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Climate: July warmup brings quick Arctic meltdown


Arctic sea ice extent dipping near last year’s record low.

Ice melt in early July was 61 percent faster than average rate

By Summit Voice

FRISCO — After an up and down start to the Arctic ice melt season, the Arctic summer started to take its toll on sea ice in early July.

With a shift in the large-scale weather pattern bringing warm southerly winds to the region, sea ice melted at a rate of 51,000 square miles per day during the first half of the month. That’s about 61 percent faster than the average rate of decline between 1981 and 2010, according to the National Snow and Ice Data Center’s mid-month update. Continue reading

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Study tracks links between sea ice and climate

No smoking gun — yet


Large areas of open water where there historically was ice is affecting regional air temperatures and atmospheric circulation in the Arctic. Image courtesy NASA.

By Bob Berwyn

FRISCO — There’s no doubt that the continuing decline of Arctic sea ice is going to affect climate and weather across the northern hemisphere, but researchers are still trying to pinpoint exactly what the impacts will be.

In one recent study, scientists with the Cooperative Institute for Research in Environmental Science found that as sea ice disappeared, the areas of relatively warm open water began to strongly influence the atmosphere, increasing surface temperatures in the region, and shifting low- and high-pressure zones around most markedly in the fall and winter.

“The way I see it, it’s one of the wild cards out there,” said Mark Serreze, director of the National Snow and Ice Data Center. “The issue is just what those changes are going to  look like. That’s what we’re really still grappling with, we don’t have a handle on this … Is there a smoking gun? No, not yet,” Serreze said, discussing the findings of the new study. Continue reading

April 2013 ranks as 13th-warmest on record

Widespread above-average sea surface temps reported in monthly report


Despite some pockets of chilly weather, April 2013 global temps ranked as the 13th-warmest on record. Graphic courtesy NOAA/NCDC.

By Summit Voice

FRISCO — Despite a wide swath of cooler-than-average temperatures stretching from Alaska across parts of Canada and into Central North America, the average global temperature for April was well above average, ranking as the 13th-warmest April on record.

For the year to-date, global temperature across land and ocean surfaces are tied with 2009 as the eighth warmest on record, at 1.01 degrees above the 20th century average.

It also marked the 37th consecutive April and 338th consecutive month (more than 28 years) with a global temperature above the 20th century average. The last below-average April temperature was April 1976 and the last below-average temperature for any month was February 1985.

Given the absence of El Niño, global sea surface temperatures were especially notable, ranking as the seventh-warmest on record, according to the National Climatic Data Center, which this week released its monthly global climate analysis. Continue reading

Climate: Thin, first-year ice now dominates Arctic Ocean


The map at top shows the ages of ice in the Arctic at the end of March 2013; the bottom graph shows how the percentage of ice in each age group has changed from 1983 to 2013. Credit: NSIDC courtesy J. Maslanik and M. Tschudi, University of Colorado.

Seasonal shift begins in northern latitudes

By Summit Voice

FRISCO — It’s just the very start of the melt season in the Arctic, but sea ice has already dropped below last year’s level, which ended with a record low extent in September.

In the early April update, the National Snow and Ice Data Center reported that levels of multiyear ice remain extremely low. Satellite data suggests that first-year ice may now cover the North Pole area for the first time since the winter of 2008.

For March, the average extend was about 5.81 million square miles, which is about 274,000 square miles below the 1979 to 2000 average extent, and about 236,000 square miles above the record low for the month, set in 2006. March sea ice extent is declining at a rate of about 2.5 percent each decade, losing about 15,300 square miles per year, (about the size of Maryland and Delaware combined). Continue reading

New website to report on Greenland’s melting ice cap


The Greenland ice sheet is becoming less reflective, according to NASA measurements.

Portal to feature daily updates on melting episodes and analysis of conditions

By Bob Berwyn

SUMMIT COUNTY — Climate scientists have long been keeping a close watch on Greenland’s ice sheet, a key indicator of global warming impacts. This month, the National Snow and Ice Data Center launched a new website to help track the changes on an continual basis.

The new site, Greenland Today, will present images of the widespread melt on Greenland during 2012 and scientific commentary on the year’s record-breaking melt extent, which far exceeded all previous years of satellite monitoring, and led to significant amounts of ice loss for the year.

Satellite images updated daily, with a one-day lag and a daily melt image shows where the surface of the Greenland Ice Sheet experienced melt on that day.

“The Greenland melting last year was just tremendous … about 600 to 700 billion tons of ice melted and ran off,” said NSIDC glaciologist Ted Scambos, explaining that, as recently as the 1990s, scientists estimated the rate of melt at anywhere from zero to 30 billion tons. Just in the past few years, that number jumped dramatically, from 100 billion to 500 billion tons or more, Scambos said. Continue reading

Climate: Arctic sea ice near record low in December


Arctic sea ice extent in December hovered near the record low.

Significant negative trend seen in peripheral seas

By Summit Voice

FRISCO — Arctic sea ice extent stayed well below average during December, especially in the Kara, Barents, and Labrador seas. For the month, the extent was the second-lowest in the satellite record, dating back to 1979.

Sea ice extent is slightly above average on the Pacific side of the Arctic edging farther south into the Bering Sea — the only part of the Arctic that has shown a slightly positive trend in ice extent during the winter months, according to the National Snow and Ice Data Center. Continue reading

Arctic sea ice stayed near record low levels during November


Arctic sea ice grows fast in November, but the average extent is decreasing from year to year. Graph courtesy NSIDC.

Despite above-average growth, the ice sheet did not catch up to average

By Summit Voice

SUMMIT COUNTY — Even though Arctic sea ice grew at an above-average pace during November, the overall extent still remained one of the lowest on record during the satellite era, reaching 9.9 million square kilometers. Only a couple of other years have seen a lower sea ice extent at the end of November, according to the National Snow and Ice Data Center.

During November, the ice sheet grew at an average rate of 98,600 square kilometers per day. The ice extent remained below the all-time record low for most of November before just matching those record low levels at the end of the month. Continue reading

Arctic sea ice rebounds in October, but stays well below average

October Arctic sea ice has been declining at a rate of about 7.1 percent per decade during the satellite era.

Warm air temps due to open water inhibits ice growth in some areas

By Summit Voice

FRISCO — Arctic sea ice expanded quickly in October, with coverage doubling from the record low level of mid-September. But because the ice dwindled to an all-time low level this summer, even the record rebound in October couldn’t boost the ice extent back into the average range, according to the latest update from the National Snow and Ice Data Center.

The average ice extent for October was 2.7 million square miles, the second lowest in the satellite record and about 89,000 square miles above the 2007 record low for October. The ice extent is about 884,000 square miles below the 1979 to 2000 average. Continue reading

Climate: Arctic sea ice expanding, but impacts from record-low levels could still be felt the next few months

Antarctic sea ice extent remains above average

Antarctic sea ice has dwindled from a record-high extent in October but remains above average for this time of year. Bob Berwyn photo.

By Summit Voice

SUMMIT COUNTY — Although Arctic sea ice cover has grown quickly the past few weeks, the extent remained below the previous record low for a full 40 days before recently climbing back to near that 2007 level on Oct. 6.

According to the National Snow and Ice Data Center, sea ice extent had grown to about 2 million square miles as of Oct. 15, which is about 1.35 million square miles below the 1979 to 2000 mean. Ice extent is growing by about 38,600 square miles per day, expanding southward at the ice edge, as well as northward from the Arctic continental coasts

Despite the rapid growth of the sea ice extent in the past few weeks, vast areas of open water remain, resulting in a massive heat transfer from the ocean to the atmosphere, with potential impacts on atmospheric circulation in high latitudes, as the heat buildup over the Arctic changes pressure gradients in the region. Continue reading

Global Warming: Coast Guard tracks Arctic Ocean changes

New equipment deployed to help monitor impacts of melting sea ice

Open water just beyond the edge of the ice pack in Sept. 2012. Photo courtesy Ignatius Rigor.

By Summit Voice

SUMMIT COUNTY — For better or worse, the Arctic is changing fast, and even if greenhouse gas emissions dropped to zero tomorrow, those changes are likely to continue for decades, and perhaps centuries.

In response to the changes, the U.S. Coast Guard and the University of Washington are partnering to get more data on the region, starting by deploying sensors and other equipment through cracks in the ice from an airplane hundreds of feet in the air.

This year saw record ice melt, and some scientists speculate that the Arctic ocean could be entirely ice free in summer during the next few decades.

“It used to be that the ice just pulled back a bit from the beach each year,” said Jamie Morison, an oceanographer at the UW’s Applied Physics Laboratory. “Now we’re seeing huge areas of open water.” Continue reading


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