The US's NOAA duties include regular reports and the latest prepares us for another of those winters that we just don't understand. For example, the strangely low [ozone] in March this year led to high ultra-violet levels in both Arctic and sub Arctic regions. Most scientists believed this due to the very cold stratosphere, resulting in slow ozone formation. We can but hope for something better in a few months time!
With global shifting of atmospheric wind patterns, the Arctic itself is warmer while lower latitudes are cooling. For the last two years, severe cold weather hit north-east America, northern Europe and eastern Asia. Wind patterns that affect so many people also affect the uninhabited Arctic in the opposite way. Another excellent descriptive NOAA map shows us the vital difference, unfortunately failing to show us the Eurasian situation as clearly the US:
Left: Winter temperatures, 2010â€2011 - Right: "Classic" NAO pattern; Credit: Data courtesy Marty Hoerling, NOAA ESRL; Map by Climate.gov Team
Sadly, even worse effects included a record loss of ice sheets and an overall trend of glacier and ice-cap loss; record low and late snow cover in Eurasia and similar lake ice losses.
Biological productivity may be increasing since 1998 as the sea warms. Polar bears and walrus do not agree that this is a good thing, as their ice disappears. Twelve polar bear populations are not declining, but the other seven have problems, two of them directly connected with loss of sea ice habitat. Alaska is suffering an invasion from thousands of walrus as the Chukchi Sea loses its ice.
Left Image Credit: Captain Budd Christman, NOAA Corps; Right Image Credit: Dr. Pablo Clementeâ€Colon, NOAA National Ice Center
Tagged Bowhead whales however have indicated that they have discovered the Northwest Passage and two separate populations can now sing to each other!
The ice loss from glaciers and sea ice as well as lower snow levels has raised air temperature throughout the Arctic.In 2011, near-surface air temperature was 1.5oC higher than the 1981-2010 period. Such "Arctic Amplification," have air temperature changes 2X or 3X greater than those found at lower latitudes. The theory goes that darker sea surface absorbs solar energy much more than the reflective ice, causing such rapid increases. Look at the Eurasian increases on the right of this map. Only Canada can compete with the increase, where Baffin Bay is one of the sources of open water.
Credit: Data courtesy NOAA ESRL; Map by Climate.gov Team
Ecosystems are "greening" on the tundra due to land temperature increases and an increase in open water. Again, the effect on the water is also chemical as the pH decreases due to a more rapid uptake of CO2 at the sea/air interface. Prof. Howie Epstein from the University of Virginia has access to photographs showing north Alaskan tundra vegetation going back to the 1950s. Here are some dwarf alders growing well with an ecologically-interesting pattern in the brief summer.
Credit: Greg Balogh, U.S. Fish and Wildlife Service
The huge Eurasian tundra has been clocked as going green two weeks earlier than 30 years ago. Research is ongoing too on the relationship between record permafrost temperatures (at 20m) and adaptations by the flora. In the ocean, of course similar effects have caused phytoplankton blooms for millions of square kilometres.
Sea ice has suffered a decline in summer extent, while its age is decreasing (ie. less than half the sea ice at the winter maximum has survived more than one summer) as the warmer and fresher ocean surface waters change all around them. Alaskan and Siberian coasts suffered the most as can be seen. Presumably Greenland's coasts are nearer the pole:
Credit: NSIDC & NASA Earth Observatory
Don Perovich of the Cold Regions Research and Engineering Laboratory quotes, "The past five years have had the five smallest September ice extents showing that Arctic sea ice has not recovered from the large decrease observed in 2007." His idea is that a new state of the sea ice and ocean implies long-term problems especially but not exclusively for marine ecosystems.
Perhaps this useful American based report can now be joined with a similar package from the Sino-Nordic end of the map. Scientists fortunately have few national barriers, but if US funding were withdrawn from NOAA, it would be useful to have some alternative.