New York: The disappearance of Arctic Sea ice due to massive climate change is causing the surface of Greenland’s melt area to increase, thereby fuelling a steep rise in the sea-level, finds a study.
During summers, melting Arctic Sea ice favours stronger and more frequent “blocking-high” pressure systems.
The high pressure tends to enhance the flow of warm, moist air over Greenland, contributing to an increased extreme heat events and surface ice melting, which in turn fuels sea-level rise, a monstrous issue for coastal communities around the world.
“Whenever there’s a big melt year in Greenland, on the surface anyway, it’s usually because there’s either a blocking high or a large northward swing in the jet stream and both of those things tend to be long-lived features in the circulation,” said one of the researchers, Jennifer Francis, professor at Rutgers University in New Jersey, US.
Both transport a lot of heat, moisture and clouds over the Greenland ice sheet, leading to more melting, the researchers pointed out.
The study was published online in the Journal of Climate.
The Greenland ice sheet holds an enormous volume of frozen water, and the global sea level would rise about 20 to 23 feet if it all melted. Surface melting of the ice sheet has increased dramatically since the relative stability and modest snow accumulation in the 1970s, the study said.
Sea-level rise is already “becoming very conspicuous and it’s going to be bad. It’s happening faster and faster,” Francis said adding that the change is accelerating.