Climate Changes in Greenland

This page gives links to articles about changes to the climate in Greenland.

A first-ever study of air trapped in the deep snowpack of Greenland shows that atmospheric levels of carbon monoxide (CO) in the 1950s were actually slightly higher than what we have today. This is a surprise because current computer models predict much higher CO concentrations over Greenland today than in 1950. Now it appears the opposite is in fact true.

The Greenland ice sheet is melting from below, caused by a high heat flow from the mantle into the lithosphere. This influence is very variable spatially and has its origin in an exceptionally thin lithosphere. Consequently, there is an increased heat flow from the mantle and a complex interplay between this geothermal heating and the Greenland ice sheet. The international research initiative IceGeoHeat led by the GFZ German Research Centre for Geosciences establishes in the current online issue of Nature Geoscience that this effect cannot be neglected when modeling the ice sheet as part of a climate study.

While low, thin cloud cover is just one element within a complex interaction of wind speed, turbulence and humidity, the extra heat energy trapped close to the surface can push temperatures above freezing.

In the period between 130,000 and 115,000 years ago, Earth's climate was warmer than today. But how much warmer was it and what did the warming do to global sea levels? -- as we face global warming in the future, the answer to these questions is becoming very important. New research from the NEEM ice core drilling project in Greenland shows that the period was warmer than previously thought. The international research project is led by researchers from the Niels Bohr Institute and the very important results are published in the scientific journal, Nature.

Future sea level rise due to the melting of the Greenland and Antarctic ice sheets could be substantially larger than estimated in Climate Change 2007, the Fourth Assessment Report of the IPCC, according to new research from the University of Bristol.

Research has shown a decrease in levels of the isotope nitrogen-15 in core samples from Greenland ice starting around the time of the Industrial Revolution. The decrease has been attributed to a corresponding increase in nitrates associated with the burning of fossil fuels.
However, new University of Washington research suggests that the decline in nitrogen-15 is more directly related to increased acidity in the atmosphere.

Scientists have discovered what they think may be another reason why Greenland‘s ice is melting: a thin spot in Earth’s crust is enabling underground magma to heat the ice.

They have found at least one “hotspot” in the northeast corner of Greenland — just below a site where an ice stream was recently discovered.

Every year as the Greenland Ice Sheet melts, the rocky coast rises, explained Michael Bevis, Ohio Eminent Scholar in Geodynamics and professor in the School of Earth Sciences at Ohio State University. Some GPS stations around Greenland routinely detect uplift of 15 mm (0.59 inches) or more, year after year. But a temperature spike in 2010 lifted the bedrock a detectably higher amount over a short five-month period — as high as 20 mm (0.79 inches) in some locations.

A chance discovery of 80-year-old photo plates in a Danish basement is providing new insight into how Greenland glaciers are melting today.

The Greenland ice sheet continues to lose mass and thus contributes at about 0.7 millimeters per year to the currently observed sea level change of about 3 mm per year. This trend increases each year by a further 0.07 millimeters per year. The pattern and temporal nature of loss is complex. The mass loss is largest in southwest and northwest Greenland; the respective contributions of melting, iceberg calving and fluctuations in snow accumulation differing considerably.

Ice loss in Antarctica increased by 75 percent in the last 10 years due to a speed-up in the flow of its glaciers and is now nearly as great as that observed in Greenland, according to a new, comprehensive study by NASA and university scientists.

"This past melt season was exceptional, with melting in some areas stretching up to 50 days longer than average," said Dr. Marco Tedesco, director of the Cryospheric Processes Laboratory at The City College of New York (CCNY -- CUNY), who is leading a project studying variables that affect ice sheet melting.

Ice samples pulled from nearly a mile below the surface of Greenland glaciers have long served as a historical thermometer, adding temperature data to studies of the local conditions up to the Northern Hemisphere's climate.
But the method -- comparing the ratio of oxygen isotopes buried as snow fell over millennia -- may not be such a straightforward indicator of air temperature.

An ice island twice the size of Manhattan has broken off from Greenland's Petermann Glacier, according to researchers at the University of Delaware and the Canadian Ice Service. The Petermann Glacier is one of the two largest glaciers left in Greenland connecting the great Greenland ice sheet with the ocean via a floating ice shelf.

For several days this month, Greenland's surface ice cover melted over a larger area than at any time in more than 30 years of satellite observations. Nearly the entire ice cover of Greenland, from its thin, low-lying coastal edges to its two-mile-thick center, experienced some degree of melting at its surface, according to measurements from three independent satellites analyzed by NASA and university scientists.

Despite the current and rapid melting of the Greenland Ice Sheet, it remains far from certain just when we will have reached a point when scientists will be able to predict its disappearance. Recent research conducted by the University of Copenhagen in conjunction with the Technical University of Denmark (DTU) and the Danish National Survey and Cadastre (KMS) in collaboration with an international team of scientists reports that this is not the first time in recent history that the ice sheet has been in retreat and then stabilised again.

Professor Tedesco noted that these changes jibe with what most of the models predict -- the difference is how quickly this seems to be happening.