Greenland’s massive ice sheet, which covers close to 80 percent of its surface, is believed to be the greatest portion of melting ice on the planet. For that reason, it is claimed to be the biggest probable contributor to growing sea levels as a result of glacial melting in a continuously warming world.
Scientists have dedicated their efforts into studying the aquamarine lakes found in Greenland, which are formed as a result of the melt-water, and icebergs – the massive blocks of ice that detach from the ice sheet and slide into the ocean.
A new study published in the latest issue of Proceedings of the National Academy of Sciences proves the existence of a vast network system of rivers and streams. Scientists claim that these could be greatly responsible for even more sea-level growth as the other two causes. The team observed that in the warm season, when the ice is defrosting, the rivers and streams form a complex sewerage system that is able of collecting all tributaries and spill its entire volume in two days, at most.
Laurence C. Smith, the study’s lead author, compared the drainage structure found in Greenland with “the world’s biggest water-park” that has stunning, yet deadly, rapid clear blue rivers that can cut canyons in the ice.
The research, conducted by a team of researchers from UCLA, focuses on warning about the delicacy of the ice sheet covering Greenland and tries to foresee what calamities it might create in the context of global warming.
The scientific team has tried to understand how much of the melt-water would be captured, and how much would be carried into the ocean. Also, they tried to determine how this process would happen and at what pace. The study proved successful, as the team could answer a bit of both.
The researchers compared the surface of the sheet of ice with Swiss cheese. Across a 2,000-square-mile area of ice, over 500 active rivers and streams drained in moulins, moving the melt-water into the ocean through under the ice sheet. Also, the team discovered, somewhere below the surface, an effect they described as a sponge took place: at the base of the ice sheet the drainage occurs at a rate between 55,000 and 61,000 cubic feet per second – more than double of the flow of Colorado River.
The newly published research will enable future researchers to create more accurate climate models. The existent models seem to overestimate the contribution of runoff to the riding sea level.
Image Source: Climate Croks