Posted on March 25, 2015 by Bob Berwyn
Influx of cold, fresher water could tip climate scale
FRISCO — Earth scientists have long speculated that a massive infusion of cold and relatively fresh water into the North Atlantic could disrupt a key climate-regulating ocean current, with huge consequences for adjacent land areas.
New measurements of ocean temperatures in the region, along with other climate data, now suggest that the Atlantic Overturning Current has already slowed quite a bit in the past 100 years, and especially since 1970. The current, which is related to the Gulf Stream, helps moderate temperatures in northwestern Europe and northeastern North America.
Further weakening of the current could impact marine ecosystems and sea level as well as weather systems in the US and Europe, scientists say in a new study to be published in Nature Climate Change. Continue reading
Filed under: climate and weather, climate change, global warming, Greenland | Tagged: Atlantic overturning current, global warming, greenland, Gulf Stream | Leave a comment »
Posted on May 8, 2014 by Bob Berwyn
Warming temps around Greenland may be partly due to natural climate variability.
New study shows link between Pacific Ocean hotspot and North Atlantic weather patterns
FRISCO — Climate researchers and glaciologists have long been tracking the meltdown of Greenland’s glaciers. The region has been warming at the astounding rate of about 1 degree Celsius per decade — several times the global average — but part of that may be due to natural variability, according to a new study led by University of Washington scientists.
The research suggests up to half the recent warming in the area may be linked with climate patterns born in the tropical western Pacific rather than with the overall warming of the planet. Continue reading
Filed under: Arctic, climate and weather, global warming, Greenland | Tagged: Arctic, climate change, Environment, global warming, greenland, sea level rise | 1 Comment »
Posted on April 21, 2014 by Bob Berwyn
A new study of Greenland ice cores suggests parts of the ice sheet persisted through previous global warming spells.
Will there be a meltdown?
FRISCO — At least some parts of the Greenland ice sheet likely survived some of the warmest interludes in the Earth’s geologic climate history, researchers said last week as they announced findings of a study that discovered an ancient tundra landscape preserved under the Greenland Ice Sheet, below two miles of ice.
“We found organic soil that has been frozen to the bottom of the ice sheet for 2.7 million years,” said University of Vermont geologist and lead author Paul Bierman. The finding provides strong evidence that the Greenland Ice Sheet has persisted much longer than previously known, enduring through many past periods of global warming. Continue reading
Filed under: climate and weather, global warming, Greenland | Tagged: climate, climate change, global warming, greenland, Greenland ice sheet | 1 Comment »
Posted on February 4, 2014 by Bob Berwyn
New data shows at least one glacier moving at a record pace of 50 feet per day
By Summit Voice
FRISCO — Arctic ice researchers say detailed measurements show that one Greenland’s glaciers has been moving at a record speed the past few years.
The scientists with the University of Washington and the German Space Agency measured the movement of the Jakobshavn Isbræ (Jakobshavn Glacier) in 2012 and 2013, concluding that the glacier is moving four times as fast as during the 1990s.
“We are now seeing summer speeds more than 4 times what they were in the 1990s on a glacier which at that time was believed to be one of the fastest, if not the fastest, glacier in Greenland,” said Ian Joughin, a researcher at the Polar Science Center, University of Washington and lead-author of the study. Continue reading
Filed under: climate and weather, Environment, global warming | Tagged: climate change impacts, glaciers, global warming, greenland, sea level rise | Leave a comment »
Posted on October 25, 2013 by Bob Berwyn
‘The warming we are seeing is outside any kind of known natural variability, and it has to be due to increased greenhouse gases in the atmosphere …’
Baffin Island‘s ice caps are melting fast under an unprecedented regime of global warming, according to a new CU-Boulder study: Photo courtesy NASA.
By Summit Voice
FRISCO — After radiocarbon dating samples of moss at the edge of melting ice caps on Baffin Island, scientists said there’s little doubt that current warming in the Arctic is unprecedented, even on a geological time scale.
Average summer temperatures in the Eastern Canadian Arctic during the last 100 years are higher than during any century in the past 44,000 years and perhaps as long ago as 120,000 years, according to a University of Colorado Boulder study.
“The key piece here is just how unprecedented the warming of Arctic Canada is,” said CU-Boulder geologist Gifford Miller, also a fellow at CU-Boulder’s Institute of Arctic and Alpine Research. “This study really says the warming we are seeing is outside any kind of known natural variability, and it has to be due to increased greenhouse gases in the atmosphere.” Continue reading
Filed under: climate and weather, Environment, global warming, Greenland | Tagged: Arctic, Baffin Island, climate change, global warming, greenland, Little Ice Age | 1 Comment »
Posted on October 2, 2013 by Bob Berwyn
Caribour browsing in Alaska. Photo courtesy USGS.
Melting sea ice leads to trophic mismatch
By Summit Voice
FRISCO — As scientists amass more long-term observational data on global warming impacts in the Arctic, it’s becoming increasingly clear that melting sea ice will affect nearby land areas. In one of the most recent studies, Penn State researchers concluded that melting sea ice may be related to fewer caribou calf births and higher calf mortality in Greenland.
As the sea ice melts, warmer air temperatures in the surrounding area are causing plants to start growing earlier. But because caribou aren’t breeding any earlier, the calving season is out of synch with food availability, according to Eric Post, a Penn State University professor of biology, and Jeffrey Kerby, a Penn State graduate student. Continue reading
Filed under: biodiversity, climate and weather, Environment, global warming, wildlife | Tagged: caribou, climate change impacts, global warming, greenland, phenology, trophic mismatch | Leave a comment »
Posted on September 20, 2013 by Bob Berwyn
A polar bear in the Arctic. PHOTO COURTESY USGS/SUSANNE MILLER.
Changing sea ice means shifting diet for top Arctic predators
By Summit Voice
FRISCO — The decline of Arctic sea ice is a huge threat to animals in the region, including polar bears and seals, and researchers are trying to learn how those changes will play out in the long run.
Even along the east coast of Greenland, where the sea ice may persist after it has vanished from other areas, the annual 1 percent decline in ice is affecting polar bears, according to an international team of researchers who studied polar bear diets.
After analyzing fatty tissues from 310 polar bears hunted by Greenland natives between 1984 and 2011, the scientists were able to detect subtle shifts in in their diet. Instead of relying primarily on ringed seals, residents of the high Arctic, the bears are increasingly eating subarctic harp and hooded seals. Continue reading
Filed under: Arctic, biodiversity, climate and weather, Environment, global warming, Greenland | Tagged: Arctic sea ice, global waming, greenland, Persistent organic pollutants, polar bears | Leave a comment »