INTRODUCTION FOR NEW RECIPIENTS
If you are receiving one of these emails for the first time, we met (if only fleetingly) at the recent Wild Law weekend so have been added you to the distribution accordingly. Its purpose is flag up key issues relating to Wild Law, the precariousness of our position in the face of environmental threats and other information otherwise easily missed.The frequency is perforce very low, though there is likely to be a slight flurry of half a dozen or so in the short-term to catch up on several major developments.
Should you wish to get a better feel of what is involved, current and previous emails are posted on the pensive prognosticator where most of the traffic from the now defunct Wild Law forum hosted by forumality.com can also be found. All are welcome to post comments and discuss if so moved.
However if this is not to your wishes please let me know and I shall immediately remove you with apologies for the presumption.
PLAIN TEXT READERS
If you are reading this email as plain text and have difficulty locating links please view the blog copy posted at
http://pensiveprognosticator.blogspot.com
If you could also let me know I would be grateful, particularly if this expedient does not work well for you.
And so to the Arctic...
WINTER RETURNS
The arctic summer came to an end on 14 September when the thaw ceased and freezing conditions returned.
The ice is now reforming as the seas freeze and the snows fall, and assuming historical weather patterns continue to hold this will continue until next March, when the next thaw should commence.
This report summarises the main scientific conclusions at the season's end, where disquieting trends underly the superficial data on the extent of this summer's melt.
As this might have made for a rather dry read, it is worth noting that it also acts as as background for next email which contains developments of the gravest significance which broke at the end of September, and which rightly should have us all standing by at the emergency exits ready to abandon ship in short order. As it is so critical to our entire situation the intention is to get it to you as soon as I can.
All emphasis by bolding in the quotes which follow is mine.
ICE LOSS
In the end this summer's melt did not break the 2007 record, which is probably taken as reassurance that things aren't really so perilous after all in quarters where that is what people hope to believe. But it did come within 390,000 square kilometres or 9% of the all-time minimum, as these figures summarised by the International Polar Foundation in an article entitled Long Term Arctic Sea Ice Decline Continues show:
September 2005: 5.57 million km2
September 2007: 4.28 million km2
September 2008: 4.67 million km2
It all looks good until you realise that 2007 was 'perfect storm' conditions for melting, whilst this summer was for the most part somewhat unfavourable from that point of view. June and July were cool and cloudy, and the rates of melting indifferent. Nonetheless the 2008 September low was still 34% below the long-term average from 1979 to 2000, and only 9% shy of 2007.
The reality was exposed in August, when the summer finally got going, when the NASA Goddard Space Flight Institute reported the rate of melting was the fastest ever recorded - and at a gob-smacking rate, too:
'From August 1 to August 31, NASA data show that arctic sea ice extent declined at a rate of 32,700 square miles [84,693 km2] per day, compared to a rate of about 24,400 square miles [63,196 km2] per day in August 2007. Since measurements began, the arctic sea ice extent has declined at an average rate of 19,700 miles per day at the point when the extent reaches its annual minimum.'
The 2008 rate of melting represents an increase of 66% over the average quoted, and a massive 34% over what were unprecedented rates in 2007, as the National Snow and Ice Data Center reported on 02 October. One reason for this was the increasing vulnerability of the ice because with each year's losses, more and more of what remains is one year old ice at the start of the season. This simply does not have the thickness to resist melting conditions, so melts much faster than the perennial ice it has replaced.
Or, as they added:
'In March 2008, thin first-year ice covered a record high 73% of the Arctic Basin. While this might seem like a recovery of the ice, the large extent masked an important aspect of sea ice health; thin ice is more prone to melting out during summer. So, the widespread thin ice of spring 2008 set the stage for extensive ice loss over the melt season.'
And
“Warm ocean waters helped contribute to ice losses this year, pushing the already thin ice pack over the edge. In fact, preliminary data indicates that 2008 probably represents the lowest volume of Arctic sea ice on record, partly because less multiyear ice is surviving now, and the remaining ice is so thin.”
To beef up on that point, we only have to consider this key quote from a University of Colorado press release from January (i.e. not including this summer's melt)
'The team used satellite data going back to 1982 to reconstruct past Arctic sea ice conditions, concluding there has been a nearly complete loss of the oldest, thickest ice and that 58 percent of the remaining perennial ice is thin and only 2-to-3 years old, said the lead study author, Research Professor James Maslanik of CU-Boulder's Colorado Center for Astrodynamics Research. In the mid-1980s, only 35 percent of the sea ice was that young and that thin according to the study, the first to quantify the magnitude of the Arctic sea ice retreat using data on the age of the ice and its thickness, he said.'
In fact the position at the end of this summer can best be appreciated by taking a look at the excellent images in the 24 September summary produced by NSIDC which illustrate graphically the extent of ice remaining, the predominance of young ice, and also the odd fact that the pattern of winds was partially responsible for the 2007 record not being broken this year. To qualify as ice, the sea has to contain a mere 15% of ice - there is not nearly as much as the raw figures quoted above suggest. This summer, the winds acted to disperse the ice over a large area of water, thus qualifying a greater area as ice, whilst in 2007 the opposite occured.
ARCTIC ICE SHELVES
The Arctic ice shelves faired very badly this year, and seem to be in terminal decline, as there is no foreseeable way they can recover short of the next ice age. Here is a repeat the BBC story reported in the last update which informs that:
'The ice shelves in Canada's High Arctic have lost a colossal area this year, scientists report.'
'The floating tongues of ice attached to Ellesmere Island, which have lasted for thousands of years, have seen almost a quarter of their cover break away.
'One of them, the 50 sq km (20 sq miles) Markham shelf, has completely broken off to become floating sea-ice.'
'As well as the complete breakaway of the Markham, the Serson shelf lost two sections totalling an estimated 122 sq km (47 sq miles), and the break-up of the Ward Hunt has continued.'
And, by way of interpretation
'Loss of ice in the Arctic, and in particular the extensive sea-ice, has global implications. The "white parasol" at the top of the planet reflects energy from the Sun straight back out into space, helping to cool the Earth.
'Further loss of Arctic ice will see radiation absorbed by darker seawater and snow-free land, potentially warming the Earth's climate at an even faster rate than current observational data indicates.'
The link has some telling before and after satellite images well worth a look too.
GREENLAND
Has also taken a big hit this year, and we found out that a lot more melting is going on there than we previously realised:
SMALL GLACIERS – NOT LARGE – ACCOUNT FOR MOST OF GREENLAND’S RECENT LOSS OF ICE, STUDY SHOWS
'The recent dramatic melting and breakup of a few huge Greenland glaciers have fueled public concerns over the impact of global climate change, but that isn’t the island’s biggest problem.
A new study shows that the dozens of much smaller outflow glaciers dotting Greenland’s coast together account for three times more loss from the island’s ice sheet than the amount coming from their huge relatives'
'...scientists at Ohio State University reported that nearly 75 percent of the loss of Greenland ice can be traced back to small coastal glaciers'
'Aside from Antarctica, Greenland has more ice than anywhere else on earth.'
While 09 October the IPF brought brought us the story Satellite Data Reveals Extreme Summer Snowmelt and Record Number of Melting Days in Northern Greenland
'The northern part of the Greenland Ice Sheet underwent extreme snowmelt during the summer of 2008, and large portions of the ice sheet experienced a record number of melting days
'Dr. Tedesco said that the melting, which lasted 18 days longer than previous maximum values and had a melting index three times greater than the 1979-2007 average, was "extremely interesting," as northern Greenland is usually much colder than southern Greenland, which experienced record melting in summer 2007.'
LAST WORDS
Dr Walt Meier of NSIDC at Boulder, Colorado in an interview with the BBC
'I think this summer has been more remarkable than last year, in fact, because last year we had really optimal conditions to melt a lot of ice.
'We had clear skies with the Sun blazing down, we had warm temperatures, and winds that pushed the ice edge northwards," he told BBC News.
'We didn't have any of this this year, and yet we still came within 10% of the record; so people might be tempted to call it a recovery, but I don't think that's a good term, we're still on a downwards trend towards ice-free Arctic summers.'
The NASA Goddard scientist previously quoted said
'Based on what we've learned over the last 30 years, we know that the perennial ice cover is now in trouble. You need more than just one winter of cooling for the ice to recover to the average extent observed since the measurements began. But the trend is going the other way. A warming Arctic causes the surface water to get warmer, which delays the onset of freeze up in the winter and leads to a shorter period of ice growth. Without the chance to thicken, sea ice becomes thinner and more vulnerable to continued melt.'
And two scientists here, quoted from a short and rather indifferent article by the New Scientist, which some might find useful nonetheless because it runs very quickly through the main drivers of ice loss.
'"We are now well outside the range of natural variability," says Meier. "It is clear from how low the ice extent has been recently, the significant long-term trend, and the way the ice-cover is responding to atmospheric conditions and ocean circulation, that we've entered an entirely new regime of the Arctic sea ice".
"I think most glaciologists would be very surprised if the Arctic went back to normal," agrees Graversen.'
From all of this is seems overridingly apparent that the loss of the Arctic is unstoppable and is likely to continue at an unprecedented rate. Unless we have a succession of extremely hard winters to beef up the perennial ice in a significant way - which in itself seems improbable because all the trends are in the opposite direction, as would be expected with global warming as it is - it seems likely that the next hot summer will cause loss of ice on a massive scale, and probably considerably more break up than we have so far seen. A few summers like that and there will be precious little left - with all the dire consequences that entails.
NEXT ISSUE
This summary has dealt with the physical extent of Arctic ice, which is critical for Earth's albedo, for the moderating effect on the planet's average temperature, for their role in the circulatory systems in the atmosphere and the ocean. It is also critical for being the sole habitat of animals like the polar bear and home to unique peoples such as the Inuits.
Yet for scientists considering climate change there remains another question which is perhaps the most loaded of all - the moderating effect on the surrounding environment. At the end of September the news no one ever wanted to hear broke in this area. Because of its potentially devastating nature I will cover it separately in the next newsletter and as quickly as practicalities make possible.
To close with something for the soul and the heart, here's a sublime lament for the Arctic, though he though he would have been entirely unconscious of that when he wrote it. Nice video too of what hangs in the balance. For those with 4.50 to spare out of the chaos.
With thanks for your attention
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