Fire Earth

Earth is fighting to stay alive. Mass dieoffs, triggered by anthropogenic assault and fallout of planetary defense systems offsetting the impact, could begin anytime!

Feeling Cold?

Posted by feww on February 8, 2011

AO Blowing Arctic Ice at YOU

Arctic Sea:  Lowest extent ever recorded for January

Arctic oscillation persisted in a strong negative phase for most of January, keeping the Arctic ice extent low, NSIDC said.

Arctic sea ice keeps the polar regions cool and moderates global climate by reflecting sunlight back into space. “Arctic sea ice has declined dramatically over at least the past thirty years, with the most extreme decline occurring  in the summer melt season.”

Sea Ice Extent for January 2011 declined to 13.55 million square kilometers (5.23 million square miles). The magenta line shows the 1979 to 2000 median extent for the month. The black cross marks the geographic North Pole.

Highlight of NSIDC Report

  • January air temperatures over Arctic rose by 2 to 6 degrees Celsius (4 to 11 degrees Fahrenheit) above normal.
  • Over the eastern Canadian Arctic Archipelago, Baffin Bay/Davis Strait and Labrador Sea, temperatures rose by at least 6 degrees Celsius (11 degrees Fahrenheit) above average.
  • “As in December 2010, the warm temperatures in January came from two sources: unfrozen areas of the ocean continued to release heat to the atmosphere, and the wind patterns accompanying the negative phase of the Arctic oscillation brought warm air into the Arctic.
  • “Near the end of January the negative Arctic oscillation pattern broke down and turned positive, which usually favors ice growth. It is unclear how long it will remain in a positive mode.”
  • January 2011 saw the lowest ice extent for the month since satellite records began 31 years ago. The linear rate of decline for the month is –3.3% per decade.
  • Arctic ice extent increased at an average of 42,800 square kilometers (16,500 square miles) per day in January, which is about average.

Source: The National Snow and Ice Data Center (NSIDC). Click images to enlarge.

Orange line in the top image and gray line in time series (above) indicate 1979 to 2000 average ice extent for the day shown.
Credit: NSIDC. Click image to enlarge.

Monthly January ice extent for 1979 to 2011 indicated a decline of 3.3% per decade.
Source: NSIDC. Click image to enlarge.

Negative AO in December 2010 and January 2011,Keeping NH Ice Cold

The average Arctic sea ice concentration for January 2011, processed by AMSR-E aboard NASA’s Aqua satellite. The red line shows the average sea ice extent recorded for the month of January from 1979 to 2000. Source: NASA-EO

Overview of conditions

Arctic sea ice extent averaged over January 2011 was 13.55 million square kilometers (5.23 million square miles). This was the lowest January ice extent recorded since satellite records began in 1979. It was 50,000 square kilometers (19,300 square miles) below the record low of 13.60 million square kilometers (5.25 million square miles), set in 2006, and 1.27 million square kilometers (490,000 square miles) below the 1979 to 2000 average.

Ice extent in January 2011 remained unusually low in Hudson Bay, Hudson Strait (between southern Baffin Island and Labrador), and Davis Strait (between Baffin Island and Greenland). Normally, these areas freeze over by late November, but this year Hudson Bay did not completely freeze over until mid-January. The Labrador Sea remains largely ice-free. Source (NSIDC)

Any links with mid-latitude weather?

High and low atmospheric pressure patterns for January 2011 (left) and the January 1968-1996 average (right). Yellows and reds show higher pressures; blues and purples indicate lower pressures, as indicated by the height of the 850 millibar pressure level above the surface, called the pressure surface. Normally, the pressure surface is nearer to the surface around the pole, winds follow the pressure contours around the pole (the polar vortex), and cold air is trapped in the Arctic. This year, the pressure surface is allowing cold air to spill out of the Arctic into the mid-latitudes. Source: NSIDC courtesy NOAA/ESRL PSD

AO in Strong Negative Phase

Warm conditions in the Arctic and cold conditions in northern Europe and the U.S. are linked to the strong negative mode of the Arctic oscillation. Cold air is denser than warmer air, so it sits closer to the surface. Around the North Pole, this dense cold air causes a circular wind pattern called the polar vortex , which helps keep cold air trapped near the poles. When sea ice has not formed during autumn and winter, heat from the ocean escapes and warms the atmosphere. This may weaken the polar vortex and allow air to spill out of the Arctic and into mid-latitude regions in some years, bringing potentially cold winter weather to lower latitudes. Source (NSIDC)

Related Links:

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.