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Antarctica’s ice-free fringe needs more protection

Invasive species a huge threat to sparse ecosystems, scientists report

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Tourists on Dundee Island hike past birds and pinnipeds. bberwyn photo

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Tourists hiking on Deception Island. bberwyn photo

Staff Report

FRISCO — The tiny ice-free fringes of Antarctica are especially prone to ecosystem disruption, including invasive species, an Australian science team warned earlier this year after taking a close look at how human use is concentrated in those slivers of dry land.

Antarctica has over 40,000 visitors a year, and more and more research facilities are being built in the continent’s tiny ice-free area. Most of the Antarctic wildlife and plants live in the ice-free areas – and this is also where people most visit.

Most tour operators in Antarctica follow strict guidelines set to protect ecosystems, including at least basic decontamination procedures, but those measures might not be enough, especially as global warming makes ice-free zones more susceptible to invasive species. Continue reading

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Climate studies probe growth of Antarctic sea ice

‘The planet as a whole is doing what was expected in terms of warming. Sea ice as a whole is decreasing as expected …’

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Sea ice is expanding around Antarctica, and scientists say wind, snow and melting land ice are key factors in the growth bberwyn photo.

The map at right shows Antarctic ice concentration on September 22, 2014, the date of the record high. Areas where the surface was less than 15% ice covered are deep blue; areas that were up to 100% ice covered are shades of light blue to white. The orange line shows the 1981-2010 median extent for September 22. (Median means in the middle: half of the years in the record had smaller ice extents than this, and half had larger extents.) The graph below the map shows daily Antarctic sea ice extent over the course of the year. The black line traces the 1981-2010 average, and the gray shading shows the range of variability (2 standard deviations from the mean). The previous record high extent (2013) is a dashed green line; the 2014 year to date is a light green line. NSIDC reported that the 2014 extent rose nearly 4 standard deviations above the 1981-2010 mean.

The map above shows Antarctic ice concentration on September 22, 2014, the date of the record high. Areas where the surface was less than 15% ice covered are deep blue; areas that were up to 100% ice covered are shades of light blue to white. The orange line shows the 1981-2010 median extent for September 22. (Median means in the middle: half of the years in the record had smaller ice extents than this, and half had larger extents.)
The graph below the map shows daily Antarctic sea ice extent over the course of the year. The black line traces the 1981-2010 average, and the gray shading shows the range of variability (2 standard deviations from the mean). The previous record high extent (2013) is a dashed green line; the 2014 year to date is a light green line. NSIDC reported that the 2014 extent rose nearly 4 standard deviations above the 1981-2010 mean. Courtesy NOAA.

By Summit Voice

FRISCO — Along with shifting wind patterns in the southern hemisphere, melting land ice may be contributing to recent record extents of floating sea ice around Antarctica. The melting ice and snow adds fresh water — which freezes morel easily — to the salty Southern Ocean, scientists said in a release this week, explaining the multi-year trend of expanding Antarctic sea ice.

But the increase doesn’t balance the loss of sea ice at the other end of the Earth. Arctic sea ice has declined by an average of 20,800 square miles per year; the Antarctic has gained ice at a rate of about a third of that, by an average of 7,300 square miles per year.

This week, the National Snow and Ice Data Center (NSIDC) reported that Antarctic sea ice extent set a new record high for daily extent: 20.11 million square kilometers (7.76 million square miles), the highest since satellite observations started in the late 1970s.

In July, a European study called into question the recent measurements, citing inconsistencies in computer models.

Other studies suggest the growth is only temporary, and that Antarctic sea ice will ultimately decline dramatically in the decades ahead.

The ice trackers matched this year’s late season ice surge with strong southerly winds blew over the Weddell Sea. Without any nearby land masses to constrain growth, those winds tend to push the ice northward. Continue reading

Climate: Polar paradox?

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September trend for Arctic sea ice extent is down, down, down. Courtesy NSIDC.

Arctic sea ice bottoms out; Antarctic sea ice hits new high

Staff Report

FRISCO — Even without remarkably warm weather patterns across the Arctic, summer sea ice dropped to the sixth-lowest extent on record this year, while at the other end of the Earth, sea ice around Antarctica swelled to a record extent.

Through 2014, Arctic sea ice has now been declining at a rate of 13.3 percent per decade relative to the 1981 to 2010 average. The ten lowest September ice extents over the satellite record have all occurred in the last ten years. Continue reading

How does the Southern Ocean regulate global climate?

Major research project to examine carbon cycling, circulation dynamics

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A new research project will help explain how the Southern Ocean helps regulate the global climate. bberwyn photo.

Staff Report

FRISCO — Even though it’s eparated from the rest of the world’s oceans by a strong circulation of currents and a distinct temperature gradient, the Southern Ocean is known to be a key driver of global climate and carbon cycles.

Climate researchers and oceanographers may soon know a lot more about the enigmatic ocean as they deploy hundreds of robotic floats deployed around Antarctica in a six-year, $21 million research project aimed at understanding ocean dynamics, chemistry and carbon cycling. The new instruments will increase the flow of Southern Ocean data 30-fold. Continue reading

Study shows why Penguins need more protection

‘If we don’t worry about the imminent threats now, it’s probably not worth worrying about the medium-term future’

Gentoo penguins and the S/V Professor Molchanov at sea.

Gentoo penguins and the S/V Professor Molchanov. bberwyn photo.

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A penguin dives in and out of the icy waters near the Antarctic Peninsula. bberwyn photo.

By Bob Berwyn

FRISCO — The world’s penguins could use a little help, a team of  leading conservation biologists said last month, announcing results of a study that systematically assessed global risks to the southern hemisphere sea birds.

While global warming remains a long-term threat, other impacts, primarily related to human activities, are a more clear and present danger, the scientists said, advocating for a more widespread network of marine protected areas to buffer penguins from pollution, tourism and fishing.

“We need to address some of these issues before we think about resilience to climate change,” said Dr. Phil Trathan, head of conservation biology with the British Antarctic Survey. “If we don’t worry about the imminent threats now, it’s probably not worth worrying about the medium-term future,” Trathan said, explaining that penguins living and breeding in southern Africa and South America face the highest risks.

“If you want to create resilient populations, deal with some of the immediate threats, and where the threats are most evident is where penguins inhabit areas close to mankind,” he said. Continue reading

Climate study shows how melting ice is raising sea level around Antarctica

‘The interaction between air, sea and ice in these seas is central to the stability of the Antarctic Ice Sheet and global sea levels’

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A new study tracks global warming impacts around Antarctica. bberwyn photo.

By Summit Voice

FRISCO — Global warming is upsetting the delicate balance between Antarctic ice, air and sea, University of Southampton scientists said this week, releasing results of a study showing a rapid rise in sea level around the frozen continent.

Based on an analysis of 19 years worth of satellite data, the researcher said sea level around the coast of Antarctica has climbed 2 centimeters more than the global average, driven almost entirely by an increase in freshwater, which is less dense than saltwater. That can cause localized increases in sea level, said Craig Rye, lead author of the paper published in the journal Nature Geoscience. Continue reading

Antarctica: Life beneath the ice

Antarctic peak.

Science mission finds microbial life beneath Antarctic ice sheets. bberwyn photo.

Simple organisms process basic elements to survive

Staff Report

FRISCO —Tiny organisms living beneath the vast Antarctic ice fields can convert ammonium and methane into the energy required for growth, surviving in one of the most unlikely environments on Earth, according to scientists who studied a subsurface lake that hasn’t seen sunlight for millions of years.

“We were able to prove unequivocally to the world that Antarctica is not a dead continent,” said Montana State University professor John Priscu, the chief scientist of the U.S. project called WISSARD that sampled the sub-ice environment. Continue reading

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