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Study tracks historic Antarctica meltdowns

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Reading the history of Antarctica’s ice sheets is helping climate scientists project the future.

Transition from glacial periods punctuated by sudden surges of ice melt and sea level rise

Staff Report

FRISCO — Even without the addition of heat-trapping greenhouse gases from fossil fuel combustion, the Antarctica ice sheets may be vulnerable to sudden collapse and melting. One such episode, about 14,600 years ago, is thought to have caused sea level to rise by more than 12 feet in just 100 years.

Scientists are racing to understand the dynamics of the Antarctic ice sheets because of the potentially significant consequences of rapid changes, and in one of the newest studies, they’ve traced some of the big iceberg calving events between about 19,000 and 9,000 years ago by analyzing deep sea sediment cores extracted from the region between the Falkland Islands and the Antarctic Peninsula. Continue reading

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Climate: Study redefines Greenland Ice Sheet topography, finds greater risk of fast melting

How fast will the Greenland Ice Sheet melt? Map courtesy Change in Elevation over Greenland ICESat's precise elevation change measurements, combined with information from other technologies, are producing a comprehensive look at the behavior of Earth’s ice sheets -- critical for quantifying forecasts of sea level rise. Scientists used ICESat data to show changes in elevation over the Greenland ice sheet between 2003 and 2006. White regions indicate a slight thickening, while the blue shades indicate a thinning of the ice sheet. Gray indicates areas where no change in elevation was measured.  Credit: NASA Goddard's Scientific Visualization Studio

How fast will the Greenland Ice Sheet melt?
Credit: NASA Goddard’s Scientific Visualization Studio.

STAFF REPORT

FRISCO — New data on Greenland’s rugged shoreline topography doesn’t bode well for coastal cities around the world. A series of deep canyons stretching for miles under the Greenland Ice Sheet will enable warming ocean water to flow beneath the ice, accelerating melting and sea level rise, according to a new study published in the journal Nature Geoscience.

The bedrock canyons sit well below sea level, meaning that as subtropical Atlantic waters hit the fronts of hundreds of glaciers, those edges will erode much further than had been assumed and release far greater amounts of water, the study found. Continue reading

Glacier inventory to help with sea level projections

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The world’s glaciers are dwindling.

CU Boulder scientists help lead mapping effort

Staff Report

FRISCO — Lots of quibbling over the exact rate and pace of glacier melt has at least partly obscured the grim reality that many of the world’s glaciated regions will see profound changes in the next few decades as global temperatures continue to rise.

That meltdown will raise sea level, but so far, nobody has been able to quantify the amount precisely. But new data gathered in a study led by University of Colorado, Boulder scientists should help. The team, including researchers from Trent University in Ontario, Canada recently completed the first mapping of virtually all of the world’s glaciers. That enables calculations of their volumes and ongoing contributions to global sea rise as the world warms. Continue reading

Is the Greenland glacier meltdown partly caused by natural climate variability?

A new study of the Greenland snowpack reached surprising conclusions about concentrations of carbon monoxide.

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

Staff Report

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

Climate: Antarctica study traces history of Pine Island Glacier melt

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How fast will Antarctica’s Pine Island Glacier melt?

Findings suggest the West Antarctica glacier is very sensitive to environmental change

By Summit Voice

FRISCO — Antarctica’s Pine Island Glacier is likely to remain a significant factor in global sea level rise for decades to come, as a warming ocean melts the ice from beneath.

Geologists from the UK, USA and Germany used highly sensitive dating techniques, pioneered by one of the team, to track the thinning of the glacier through time, and to show that past thinning has lasted for several decades.

Rocks exposed by retreating or thinning glaciers provide evidence of past ice sheet change, which helps scientists to predict possible future change. The research results were published this week in Science. Continue reading

Climate: Storm surge damage costs forecast to soar

‘If we ignore this problem, the consequences will be dramatic’

Winter storm surge eats away a beach on the west coast of Florida.

Winter storm surge eats away a beach on the west coast of Florida. bberwyn photo.

By Summit Voice

FRISCO — Watching damage from individual megastorms like Hurricane Sandy and Typhoon Haiyan is bad enough, but the outlook for coming decades is downright scary.

According to new research, global average storm surge damages could increase from about $10-$40 billion per year today to up to $100,000 billion per year by the end of century without significant adaptation measures.

“If we ignore this problem, the consequences will be dramatic,” said Jochen Hinkel, a researcher with the Berlin-based think-tank Global Climate Forum. Continue reading

Climate: Are Greenland’s glaciers speeding up?

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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

Study: New Jersey shoreline faces significant threat from rising sea level

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Was Superstorm Sandy a sign of things to come for the Jersey Shore?

Due to a combination of factors, sea level along the Atlantic Seaboard is rising much faster than the global average

By Summit Voice

FRISCO — The impacts of Hurricane Sandy may be a harbinger of future coastal devastation along the New Jersey shoreline, where sea level is rising much faster than the global average during the next century.

If the research by geoscientists at Rutgers and Tufts universities proves true, sea level in the region may rise by1.5 feet by 2050 and 3.5 feet by 2100 — that would mean that, by the middle of the century, the one-in-10 year flood level at Atlantic City would exceed any flood known there from the observational record, including Superstorm Sandy.

The study is based  in part on an analysis of  historic and modern-day records of sea-level rise in the U.S. mid-Atlantic region and builds on a recent study that reconstructed a 2,500-year record of sea level at the New Jersey shore. Continue reading

Climate: Rising sea level will drive coastal impacts

Sea level is rising, and will continue to rise for centuries even if we cut greenhouse gas emissions.

Sea level is rising, and will continue to rise for centuries even if we cut greenhouse gas emissions.

Threats will increase regardless of hurricane activity

By Summit Voice

FRISCO — Increased damage to coastal property from rising sea levels is all but certain, according to a team of top researchers who urged a holistic approach to managing coastal systems. Regardless of changes in storm activity, rising sea levels will become the dominant driver of flooding and coastal damage, their study found.

“The potential for sea-level rise to dramatically change the landscape is an understudied aspect of coastal flooding,” said Jennifer Irish, an associate professor of civil and environmental engineering with the Virginia Tech College of Engineering. “For example, shoreline erosion, barrier-island degradation, and new tidal inlet formation — these sedimentary changes could lead to catastrophic changes in hurricane flood risk in some areas,” Irish said. Continue reading

Report: IPCC sea level rise projection may be too low

Many experts think seas could rise 2 meters by 2100

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Sea level rise is already inundating parts of the Mississippi Delta. bberwyn photo.

By Summit Voice

FRISCO — Keeping sea level rise below 1 meter will require significant reductions in greenhouse gas emissions, a team of German and American researchers said this week after compiling the best available and most recent science.

Even with big cuts, sea level is expected to rise 40-60 centimeters by 2100 and 60-100 centimeters by 2300, according to the survey.

“While the results for the scenario with climate mitigation suggest a good chance of limiting future sea-level rise to one meter, the high emissions scenario would threaten the survival of some coastal cities and low-lying islands,” said Stefan Rahmstorf from the Potsdam Institute for Climate Impact Research. Continue reading

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