for the field research that studied the lake, remarked, "I literally jumped when I first saw that brilliant radar reflection," as per Phys.org.
Yan saw the lake's water, which, unlike ice, reflects radar like a mirror. Yan created a precise image of a rugged, highland landscape with Lake Snow Eagle perched at the base of a canyon using gravity and magnetic surveys, which illuminated the region's underlying geology and the water depth and sediments.
The recently discovered lake has a depth of 650 feet, a length of 30 miles, and a width of 9 miles.
The sediments at the lake's bottom are roughly 1,000 feet deep and may be river sediments older than the ice sheet itself, as per AZO Cleantech.
The scientists suggested that collecting a sample of the lake's sediments by drilling into it will cover large gaps in academics' understanding of Antarctica's glaciation and provide critical data on the ice sheet's likely death due to climate change in the coming days.
Magnetic fields envelop magnetic materials and electric currents, and their effect on other magnetic materials and moving electric charges detects them.
At a given place, the magnetic field is characterized by both a direction and a magnitude (or intensity); hence, it is a vector field.
The electric and magnetic fields are two interconnected characteristics of a single phenomenon termed the electromagnetic field in special relativity.
In a moving reference frame, a pure electric field is viewed as a mixture of an electric field and a magnetic field.
Ice sheets
An ice sheet is a mass of glacial ice larger than 50,000 km2 (20,000 mile2) that covers surrounding ground.
The only active ice sheets are in Antarctica and Greenland; during the previous glacial epoch, the Laurentide ice sheet encompassed much more of Canada and North America, the Weichselian ice sheet covered northern Europe, and the Patagonian Ice Sheet covered southern South America.
Ice sheets are far larger than ice shelves or glaciers. An ice cap is a mass of ice that covers less than 50,000 km2. An ice cap will often feed a ring of glaciers surrounding it.
Although the surface of an ice sheet is chilly, the base is often hotter due to geothermal energy.
