Monday, August 13, 2012

Getting the picture

Have a look at the picture below. It shows a graph based on data calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) developed at the Applied Physics Laboratory/Polar Science Center at the University of Washington.
image from arctische pinguin - click to enlarge
The PIOMAS data for the annual minimum values are the black dots. The trend (in red) is added by Wipneus and points at 2015 as the year when ice volume will reach zero. Note that the red line points at the start of the year 2015. The minimum in September 2014 will be already be close to zero, with perhaps a few hundred cubic km remaining just north of Greenland and Canada.
image from arctische pinguin - click to enlarge
Above image, again based on PIOMAS data, shows trends added by Wipneus for each month of the year. The black line shows that the average for the month September looks set to reach zero a few months into the year 2015, while the average for October (purple line) will reach zero before the start of the year 2016. Similarly, the average for August (red line) looks set to reach zero before the start of the year 2016.

In conclusion, it looks like there will be no sea ice from August 2015 through to October 2015, while a further three months look set to reach zero in 2017, 2018 and 2019 (respectively July, November and June). Before the start of the year 2020, in other words, there will be zero sea ice for the six months from June through to November.

Actually, events may unfold even more rapidly. As the ice gets thinner, it becomes more prone to break up if there are storms. At the same time, the frequency and intensity of storms looks set to increase as temperatures rise and as there will be more open water in the Arctic Ocean.


Above photo features Peter Wadhams, professor of Ocean Physics, and Head of the Polar Ocean Physics Group in the Department of Applied Mathematics and Theoretical Physics, University of Cambridge. Professor Wadhams has been measuring the sea ice in the Arctic for the 40 years, getting underneath the ice with the assistance of submarines, collecting ice thickness data and monitoring the thinning of the ice. This enabled 1970s data and 1980s data to be compared, which showed that the ice had thinned by about 15%. Satellite measurements only started in 1979.

Thinning of the ice is only one of the problems. "The next stage will be a collapse," Professor Wadhams warns, "where the winter growth is more than offset by the summer melt. If we look at the volume of ice that is present in the summer, the trend is so rapidly downwards that this collapse might happen within three or four years."

Apart from melting, strong winds can also influence sea ice extent, as happened in 2007 when much ice was driven across the Arctic Ocean by southerly winds. The fact that this occurred can only lead us to conclude that this could happen again. Natural variability offers no reason to rule out such a collapse, since natural variability works both ways, it could bring about such a collapse either earlier or later than models indicate.

In fact, the thinner the sea ice gets, the more likely an early collapse is to occur. It is accepted science that global warming will increase the intensity of extreme weather events, so more heavy winds and more intense storms can be expected to increasingly break up the remaining ice, both mechanically and by enhancing ocean heat transfer to the under-ice surface.

Recent events in the Arctic underline this warning. A huge cyclone battered the sea ice early August 2012. The image below, from The Cryosphere Today, shows a retreat in sea ice area to 3.09958 million km2 on the 222nd day of 2012, down from 3.91533 million km2 on the 212th day of 2012, i.e. 815,750 km2 less in ten days. Or, more than one-fifth less in just ten days.

Image from  The Cryosphere Today - click to enlarge

Sunday, August 12, 2012

Charting Mankind’s Arctic Methane Emission Exponential Expressway to Total Extinction in the Next 50 Years

By Malcolm P.R. Light
August 10, 2012

Abstract

The exponential increase in the Arctic atmospheric methane derived from the destabilization of the subsea Arctic methane hydrates is defined by both the exponential decrease in the volume of Arctic sea ice due to global warming and the exponential decrease in the continent wide reflectivity (albedo) of the Greenland ice cap caused by increasing rates of surface melting which reach minima around 2014, 2015.

The high anomalous atmospheric methane contents recorded this year at Barrow Point Alaska (up to 2500 ppb - Carana 2012b) and the fact that the surface atmospheric methane contents may be linked via a stable partial pressure gradient with increased maximum methane contents in the world encompassing global warming veil (estimated at ca 1460 ppb methane) makes it imperative that the Merlin lidar satellite be launched as soon as is feasibly possible. The Merlin lidar satellite will give us a clear idea of how high the Earth’s stratospheric methane concentrations are in this poorly documented giant methane reservoir formed above the ozone layer at 30 km to 50 km altitude (Ehret, 2010).

Methane detecting Lidar instruments could also be installed immediately on the International Space Station to give early warning of the methane buildup in the stratosphere and act as a back up in case the Merlin satellite fails.

Unless immediate and concerted action is taken by governments and oil companies to depressurize the Arctic subsea methane reserves by extracting the methane, liquefying it and selling it as a green house gas energy source, rising sea levels will breach the Thames Barrier by 2029 flooding London. The base of the Washington Monument (D.C.) will be inundated by 2031. Total global deglaciation will finally cause the sea level to rise up the lower 35% of the Washington Monument by 2051 (68.3 m or 224 feet above present sea level).


Saturday, August 11, 2012

Huge cyclone batters Arctic sea ice

The image below shows an unusually large and powerful cyclone that was churning over the Arctic in early August 2012. Two smaller systems merged on August 5 to form the storm, which at the time occupied much of the Beaufort-Chukchi Sea and Canadian Basin, reports NASA Earth Observatory. On average, Arctic cyclones last about 40 hours; as of August 9, 2012, this storm had lasted more than five days.

This cyclone’s central sea level pressure reached about 964 millibars on August 6, 2012—a number that puts it within the lowest 3% of all minimum daily sea level pressures recorded north of 70 degrees latitude, noted Stephen Vavrus, an atmospheric scientist based at the University of Wisconsin.

Image by By NASA Goddard Photo and Video
NASA’s Aqua satellite captured above natural-color mosaic image on August 6, 2012. The center of the storm at that date was located in the middle of the Arctic Ocean.

The combined screenshots (6 & 8 August) below from Oceanweather Inc give an idea of size of the waves churned up by the cyclone.


The storm came in from Siberia, intensified and then positioned itself over the central Arctic, engendering 20 knot winds and 50 mph wind gusts, reports Skeptical Science.

The Arctic Sea Ice Blog covered the unfolding events well, in a series of posts including:
Many excellent comments were also added underneath these posts, e.g. by Steve Coulter who noted that "when fragmented floes are present, each irregular piece of ice acts as a sail in the wind, so the wind transfers momentum more readily to the surface. And each piece of ice, being 90% submerged, quite effectively transfers that momentum to the water. With winds moving in essentially a single direction in any given area, vast volumes of surface water are more readily put into motion. The difference in motion between the surface and deep water inevitably creates mixing."

Such mixing could mean that sediments that have been frozen until now get exposed to warmer water. This could destabilize methane contained in such sediments, either in the form of free gas or hydrates.

John Nissen, Chair of the Arctic Methane Emergency Group (AMEG), comments:
"There are at least three positive feedbacks working together to reinforce one another - and now a fourth on salinity:
  1. The albedo flip effect as sea ice is replaced by open water absorbing more sunlight, warming and melting more sea ice.
  2. As the sea ice gets very thin, it is liable to break up easily and get blown into open water where it will melt more easily.
  3. The open warmer water is allowing increased strength of storms, which break up the ice to make for more open water.
  4. The storms are churning up the sea to a depth of 500 metres, producing salinity at the surface that will mean slower ice formation in winter and more open water next year.
These feedbacks are dangerous for methane. AMEG has been warning that, as the sea ice retreats, storms will warm the sea bed, leading to further release of methane. In ESAS, we only need mixing to a depth of 50 metres - so a storm capable of mixing to 500 metres will really stir things up.

These feedbacks are also dangerous for food security, already damaged through climate extremes induced by Arctic warming, hence our piece in the Huffington Post.

The only way to head off catastrophe is to cool the Arctic, which must involve geoengineering as quickly as possible. We must try to remain positive and determined about this, despite the gloomy news."


Above image shows a retreat in sea ice area to 3.15521 million km2 on the 221st day of 2012, down from 3.91533 million km2 on the 212th day of 2012, from The Cryosphere Today.

The 30-days animation below, from the Naval Research Laboratory, show the recent ice speed and drift.



The 30-days animation below, also from the Naval Research Laboratory, show recent decline of the thickness of the sea ice.  


Friday, August 10, 2012

Sea ice in the Arctic - Shaken and stirred (by a powerful cyclone)

By Paul Beckwith


From my chair, it looks to me like there will be zero sea ice in the Arctic by September 30th of this year 2012.

The massive cyclone in the Arctic of unprecedented size has been chewing up the sea ice for the last week and it looks like over 1 million square km has been lost. A few more cyclones there will finish it off completely.

My presentation on the link below needs polishing, is quite technical in places and is mostly my compilation of blogs and data and comments from other scientists, engineers, and lay-people. It is mostly in chronological order as the storm has progressed.

Sea ice in the Arctic - Shaken and stirred (by a powerful cyclone)
August 3 to 10, 2012, by Paul Beckwith

https://docs.google.com/open?id=0B7jFQnAaMpkXVFNLRUhXUmdaWk0