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Snow and Ice in the Northern Hemisphere 2011/2012
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The USCGC Healy Icebreaker has been on a mission around the north Pole over the past month or so, and you can see hourly webcam images from the deck here.
Latest one today, as the ship is around 800 km south of the Pole, north of Canada.
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From Dr Masters blog :Arctic sea ice extent hit its minimum on September 9 this year, falling to its second lowest value since satellite measurements began in 1979, according to the National Snow and Ice Data Center . More than one third (35%) of the Arctic sea ice was missing this summer, compared to the 1979 - 2000 average. This is an area about the size of the Mediterranean Sea. The 2011 sea ice minimum was very close to the all-time record low set in 2007; in fact, the University of Bremen rated the 2011 loss the greatest on record. For the fourth consecutive year, and fourth time in recorded history, ice-free navigation was possible in the Arctic along the coast of Canada (the Northwest Passage), and along the coast of Russia (the Northeast Passage.) Mariners have been attempting to sail these waters since 1497.
While the record low sea ice year of 2007 was marked by a very unusual 1-in-20 year combination of weather conditions that favored ice loss (including clearer skies, favorable wind patterns, and warm temperatures), 2011's weather patterns were much closer to average. The fact we pretty much tied the record for most sea ice loss this year despite this rather ordinary weather is a result of the fact that large amounts of thicker, multi-year ice has melted or been flushed out of the Arctic since 2007. As a result of the loss of this old, thick ice, both 2010 and now 2011 set new records for the lowest volume of sea ice in the Arctic, according the University of Washington PIOMAS model. Given the very thin ice now covering most of the Arctic, we can expect truly dramatic sea ice loss the next time 1-in-10 year or 1-in-20 year warmth and sunshine invades the Arctic. We are definitely on pace to see the Arctic virtually sea ice-free in summer by 2030, as predicted by several leading Arctic sea ice scientists. I expect we'll see more than half of the Arctic ice gone and the North Pole liquid instead of solid by the summer of 2020, and probably sooner.
Figure 1. Arctic sea ice extent in 2011 (blue line) compared to the record low year of 2007 (dashed green line) and average (thick grey line.) Image credit: National Snow and Ice Data Center .
When was the last time the Arctic was this ice-free?
We can be sure the Northwest Passage was never open for ice-free navigation--particularly ice-free navigation for multiple years in a row--between 1900 and 2000, as we have detailed ice edge records from ships (Walsh and Chapman, 2001). It is very unlikely the Passage was open between 1497 and 1900, since this spanned a cold period in the northern latitudes known as "The Little Ice Age". Ships periodically attempted the Passage and were foiled during this period, and the native Inuit people have no historical tales of the Passage being navigable at any time in the past.
The Northwest passage may have been open multiple years in a row for ice-free navigation at some period during the Medieval Warm Period, between 1000 and 1300 AD. A better candidate was the period 6,000 - 8,500 years ago, when the Earth's orbital variations brought more sunlight to the Arctic in summer than at present. Funder and Kjaer (2007) found extensive systems of wave generated beach ridges along the North Greenland coast that suggested the Arctic Ocean was ice-free in the summer for over 1,000 years during that period. Prior to that, the next likely time was during the last inter-glacial period, 120,000 years ago. Arctic temperatures then were 2 - 3°C higher than present-day temperatures, and sea levels were 4-6 meters higher.
However, it is possible that the recent summer low-ice conditions in the Arctic are unprecedented for the past 800,000 years, according to a 2011 press release by Project CLAMER, a European group dedicated to climate change and European marine ecosystem research. They found that a tiny species of plankton called Neodenticula seminae that went extinct in the North Atlantic 800,000 years ago has become a resident of the Atlantic again, having drifted from the Pacific through the Arctic Ocean thanks to dramatically reduced polar ice. The 1999 discovery represents "the first evidence of a trans-Arctic migration in modern times" related to plankton, according to the UK-based Sir Alister Hardy Foundation for Ocean Science, whose researchers warn that "such a geographical shift could transform the biodiversity and functioning of the Arctic and North Atlantic marine ecosystems."
It is possible we'll have a better idea of historical ice-free conditions in the Arctic in the next few years. A new technique that examines organic compounds left behind in Arctic sediments by diatoms that live in sea ice give hope that a detailed record of sea ice extent extending back to the end of the Ice Age 12,000 years ago may be possible (Belt et al., 2007). The researchers are studying sediments along the Northwest Passage in hopes of being able to determine when the Passage was open during the past 12,000 years.
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=19320 -
From newscientist.com - Arctic ice falls to near record low
This mosaic of satellite images over the Arctic Ocean shows ice levels nearing a record low set in 2007. Acquired from the European Space Agency's radar satellite Envisat ASAR, the blue areas represent regions where ice accounts for more than 80 per cent of the sea surface. ASAR captured the high resolution images over the course of three days beginning 9 September. The satellite's radar penetrates the obscuring effects of the Arctic's frequent dark hours and thick cloud cover more>>>
Have a weather station?, why not join the Ireland Weather Network - http://irelandweather.eu/
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No snow in Lappland yet, but has there been an earthquake??!!
http://alk.tiehallinto.fi/alk/english/kelikamerat/kamera-C1450801.html
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No snow in Lappland yet, but has there been an earthquake??!!
http://alk.tiehallinto.fi/alk/english/kelikamerat/kamera-C1450801.html
Snow covered by next Saturday I'd bet
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I did up this animation using daily charts that monitor snow and ice cover for the Eurasian continent from the NOAA's National Ice Centre
(Just to note that animation may be slow to load at first as there are 366 separate images involved)
The starting time in the animation is October 8th 2010 and finishes on the same date one year later (i.e, yesterday!) Both starting and finishing images are 3 seconds long so as to run side by side to give a visual comparison of snow and ice extent over the region on the same date between both years.
Just going by a quick, unanalytical eye over, it does seem the the snow line over the Siberian region was extended just a little bit further south this time last year; having said that though, ice extent along the northeastern/eastern coast of Greenland seems to be slightly greater than at this stage last year, no doubt due to the lack of any substantial warmth making its way in over the broader north Atlantic region throughout the summer period.
The chart below for example, shows the mean monthly sea level pressure pattern for June this year over the northeast Atlantic region:
Image Source: European Centre for Medium-Range Weather Forecasts (ECMWF)
Dominant was those darn Polar northwesterlies extending through eastern Greenland right down over the northeast Atlantic region with sub tropical air masses being kept well and truly in their place by low pressure and southerly tracking Jet Streams. It is likely that the mean MSLP analysis charts for July and August this year will show something more or less similar to this scenario as well when they are released.
Anyway, here's to a mild, wild and thunderous Winter 2011/2012 season ahead!
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Join Date:Posts: 14592
First it was the Swedes turn, now the Norwegian motorists have been caught off guard.
(source)
Strong winds and snow over 300-400m altitude in the north of Norway and 600-800m in southern half.
(They've been warning for the past two weeks that people need to put on their winter tyres, snow is hardly a surprise to them!)0 -
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