Tag: Greenland ice sheet

Greenland ice sheet meltdown not affecting Gulf Stream – yet

A pool of icy water twice the size of Lake Victoria could disrupt the Gulf Stream when it pours out of the Arctic Ocean into the Atlantic.
A pool of icy water twice the size of Lake Victoria could disrupt the Gulf Stream when it pours out of the Arctic Ocean into the Atlantic.

New study says impacts expected to show up in 20-30 years

Staff Report

Ocean researchers tracking currents in the North Atlantic say that, so far, the massive amounts of freshwater, pouring off the melting Greenland Ice Sheet haven’t yet had a major effect on the Gulf Stream.

That influx of fresh water has increased by 50 percent since 1990 from both enhanced summer melt and calving outlet glaciers that are adding about 5,000 cubic kilometers of water per year — equivalent to a quarter of the volume of the Baltic Sea. Continue reading “Greenland ice sheet meltdown not affecting Gulf Stream – yet”

Connecting the climate change dots

Peak 1 alpenglow
Global warming is going to push the snow line uphill by as much as 1,400 feet in many western mountains. @bberwyn photo.

Pole to pole and across the world’s oceans and mountains, climate change impacts are adding up

By Bob Berwyn

For any Summit Voice readers not following my Twitter or Facebook feeds, here’s a list of links to my recent stories for InsideClimate News.

Of greatest interest here in the West is a new University of Utah study that projects a dramatic upward shift of the snowline in the Rockies and coastal ranges in California, Oregon and Washington. Less spring snowpack at lower elevations has huge effects on we manage our water, and could also result in more early season wildfires: Unabated Global Warming Threatens West’s Snowpack, Water Supply.

In mid-May I wrote about the latest update to NOAA’s annual greenhouse gas index, which showed that atmospheric CO2 concentration showed its biggest annual increase on record in the past year. The index also showed a surge in Methane, an etremely potent heat-trapping pollutant: Far From Turning a Corner, Global CO2 Emissions Still Accelerating. Continue reading “Connecting the climate change dots”

More evidence that melting Arctic ice drives widespread changes in northern hemisphere weather patterns

‘Blocking highs’ becoming more common over Greenland

greenland aerial view
What happens in Greenland doesn’t stay in Greenland. Climate shifts in the Arctic affect the rest of the northern hemisphere. @bberwyn photo.

Staff Report

Just a few weeks after scientists reported record early melting on parts of the Greenland Ice Sheet, a new study helps explain some of the recent dramatic climate shifts in the high latitudes of the northern hemisphere.

Stationary high pressure systems over Greenland have become more frequent since the 1980s, said University of Sheffield geographer Prof. Edward Hanna, adding that the pattern is also linked with extreme weather over northwest Europe, including unusually wet conditions in the UK in the summers of 2007 and 2012.

The study, published in the International Journal of Climatology, looked at large-scale weather patterns over Greenland going back to 1851 using a measure called the Greenland Blocking Index, which marks the how strong the high pressure systems are, how long they last and how often they occur. Continue reading “More evidence that melting Arctic ice drives widespread changes in northern hemisphere weather patterns”

Climate: Jet stream shifts may speed Greenland meltdown

More sea level woes ahead?

Melting on the surface of the Greenland Ice Sheet.
Melting on the surface of the Greenland Ice Sheet. @bberwyn photo.
How will global warming affect the flow of the jet stream?
How will global warming affect the flow of the jet stream?

Staff Report

Scientists are tracking yet another global warming feedback mechanism that will have dire consequences for coastal communities around the world. Melting sea ice and overall rapid warming in the Arctic are factors in the development of so-called blocking high pressure systems — air masses spinning clockwise that block cold, dry Canadian air from reaching Greenland.

The highs tend to enhance the flow of warm, moist air over Greenland, contributing to increased extreme heat events and surface ice melting, according to the study. That circulation pattern leads to more melting of the Greenland Ice Sheet, according to new research published online in the Journal of Climate last month, co-authored by Jennifer Francis, one of the pioneers in studying how global warming is affecting the jet stream. Continue reading “Climate: Jet stream shifts may speed Greenland meltdown”

Greenland meltdown threatens key Atlantic Ocean current

Sea ice swirls around Greenland in this NASA Earth Observatory photo.

‘If human activities are starting to impact this system, it is a worrying sign that the scale of human impacts on the climate system may be reaching a critical point’

Staff Report

Cold, fresh water from the Greenland Ice Sheet may disrupt a key ocean current in the North Atlantic, scientists said after updating estimates of the freshwater flux based on new satellite data. The study, published in the journal Nature Communications, warns that the changes could have as-yet uncertain implications for the global climate.

At issue is the Atlantic Meridional Overturning Circulation, which transports a large amount of heat into the North Atlantic where it is given up to the atmosphere and helps regulate the climate in Europe and North America. Continue reading “Greenland meltdown threatens key Atlantic Ocean current”

Climate: One more thing to worry about?

Ongoing studies are detailing how melting ice sheets will affect sea level.

Eastern Greenland changes could threaten critical ocean current

By Bob Berwyn

The global climate agreement reached late last year in Paris isn’t going to stop the Greenland Ice Sheet from melting anytime soon. Even with an immediate halt to greenhouse gas emissions. there may be centuries more melting ahead, according to climate scientists.

And the meltdown could be more widespread than previously thought, according to National Snow and Ice Data Center scientist Lora Koenig, who gave an update on the latest research during this week’s Glen Gerberg Weather and Climate Summit in Breckenridge. Continue reading “Climate: One more thing to worry about?”

Climate: Extreme Greenland Ice Sheet melting episodes change runoff regime

Extreme melting on the surface of the Greenland ice sheet could change the sea level rise equation.

Study shows that 2012 melting created a dense ice cap

Staff Report

When warm temperatures in 2012 caused an extreme melting episode across much of the Greenland Ice Sheet, it may have fundamentally altered the way the near-surface snow layers absorb water, according to a new study published in Nature Climate Change.

The melting resulted in the formation of a thick layer of ice atop the previously porous surface. Subsequently, meltwater ran off the surface and to the ocean, with potential impacts on sea level, according to York University Professor William Colgan. Continue reading “Climate: Extreme Greenland Ice Sheet melting episodes change runoff regime”