Global Warming

Scientists stunned to find what’s really causing Greenland’s ice loss

Scientists have achieved a tremendous breakthrough in understanding the gradual loss of the Greenland ice sheet, and they’ve determined that clouds are what’s accelerating it.

The melting of Greenland’s ice sheet is cause for great concern as climate change worries rise to the forefront. The melting of this ice sheet could cause the global sea level to rise dramatically. But the fact that clouds are likely behind this phenomenon, based on a new study, is sending some ripples through the scientific community, according to a Washington Post report.

It’s an important discovery that could allow scientists to make more accurate predictions about the melting of the Greenland ice sheet. If climate change causes more cloud cover over the ice sheet, it could accelerate the process.

Clouds can accelerate warming by trapping heat on the surface of the Earth, resulting in higher surface temperature and thus increasing the rate of melting.

The highest amount of melting actually occurs at night, when the clouds prevent temperatures from cooling as much as they normally would. The clouds also keep ice that has melted from refreezing.

Still, the subject remains somewhat controversial, as many scientists disagree on how much effect cloud cover has on Greenland’s ice sheet. There haven’t been many studies that have enough scale to truly tackle the problem.

It’s tough to conduct such research as it is hard for scientists to observe clouds by satellite, as clouds and ice look similar from the air. Infrared techniques don’t work that well either, as clouds and ice cover have a similar temperature.

However, this discovery does provide a new lead for scientists who are hoping to understand more about the effects of climate change, and create better models to predict ice loss.

Global Warming

Record Melt Occurring in Greenland Glaciers

Greenland’s glaciers are retreating under the influence of climate change at least twice as fast as any other time in the past 9,500 years, according to new research.

Scientists from Columbia University’s Earth Institute made the discovery after examining sediment cores from the bottom of a glacier-fed lake in southeastern Greenland.

They then compared the findings to analyses of similar cores from Iceland and Canada's Baffin Island, and with recent satellite observations.

They found that before the 20th century, the fastest rate of glacier retreat occurred about 8,500 years ago, when the Earth's position relative to the sun resulted in more summer sunlight warming the Arctic.

Despite less direct summer sunlight in recent years, Greenland’s glaciers have melted at an unprecedented rate because of warming brought on by higher greenhouse gas concentrations.

“If we compare the rate that these glaciers have retreated in the last hundred years to the rate that they retreated when they disappeared between 8,000 and 7,000 years ago, we see the rate of retreat in the last 100 years was about twice what it was under this naturally forced disappearance,” said study co-author William D’Andrea.

The study also provided new evidence for just how sensitive glaciers are to temperature, showing that they responded to past abrupt cooling and warming periods, some of which might have lasted only decades.

Global Warming

Huge Greenland Glacier Crumbling Into The Sea

A massive Greenland glacier holding enough ice to raise world sea levels around 18 inches is retreating from the frigid island's coastline, and its leading edge is tumbling into the North Atlantic, researchers report.

The Zachariae Isstrom Glacier has been in an accelerated retreat since 2012 and is now losing its ice at the rate of more than five billions tons a year, they say.

The glacier is now breaking up and calving high volumes of icebergs into the ocean, which will result in rising sea levels for decades to come.

Decades of progressively-rising air temperatures are melting the glacier's top, while currents of warming ocean water are compromising its underside.

Located in northeastern Greenland, the glacier has lost 95 percent of the ice shelf that previously worked to stabilize it, researchers say. Most of the reduction in Zachariae Isstrom's mass is from ice loss as the glacier calves off huge chunks of its forward end into the ocean.