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Signs of rapid arctic warming since 2000
by Brent Herbert
Saturday October 08, 2005 at 11:49 AM
The next few decades should be really "interesting".
 cretaceous.jpg, image/jpeg, 300x197
According to statements released by the National Snow and Ice Data Center (NSIDC) in Boulder, Colorado, acceleration of melting in the arctic has caused scientists studying the phenomena to revise their estimates of the effect of climate change in the arctic. Previously it was typical to estimate that the arctic would be ice free by the year 2100, but the new data would suggest that the process may be complete by the year 2060. According to NSIDC, "September 2005 will set a new record minimum in the amount of Arctic sea ice cover. It's the least sea ice we've seen in the satellite record, and continues a pattern of extreme low extents of sea ice which we've now seen for the last four years."
This increasingly rapid melting can best be seen in an animation produced by NASA which shows the shrinking of the year round ice cap since 1979. At the very end of the animation, the drop in the size of the of the ice cap is much more dramatic, and this has caused discussion on the subject of 'feedback loops'. Concurrent with this change is a rapid drop in the thickness of the ice sheet, which also facilitates melting, as well as an increase in the melting season.
An mpeg video graphically displays this sudden decline since 2000. http://www.nasa.gov/centers/goddard/mpg/97515main_SeaIceYrly.mpg
Ice reflects light and heat back out into space, but water absorbs and holds heat, so that as ice melts, the process can accelerate as more water surface is exposed, trapping more heat, and leading to more melting. Based on the more rapid melting taking place in the arctic, the year '2060' is now being mentioned as the time when the arctic will be ice free during the summer months.
Up until the 1990s it was believed that global climate change processes took place over long time scales, involving centuries, or even thousands of years, in a process of gradual and continuous change. However since that time it has been found by studying ice and sediment cores that sudden and very rapid climate change has taken place in the past in as little as ten years.
In this way the climate seems to resemble a system with 'thresholds', such as is the case with certain chemical reactions, wherein not much happens until a required amount of a certain chemical is introduced, at which time explosive change occurs.
According to Climate Change 2001:Working Group II http://www.grida.no/climate/ipcc_tar/wg2/061.htm "Strongly nonlinear responses are characterized by thresholds—which, if exceeded by a stimulus, result in substantially greater sensitivity to further stimulus or dramatic change, explosive growth, or collapse. Complex responses involve interactions of many intricate elements that yield outcomes that are not easily predicted...Omission of potential nonlinear and complex responses from climate change impact assessments is expected to yield underestimates of impacts."
This non-linearity is not captured by many climate modeling computer programs, which continue to predict a smooth linear change in the climate, and thus fail to encapsulate the evidence from the past of the climate reacting suddenly and swinging immediately into a new state in a very short time.
http://unisci.com/stories/20014/1214011.htm "Past climates changed abruptly, suggesting that abrupt changes in the future will also occur, according to a Penn State geoscientist. “When we look at records of the past, climate often changed abruptly rather than smoothly,” says Dr. Richard B. Alley, the Evan Pugh professor of geosciences at Penn State. “This is true wherever and whenever you look.” ... Alley, who is currently chairing the National Academy of Science Committee on Abrupt Climate Change: Science and Public Policy, told attendees Thursday (Dec. 13) at the fall meeting of the American Geophysical Association in San Francisco, that while studies of ice cores, sediments and other relics of the past indicate these abrupt changes, the models currently used by those predicting the future of climate change do not do a good job of simulating abrupt changes in the past ... In the long term, abrupt change appears to be the norm. Current models all tend to change smoothly and do not capture abruptness ... The Penn State geoscientist suggests that climate change includes a process of approaching and crossing a series of thresholds...With climate, the thresholds in the past have sometimes been reached in as few as 10 years ... Any reality may be very different from the predictions and we need to anticipate changes and surprises."
It is worth noting here that scientists are using 'moderate' figures for the amount of greenhouse gases are likely to be released to model the changes in the coming decades. However, at the same time that the arctic ice cap is melting, the permafrost is melting as well, with the large melt in Siberia taking place just over the last four years, as well, concurrent with that more rapid melting of the arctic ice cap, which is noticeable on the video linked to above.
According to New Scientist Magazine, http://www.newscientist.com/article.ns?id=mg18725124.500 "THE world's largest frozen peat bog is melting. An area stretching for a million square kilometres across the permafrost of western Siberia is turning into a mass of shallow lakes as the ground melts..(this) could unleash billions of tonnes of methane, a potent greenhouse gas, into the atmosphere...the entire western Siberian sub-Arctic region has begun to melt, and this "has all happened in the last three or four years". ... Kirpotin suspects that some unknown critical threshold has been crossed, triggering the melting...Similar warming has also been taking place in Alaska: earlier this summer Jon Pelletier of the University of Arizona in Tucson reported a major expansion of lakes on the North Slope fringing the Arctic Ocean...Methane is 20 times as potent a greenhouse gas as carbon dioxide...(there are) methane hotspots in eastern Siberia, where the gas was bubbling from thawing permafrost so fast it was preventing the surface from freezing, even in the midst of winter. An international research partnership known as the Global Carbon Project earlier this year identified melting permafrost as a major source of feedbacks that could accelerate climate change by releasing greenhouse gases into the atmosphere."
Other related changes that have been taking place include the melting of the world's glaciers, with the problem being particularly acute in South America where millions of people rely exclusively on the run off from disappearing glaciers for drinking water, with the problem predicted to become critical as soon as 2020.
It is also worth noting that only 6000 years ago, when the climate was only about a degree or two warmer than in the intervening centuries, the Sahara desert consisted of savannah and swamps, and computer models predict that concurrent with warming in the arctic there will be a return of rainfall to the Sahara desert. This would make the Sahara into a signal environment, a canary in the coal mine, and one would be able to use such a change to raise public awareness of the reality of climate change, since this desert has been a stable feature of the past climate regime for thousands of years. For this reason I have been following with interest the progress of one really big storm over the Sahara, and two smaller storms over the past couple of weeks, with the idea being that sooner or later it has to happen, thus establishing the most dramatic signal indicator of climate change (although that melting of the polar ice cap and Siberia are pretty convincing in and of themselves, a lot more menacing, given all that methane and all that frozen water).
Archimedes principle dictates that any object in water already displaces an amount of water equal to its own mass. Therefore, since most of the melting of the arctic ice cap is currently taking place on the floating ice sheets, it is possible for this process to continue without raising a lot of public alarm because the melting of floating ice sheets will not raise the level of the oceans. The problem becomes more severe when ice on land begins to melt, and it is estimated that just the Greenland ice sheet alone has enough frozen water to raise ocean levels 21 feet. Just to give people some idea of how much water exists in a frozen state on this planet I include a graphic which shows the United States during the Cretaceous period, which was much warmer than today, and as you can see the country consisted of two islands, where the Rocky and Appalachian mountains are today, and the rest of the country was part of the ocean.
During the time period that the United States was under water, fossil finds indicate that the high north, in places like the Yukon and Alaska were covered with tropical forests, since the climate at the time was so warm that there was no arctic ice cap, a climate regime that we seem to be heading towards again during the present time. This conditions was created by a natural process referred to as the Paleocene-Eocene Thermal Maximum. What happened is that somehow there was a large release of methane into the atmosphere, and the climate went through a very sudden change. The temperature rose rapidly and all the ice on the planet melted and the far north became tropical. There was a great extinction event as the methane released into the atmosphere then degraded into carbon dioxide and turned the oceans into acid (another phenomenon that is happening now, and is causing the bleaching of coral reefs worldwide). The boundary in the ocean sediments which marks out the period of the Thermal Maximum is denoted by a layer of red clay, rather than the usual white calcium carbonate sediments, which was caused by the destruction of the shells of ocean creatures by the high acidic content of the oceans.
It is assumed that the methane responsible for this dramatic shift in the climate and this major extinction event was caused by warming of the oceans which then released frozen methane crystals which are prevelant in cold water sediments and also along the boundaries of continental margins. Therefore there are two possible sources for the rapid release of methane under the current conditons, the first being the melting permafrost of the arctic regions, which could then result in sufficient warming of the oceans to release even more methane currently frozen under high pressure in colder waters.
All of this is an attempt to point out to people just how much water exists on this planet in the form of frozen ice, and how it is in the best interests of everyone to see to it that it stays frozen. The decades between now and 2060 will be quite 'interesting' (or perhaps even sooner and with even more suddenness, given the potential for self reinforcing feedback loops to rapidly accelerate these processes, as has happened in the past history of the climate). Worst of all will be all the hysteria that kicks in once that ice on land starts melting. It has been said that 'a free market' has the answer to everything, but even more outrageous is how those big oil multinationals kept buying up the patents to alternative energy sources and then sat on them, a fine example of the type of short term self interest that really characterizes this out of control system of exploitation that we currently live under, where no rational decisions can ever be made, but rather decisions are made to protect the narrow interests of cliques of investors in some market.
There are solutions, but they will not be found in some 'market'. As people might recall, such technologies as microwave ovens, or the internet, were not developed by some market, but rather they were developed by the government, and then markets were allowed to capitalize on the public investment. Given this general trend in past history, it seems very unlikely that some market will save the planet from global warming, especially when you consider how oil multinationals and big coal corporations have taken action to control the patents for alternative energy sources, thus making the further development of such sources 'illegal' since it would now infringe on the patents held by these monopolies.
Just three hundred square miles of the earth's surface receives enough solar radiation to replace all the other energy sources currently used on earth. It is obvious that the solution to energy problems on this planet lies in the sun, but this would not funnel huge profits into the wallets of cartels, since the sun is free, which would explain the lack of development in this area, and is just one more example of how markets do not work.
Currently solar technology relies on silicon, which at best is about 6 or 7 percent efficient, and expensive. However better technology already exists in nature in the form of phosphors, which are natural batteries, which absorb light energy and store it and then release it (thus causing this natural material to 'glow in the dark'). It is obvious to me that what we have here is a solar collector which is also a natural battery, and the future (assuming that we have a future aside from 'neo-liberalism', and therefore everyone is not destined to drown in their attic or starve to death) lies with solar energy developed not from silicon but rather from phosphors. It is also obvious that all changes coming up mark the end of the age of that neo-liberal capitalism and its out of control agenda which if it is not already discredited by doing such things as sending all those jobs of Americans to sweat shops in the third world, should certainly pound the final nails into its coffin by either almost destroying the planet, or completely destroying the planet, just depending on how everything works out in the coming years.
www.awitness.org/
Sahara Storm Sept 27-29
by Brent Herbert
Saturday October 08, 2005 at 11:49 AM
 sahsept27.jpg, image/jpeg, 300x208
www.awitness.org/
Thanks
by martin
Saturday October 08, 2005 at 03:23 PM
nimfm@nimfm.org
Thank you for this story. It persuaded me to pick up on it for my community radio program. I hope you don't mind - it is non-profit! You will be fully credited on air - and your internet links/e-mail sites will be mentioned at the end of the program - o.k? Write to me if you disagree - we will not air anything, which has not been authorized. martin e-mail: nimfm@nimfm.org
nimbinradiomedia.libsyn.com
rare hurricane in the north atlantic
by brent
Tuesday October 11, 2005 at 02:11 AM
 tradwinds.gif, image/gif, 300x300
The real media file shows Hurricane Vincent which formed this weekend off the North Coast of Africa. It is a very small hurricane, only about 100 kilometers in size, and is situated in the center top of the video image, where you can see it spinning up and notice a very tiny circular eye wall.
What is very unusual about Vincent is that it formed in water that is only about 23 degrees celsius (or about 75 Farenheit) and normally a hurricane cannot form unless the water is at a minimum of 27 C (or about 80 F). Another unusual feature seen at the same time as Vincent was forming is the unusual air flow on the Sahara concurrent with this hurricane. Normally the tradewinds (at the bottom of the video) move from Africa to South America. You can see lines on the graphic showing the convergence of the winds coming down off the Sahara and up from the equator to head westward. However on the video you can see that there is little Eastward motion visible in the Trade Winds, but instead there is a circulation moving up the western Sahara and then accross the top of the Desert, which seems to be pulling up moisture from what would normally be the Westward moving trade winds.
Hurricane Vincent has dropped down to a wind speed of 70 mph, which is 5 mph below hurricane one catagory, and is now being referred to as 'Tropical Storm Vincent' and on the video appears to be steered eastward towards the Northern African coast.
Vincent Real media
by brent
Tuesday October 11, 2005 at 02:12 AM
RealVideo: stream with RealPlayer or download RM file (81.7 kibibytes)
video
Landfall
by brent
Tuesday October 11, 2005 at 09:18 AM
 vince.jpg, image/jpeg, 141x114
A correction...The name of this hurricane was Vince (not vincent) In the image, just below the red line, you can see Tropical storm vince just a few hours before it made landfall on the North African coast. You can still make out the tiny eye wall in the center of the storm.
younger dryas
by brent
Tuesday October 11, 2005 at 07:43 PM
 methane.jpg, image/jpeg, 400x270
The younger dryas occured sometime around 12,000 years ago, when the large ice sheets of the last ice age halted the melting process for about 1,000 years, with the change going into the period and coming out of the period taking place in the span of around a decade, according to ice core samples, which demonstrates how the climate responds in a non-linear way. However comparisons made between the younger dryas and today and not really applicable, since the world was still covered by massive ice sheets at that time, a condition which does not exist today, making some kind of direct comparison between that phenomena and today's climate unreasonable...
according to what I have read, what is believed to have happened is that the Laurentian ice sheet broke apart, much like the Ward Hunt Ice sheet on Ellesmere Island broke apart two years ago, and this break up allowed a trapped Lake of cold fresh water to suddenly flood out of the center of the ice sheet, carving the St Laurence river system in the process (hence the name) and introducing large amounts of fresh water in the North Atlantic at the same time...
As much as fifty percent of the winter heat in places like Europe of the East Coast of the United States comes not from solar radiation but rather from heat released by the Atlantic Conveyer Belt, so the disruption caused to the ocean currents by this event then caused sufficient loss of warming from the tropics to halt the deglaciation...but remember, this was a period of deglaciation to begin with, and so trying to make some kind of comparison between the Younger Dryas and the modern world is like comparing apples and oranges...
One of the most significant variables today would probably be the billions of tons of methane which could be in the process of being released into the atmosphere by processes such as the now ongoing melting of Siberia, with a similar process seeming to in process in the Tundra areas of North America as well...the last time such large amounts of methane were released into the atmosphere all at once took place during the Thermal Maximum, about 55 million years agom and resulted in rapid global warming...this would be what you would expect when you wrap the earth in a blanket...not glaciation, or global cooling, but rather global warming...
The graph, from IPCC site shows the increase in methane in the atmosphere which rises sharply over the last century and a half...as you can see by the graphic of a farm with silos and a cow in the bottom right corner, this rise in methane is attributed to large scale livestock production...however even this sharp rise in methane levels cannot compare to the amount of methane that could be released by the melting of the permafrost in the frozen bogs of the high north. For comparison purposes, the United States releases about 6 million tons of methane into the atmosphere from livestock operations (mainly cattle) each year, while globally total human related methane release totals 30 million tons. Just the melting of western Siberia has the potential to release up to an estimated 70 billion tons of methane, which is on a scale of about 2,000 times more methane than the total annual anthropogenic forcing introduced currently by human processes. Such a large release of methane naturally then invalidates the conventional climate models which are based on moderate releases of greenhouse gases and predict relatively smooth and linear changes, and such moderate impacts as 'no sea ice in the arctic by 2100' when what we could actually be seeing is rapid climate, and no ice in the polar regions at all, and all this even before 2100.
of course all this is 'alarmist', but given how the 'moderate' scenarios do not seem to inspire people to take matters all that seriously, maybe a little bit of alarmist rhetoric is called for, especially when recent events would suggest that what is 'alarmist; might actually be what is realistic, while what is 'moderate' is actually dangerously over optimistic.
The IPCC methane graphic is found here http://www.ipcc.ch/present/graphics/2001wg1/large/02.02.jpg and links to other IPCC graphics are found here http://www.ipcc.ch/present/graphics.htm
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