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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

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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

Climate: Arctic sea ice swallows CO2

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Frost flowers forming atop early winter ice may play an important role in drawing CO2 from the atmosphere. bberwyn photo.

Frost flowers also play role in global carbon cycle

Staff Report

FRISCO — Along with cooling the Earth by reflecting sunlight back into space, Arctic sea ice also helps directly remove heat-trapping CO2 from the atmosphere, Danish scientists reported this week.

As Arctic summers warm, there may be an acceleration of global warming, because reduced sea ice in the Arctic will remove less CO2 from the atmosphere.

“If our results are representative, then sea ice plays a greater role than expected, and we should take this into account in future global CO2 budgets”, said Dorte Haubjerg Søgaard, PhD Fellow, Nordic Center for Earth Evolution, University of Southern Denmark and the Greenland Institute of Natural Resources, Nuuk. Continue reading

Global warming: New NASA aerial mission to explore impacts of Arctic sea ice loss

Arctic cloud formation still a climate wild card

Sun glint off a sea ice lead in an otherwise heavily ridged ice pack, Canada Basin (Arctic Ocean). Credit: NASA/Sinead Farrell

Sun glints off a sea ice lead in an otherwise heavily ridged ice pack, Canada Basin (Arctic Ocean). Credit: NASA/Sinead Farrell

STAFF REPORT

FRISCO — The ongoing loss of Arctic sea ice is probably already affecting weather and climate in the mid-latitudes of the northern hemisphere. Researchers aren’t exactly sure of how, but there’s been plenty of speculation, mostly focused around changes in the jet stream.

Climate scientists may know a bit more in a few years after they study the results of a new NASA field campaign studying the effect of sea ice retreat on Arctic climate. The Arctic Radiation IceBridge Sea and Ice Experiment (ARISE) will conduct research flights Aug. 28 through Oct. 1, covering the peak of summer sea ice melt. Continue reading

Climate: Rethinking the Arctic carbon cycle

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Permafrost processes will play a big role in Earth’s climate for decades to comes.

New findings critical to climate calculations

Staff Report

FRISCO — Sunlight is the key factor in the process of converting Arctic permafrost carbon into atmospheric carbon dioxide, scientists concluded in a new study that could dramatically change the scientific understanding of the planet’s carbon cycle and the consequences of a permafrost meltdown.

The finding is particularly important because climate change could affect when and how permafrost is thawed, which begins the process of converting the organic carbon into CO2. The research was funded by the National Science Foundation and published in the journal Science. Continue reading

Climate: What happens in the Arctic doesn’t stay in the Arctic

The Fram Strait is a key link in the global ocean circulation system, as the passage for most of the Arctic sea ice exiting the region.

The Fram Strait is a key link in the global ocean circulation system, as the passage for most of the Arctic sea ice exiting the region.

Detailed ocean sediment layers paint clear picture of link between Arctic sea ice movement and ocean currents

Staff Report

FRISCO — An extraordinarily clear deposit of layered seafloor sediments has helped researchers explain the connection between Arctic sea ice movement and the movement of key ocean currents that redistribute warm water across the northern hemisphere.

Specifically, the new study by scientists with the Alfred Wegener Institute in Germany looked at the movement of sea ice through the Fram Strait, between Greenland Svalbard, finding that, when massive quantities of Arctic ice melt and move south through the strait, the Gulf Stream slows, cooling the climate in Europe. Continue reading

Study tracks rapid ice age climate shifts

A cyclonic storm spins over the center of the Arctic Ocean. Photo courtesy NASA Earth Observatory

A cyclonic storm spins over the center of the Arctic Ocean. Photo courtesy NASA Earth Observatory.

Findings show delicate balance of ice sheets, winds and ocean currents

Staff Report

FRISCO — The superstorm depicted in “The Day After Tomorrow” may be completely implausible, but that doesn’t mean the Earth’s climate system is always as stable as it seems now.

New research by a team of scientists at the Alfred Wegener Institute shows how there may have been significant shifts in ocean circulation and wind patterns that happened in the span of just a few decades — not even the blink of an eye by geological time standards. Continue reading

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