Posted on October 29, 2015 by Bob Berwyn
All eyes on the Greenland Ice Sheet, as global warming speeds up. @bberwyn photo.
New research shows looks specifically at glaciers ending on land
Parts of the Greenland Ice Sheet may actually be slowing down, rather than speeding up, in response to decades of climate change, but that doesn’t mean it’s time to stop worrying about sea level rise.
In a new study, glaciologists measuring ice movement on the southwest portion of the Greenland Ice Sheet found that glaciers terminating on land have slowed by an average of 12 percent across 84 percent of the study area between 2007 and 2014, compared to the years between 1985 and 1994. The study looked specifically at ice sheets terminating on land, not those flowing into the ocean.
The scientists said their findings appear to contradict conventional wisdom. Many recent studies have suggested that more surface melting will speed up ice sheet movement. The amount of meltwater draining from the ice sheet in four out of the five years between 2007 and 2012 has been the most substantial of the last 50 years. Continue reading
Filed under: climate and weather, Environment, global warming, Greenland | Tagged: climate change, global warming, Greenland ice sheet, sea level rise | 1 Comment »
Posted on July 17, 2015 by Bob Berwyn
Greenland temperatures fell from the 1970s through the early 1990s while temperatures across much of the rest of the Northern Hemisphere rose, and solar activity may be an important factor.
Credit: Takuro Kobashi
Low solar activity could speed Greenland Ice Sheet melting in coming years
FRISCO — Solar activity could be an important factor in determining how fast the Greenland Ice Sheet melts, scientists concluded in a new study after analyzing ice cores and historical temperature records.
Based on their analysis, the researchers found that High solar activity starting in the 1950s and continuing through the 1980s played a role in slowing down ocean circulation between the South Atlantic and the North Atlantic oceans. Continue reading
Filed under: Arctic, climate and weather, global warming, Greenland | Tagged: AMOC, Atlantic meridional overturning circulation, climate change, global warming, Greenland ice sheet | Leave a comment »
Posted on January 22, 2015 by Bob Berwyn
A meltwater lake on the surface of the Greenland Ice Sheet. Now researchers are tracking where that water goes, and how it may affect ice sheet movement. Photo courtesy Thomas Nylen, National Science Foundation.
Surface meltwater feeds subglacial lakes
FRISCO — Scientists who recently took a close look at the “plumbing” of the Greenland Ice Sheet say that meltwater from the surface is building up lakes beneath the ice and transporting heat to the bottom of the ice sheet.
The research, led by Cornell University Earth and Atmospheric Sciences researcher Michael Willis, includes groundbreaking findings that give new information about atmospheric warming and its affect on the critical zone at the base of the ice. The warmth provided by the water could make the ice sheet move faster and alter how it responds to the changing climate. The research is detailed in a new paper published online by the journal Nature on Jan. 21. Continue reading
Filed under: Arctic, climate and weather, global warming, Greenland | Tagged: climate change, Environment, global warming, Greenland ice sheet, sea level rise | Leave a comment »
Posted on January 13, 2015 by Bob Berwyn
Massive flows contribute to sea level rise
How fast will the Greenland Ice Sheet melt?
Credit: NASA Goddard’s Scientific Visualization Studio.
FRISCO — After criss-crossing the Greenland Ice Sheet with a helicopter and deploying a remote-operated boat, a team of UCLA-led scientists say they’ve mapped an intricate network of rivers and streams flowing on top of the ice sheet.
The water from those rivulets and rivers could be responsible for as much, if not more, sea-level rise that the ice sheet’s ephemeral lakes and the monster chunks of ice that slide into the ocean to become icebergs. Continue reading
Filed under: Arctic, climate and weather, global warming, Greenland | Tagged: climate change, global warming, Greenland ice sheet, Greenland snowmelt rivers, sea level rise, UCLA | Leave a comment »
Posted on December 15, 2014 by Bob Berwyn
How fast will the Greenland ice sheet melt?
243 gigatons of ice per year …
FRISCO — The most detailed look yet at the dynamics of the Greenland ice sheet suggests that current climate models may not be capturing the full extent of melting.
A team of scientists tracking the behavior of the ice sheet said they found unexpected shrinking in southeastern Greenland, and other signs suggesting that current models may underestimate ice loss in the near future. Continue reading
Filed under: Arctic, climate and weather, climate change, global warming, Greenland | Tagged: climate change, global warming, Greenland ice sheet, sea level rise | Leave a comment »
Posted on October 15, 2014 by Bob Berwyn
Denmark-based research team seeks to pinpoint ice sheet melt factor
Large parts of the U.S. Gulf Coast could be swamped by rising seas.
Coastal tidal flooding is already causing transportation problems near Venice, Louisiana, USA. bberwyn photo
FRISCO — Developing accurate projections for sea level rise has been an elusive, high-priority goal for climate scientists. It’s certain that sea level will keep rising for centuries to come. But it’s not clear at what rate and pace that will happen, especially during the next few decades as coastal communities try to prepare.
Some factors, like thermal ocean expansion, can be established with some accuracy but researchers still aren’t sure exactly how the Greenland and Antarctic ice sheets will respond to warming.
In the latest number-crunching, scientists with the Niels Bohr Institute established that there’s little chance sea level will rise more than 1.8 meters (about 6 feet) by 2100. The results are published in the scientific journal Environmental Research Letters. Continue reading
Filed under: climate and weather, global warming | Tagged: climate, Environment, global sea level rise, Greenland ice sheet, IPCC, West Antarctic Ice Sheet | 1 Comment »
Posted on October 2, 2014 by Bob Berwyn
How fast will the Greenland Ice Sheet melt? Credit: NASA Goddard’s Scientific Visualization Studio.
New study probes role of subglacial runoff channels
FRISCO — Scientists continue to probe and poke at the Greenland Ice Sheet to try and figure out exactly how fast it will melt as global temperatures rise. In one of the newest studies, an international team drilled boreholes to measure melt rates and ice movements, finding that the story is even more complicated than we thought.
“Although the Greenland Ice Sheet initially speeds up each summer in its slow-motion race to the sea, the network of meltwater channels beneath the sheet is not necessarily forming the slushy racetrack that had been previously considered,” said Matthew Hoffman, a Los Alamos National Laboratory scientist on the project, which clarifies the evolution of the meltwater flow rates over the seasons. Continue reading
Filed under: climate and weather, global warming, Greenland | Tagged: climate change, global warming, Greenland ice sheet, sea level rise | 1 Comment »