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Senin, 07 April 2014

Permafrost thawing could accelerate global warming


"If the permafrost melts entirely, there would be 5x the amount of carbon in the atmosphere than there is now" - Jeff Chanton

Jeff Chanton, the John Widmer
Winchester Professor of
Oceanography at Florida State.
A team of researchers lead by Florida State University have found new evidence that permafrost thawing is releasing large quantities of greenhouse gases into the atmosphere via plants, which could accelerate warming trends.

The research is featured in the newest edition of the Proceedings of the National Academy of Sciences.

“We’ve known for a while now that permafrost is thawing,” said Suzanne Hodgkins, the lead author on the paper and a doctoral student in chemical oceanography at Florida State. “But what we’ve found is that the associated changes in plant community composition in the polar regions could lead to way more carbon being released into the atmosphere as methane.”

Permafrost is soil that is frozen year round and is typically located in polar regions. As the world has gotten slightly warmer, that permafrost is thawing and decomposing, which is producing increased amounts of methane.

Relative to carbon dioxide, methane has a disproportionately large global warming potential. Methane is 33 times more effective at warming the Earth on a mass basis and a century time scale relative to carbon dioxide.

Changes in plant community composition in the polar regions could lead to way more carbon being released into the atmosphere as methane

As the plants break down, they are releasing carbon into the atmosphere. And if the permafrost melts entirely, there would be five times the amount of carbon in the atmosphere than there is now, said Jeff Chanton, the John Widmer Winchester Professor of Oceanography at Florida State.

“The world is getting warmer, and the additional release of gas would only add to our problems,” he said.

Chanton and Hodgkins’ work, “Changes in peat chemistry associated with permafrost thaw increase greenhouse gas production,” was funded by a three-year, $400,000 Department of Energy grant. They traveled to Sweden multiple times to collect soil samples for the study.

The research is a multicontinent effort with researchers from North America, Europe and Australia all contributing to the work.



References

- Permafrost thawing could accelerate global warming - Florida State University news release
http://news.fsu.edu/More-FSU-News/Permafrost-thawing-could-accelerate-global-warming

- Changes in peat chemistry associated with permafrost thaw increase greenhouse gas production

Senin, 28 Oktober 2013

How Do We Act in the Face of Climate Chaos?

Guy McPherson


Guy R. McPherson is Professor Emeritus of Natural Resources
and 
Ecology & Evolutionary Biology at University of Arizona.
Below are some (slighly edited) extracts from a post at Guy
McPherson's website: 
summary and update on climate change.




The Warning

As described by the United Nations Advisory Group on Greenhouse Gases in 1990, temperature rise “beyond 1 degree C may elicit rapid, unpredictable and non-linear responses that could lead to extensive ecosystem damage”.

We’ve clearly triggered the types of positive feedbacks the United Nations warned about in 1990. Yet my colleagues and acquaintances think we can and will work our way out of this horrific mess with permaculture (which is not to denigrate permaculture, the principles of which are implemented at the mud hut). Reforestation doesn’t come close to overcoming combustion of fossil fuels, as pointed out in the 30 May 2013 issue of Nature Climate Change. Furthermore, forested ecosystems do not sequester additional carbon dioxide as it increases in the atmosphere, as disappointingly explained in the 6 August 2013 issue of New Phytologist.

Here’s the bottom line: On a planet 4 C hotter than baseline, all we can prepare for is human extinction (from Oliver Tickell’s 2008 synthesis in the Guardian).

John Davies concludes: “The world is probably at the start of a runaway Greenhouse Event which will end most human life on Earth before 2040.” He considers only atmospheric carbon dioxide concentration, not the many self-reinforcing feedback loops described below. 


Positive feedbacks
Positive feedbacks
Methane hydrates are bubbling out the Arctic Ocean (Science, March 2010). According to NASA’s CARVE project, these plumes were up to 150 kilometers across as of mid-July 2013. Whereas Malcolm Light’s 9 February 2012 forecast of extinction of all life on Earth by the middle of this century appears premature because his conclusion of exponential methane release during summer 2011 was based on data subsequently revised and smoothed by U.S. government agencies, subsequent information — most notably from NASA’s CARVE project — indicates the grave potential for catastrophic release of methane. Catastrophically rapid release of methane in the Arctic is further supported by Nafeez Ahmed’s thorough analysis in the 5 August 2013 issue of the Guardian as well as Natalia Shakhova’s 29 July 2013 interview with Nick Breeze (note the look of abject despair at the eight-minute mark).
Warm Atlantic water is defrosting the Arctic as it shoots through the Fram Strait (Science, January 2011).
Siberian methane vents have increased in size from less than a meter across in the summer of 2010 to about a kilometer across in 2011 (Tellus, February 2011)
Drought in the Amazon triggered the release of more carbon than the United States in 2010 (Science, February 2011). In addition, ongoing deforestation in the region is driving declines in precipitation at a rate much faster than long thought, as reported in the 19 July 2013 issue of Geophysical Research Letters.
Peat in the world’s boreal forests is decomposing at an astonishing rate (Nature Communications, November 2011)
Invasion of tall shrubs warms the soil, hence destabilizes the permafrost (Environmental Research Letters, March 2012)
Methane is being released from the Antarctic, too (Nature, August 2012). According to a paper in the 24 July 2013 issue of Scientific Reports, melt rate in the Antarctic has caught up to the Arctic.
Russian forest and bog fires are growing (NASA, August 2012), a phenomenon consequently apparent throughout the northern hemisphere (Nature Communications, July 2013). The New York Times reports hotter, drier conditions leading to huge fires in western North America as the “new normal” in their 1 July 2013 issue. A paper in the 22 July 2013 issue of the Proceedings of the National Academy of Sciences indicates boreal forests are burning at a rate exceeding that of the last 10,000 years.
Cracking of glaciers accelerates in the presence of increased carbon dioxide(Journal of Physics D: Applied Physics, October 2012)
The microbes have joined the party, too, according to a paper in the 23 February 2013 issue of New Scientist
Summer ice melt in Antarctica is at its highest level in a thousand years: Summer ice in the Antarctic is melting 10 times quicker than it was 600 years ago, with the most rapid melt occurring in the last 50 years (Nature Geoscience, April 2013). Although scientists have long expressed concern about the instability of the West Atlantic Ice Sheet (WAIS), a research paper published in the 28 August 2013 of Nature indicates the East Atlantic Ice Sheet (EAIS) has undergone rapid changes in the past five decades. The latter is the world’s largest ice sheet and was previously thought to be at little risk from climate change. But it has undergone rapid changes in the past five decades, signaling a potential threat to global sea levels. The EAIS holds enough water to raise sea levels more than 50 meters.
Surface meltwater draining through cracks in an ice sheet can warm the sheet from the inside, softening the ice and letting it flow faster, according to a study accepted for publication in the Journal of Geophysical Research: Earth Surface (July 2013). It appears a Heinrich Event has been triggered in Greenland. Consider the description of such an event as provided by Robert Scribbler on 8 August 2013:
In a Heinrich Event, the melt forces eventually reach a tipping point. The warmer water has greatly softened the ice sheet. Floods of water flow out beneath the ice. Ice ponds grow into great lakes that may spill out both over top of the ice and underneath it. Large ice damns (sic) may or may not start to form. All through this time ice motion and melt is accelerating. Finally, a major tipping point is reached and in a single large event or ongoing series of such events, a massive surge of water and ice flush outward as the ice sheet enters an entirely chaotic state. Tsunamis of melt water rush out bearing their vast floatillas (sic) of ice burgs (sic), greatly contributing to sea level rise. And that’s when the weather really starts to get nasty. In the case of Greenland, the firing line for such events is the entire North Atlantic and, ultimately the Northern Hemisphere.
Breakdown of the thermohaline conveyor belt is happening in the Antarctic as well as the Arctic, thus leading to melting of Antarctic permafrost (Scientific Reports, July 2013)
Loss of Arctic sea ice is reducing the temperature gradient between the poles and the equator, thus causing the jet stream to slow and meander. One result is the creation of weather blocks such as the recent very high temperatures in Alaska. As aresultboreal peat dries and catches fire like a coal seam. The resulting soot enters the atmosphere to fall again, coating the ice surface elsewhere, thus reducing albedo and hastening the melting of ice. Each of these individual phenomena has been reported, albeit rarely, but to my knowledge the dots have not been connected beyond this space. The inability or unwillingness of the media to connect two dots is not surprising, and has been routinely reported (recently including here with respect to climate change and wildfires) (July 2013)
Earthquakes trigger methane release, and consequent warming of the planet triggers earthquakes, as reported by Sam Carana at Arctic-news (October 2013)
Arctic drilling was fast-tracked by the Obama administration during the summer of 2012
Supertankers are taking advantage of the slushy Arctic, demonstrating that every catastrophe represents a business opportunity, as pointed out by Professor of journalism Michael I. Niman and picked up by Truthout (ArtVoice, September 2013)
As nearly as I can distinguish, only the latter feedback process is reversible at a temporal scale relevant to our species. Once you pull the tab on the can of beer, there’s no keeping the carbon dioxide from bubbling up and out. These feedbacks are not additive, they are multiplicative. Now that we’ve entered the era of expensive oil, I can’t imagine we’ll voluntarily terminate the process of drilling for oil and gas in the Arctic (or anywhere else). Nor will we willingly forgo a few dollars by failing to take advantage of the long-sought Northwest Passage.

Robin Westenra provides an assessment of these positive feedbacks at Seemorerocks on 14 July 2013. It’s worth a look.


Earth-system scientist Clive Hamilton concludes in his April 2013 book Earthmasters that “without [atmospheric sulphates associated with industrial activity] … Earth would be an extra 1.1 C warmer.” In other words, collapse takes us directly to 2 C within a matter of weeks. 

Several other academic scientists have concluded, in the refereed journal literature no less, that the 2 C mark is essentially impossible (for example, see the review paper by Mark New and colleagues published in the 29 November 2010 issue of the Philosophical Transactions of the Royal Society A). 

The German Institute for International and Security Affairs concluded 2 June 2013 that a 2 C rise in global-average temperature is no longer feasible (and Spiegel agrees, finally, in their 7 June 2013 issue), while the ultra-conservative International Energy Agency concludes that, “coal will nearly overtake oil as the dominant energy source by 2017 … without a major shift away from coal, average global temperatures could rise by 6 degrees Celsius by 2050, leading to devastating climate change.” 

Image from: The two epochs of Marcott, by Jos Hagelaars

At the 11:20 mark of this video, climate scientist Paul Beckwith indicates Earth could warm by 6 C within a decade. 

If you think his view is extreme, consider: 
  1. the 5 C rise in global-average temperature 55 million years ago during a span of 13 years (reported in the 1 October 2013 issue of Proceedings of the National Academy of Sciences); and also 
  2. the reconstruction of regional and global temperature for the past 11,300 years published in Science in March 2013. One result is shown in the above figure.

How Do We Act in the Face of Climate Chaos?

Below is a video of a recent presentation by Guy McPherson. 

Presentation by Guy McPherson in Boulder, Colorado on October 16, 2013.

Below are some extracts from the video, again slightly edited.

Malcolm Light in 2012 concluded, based on data from NOAA and NASA, that methane release had gone exponential and was leading to the demise of all life on Earth, not just human extinction, by the middle of the century.

So 3.5 C to 4 C is almost certainly a death sentence for all human beings on the planet, not because it'll be a warmer planet, but because the warming of the planet will remove all habitat for human beings. Ultimately we're human animals like other animals, we need habitat to survive.

Changes we see in three or four decades happen as a result of what we do today. There's a huge lag between our actions today in the consequences down the road in terms of the Earth's planetary systems.

Without plankton in the ocean, there goes roughly half the global food supply. The ability to lose land plants is growing rapidly and there goes the other half for the food supply for human beings. If we have up to 5 C by 2050, that'll certainly do the trick.

Why is this happening? It's civilization that drove us into population overshoot. We cannot go back anymore since 1939, since we invented nuclear armageddon. There's no going back. If we ceased the set of living arrangements at this point, the world's 400 or so nuclear power plants melt down catastrophically and we're all dead in a month. We cannot terminate industrial civilization until we decommission all nuclear power plants. It takes at least 20 years to decommission a nuclear power plant.

The bad news is that means that the world's four hundred or so nuclear power plants meltdown catastrophically in a short period of time. Fukushima represent a major threat to humanity. If they fail in moving the spent fuel rods next month, according to nuclear researcher Christina Consola, if one of those MOX fuel rods is exposed to the air, one of the 1565, it will kill 2.89 billion people on the planet in a matter of weeks, so nuclear catastrophe is right there on the horizon. 

People ask me: Why are you presenting this horrible information?

Action is the antidote to despair even if the action is hopeless. When a medical doctor knows that somebody has cancer, it's malpractice if they don't tell that. So I'm doing that. I think Bill McKibben and James Hansen and a whole bunch of climate scientists are guilty of malpractice. Because they know what I know. Almost every politician in the country knows what I know. All the leaders of the big banks know what I know. And they're lying to us.

I'm just presenting the information from other scientists here. I'm trying to the widest extent possible not to infuse my opinion in the situation. It's John Davies who on September 20, 2013, taking into account only carbon dioxide, says there will be few people left on the planet by 2040. It's Malcolm Light, writing in February 2012, who assesses the methane situation. And so on.

Yes, I agree with them, and that agreement is illustrated by me showing you that information.

I promote resistance against this omnicidal culture, not in the hope that it will save our species, but in the hope that it will save other species. Because as E.O. Wilson, biologist at Harvard, points out, it only takes 10 million years after a great extinction event, before you have a blossoming full rich planet again. That's what we're working toward. We're saving habitat for other species at this point.


Minggu, 15 September 2013

Colorado flooding, what does the IPCC say?

Flooding in Colorado has caused at least five death. As of 14 September, more than 500 were unaccounted for. Nearly 19,000 homes are damaged or destroyed.

Paul Beckwith comments:

Total destruction. Roads. Homes. Power lines. Water pipelines. Sewer culverts and pipes. And an oil pipeline. Not to mention the lives lost and disrupted forever.

Just be glad that the oil pipeline was not something like Keystone XL or Line 9 or Line 6.

Wake up people. Isn't it ironic that extreme weather events are accelerating in frequency, magnitude, spatial extent, and duration and are due to the very abrupt climate change that is being rapidly worsened from fossil fuel emissions; from burning the very stuff that is carried by the oil pipeline infrastructure.

And politicians are either very stupid or simply slaves to the fossil fuel companies since they ignore all laws protecting the environment, and even rewrite the legal system to eliminate any laws that slow or prevent pipelines, tar sands, fracking and any other fossil fuel infrastructure from being built. While publishing outright lies slamming renewable energy.

No wonder police forces across the world are becoming branches of the military; they realize that the public will soon be furious at the politicians and corporations and government corruption at all levels.

Meanwhile, according to the dailymail leaked IPCC reports say that "Global warming is just HALF what we said". So, what's going on? For starters, it appears that the IPCC has been fooled into ignoring the dangerous situation in the Arctic, i.e. albedo changes, methane and further feedbacks. The cartoon below illustrates this, please comment and share widely! 



Rabu, 04 September 2013

Existential risks to our planetary life-support systems

By Andrew Glikson

Figure 1. The future of Earth’s living environment is a non-issue in the current
Australian election - NASA image: Earth rising over the Moon
“We’re simply talking about the very life support system of this planet.”– Hans Joachim Schellnhuber, chief climate advisor to the German Government
It is not news that we are over stretching our planetary support systems: we have known for some time. In a 2009 keynote paper in Nature titled “A safe operating space for humanity”, a group of 26 prominent scientists showed three of nine interlinked planetary boundaries – boundaries we must stay within to keep Earth safe – have already been overstepped (see figure 2. below).

Those boundaries include:
  • climate change
  • biodiversity loss
  • the biogeochemical cycles.

Kevin Trenberth, chief scientist of the National Center for Atmospheric Research in Boulder, Colorado, states:
“Some of the human-induced changes are occurring 100-times faster than they occur in nature … And this is one of the things that worries me more than climate change itself. It’s actually the rate of change that’s most worrying … Ecosystems are not prepared for this jolt … And neither are many human endeavours, built around assumptions about how hot it’s going to be, how much it’s going to rain on our croplands, and how high the seas will rise.”

Figure 2. Planetary boundaries - the colored star-like area represents the estimated current state and the corners of the red octagon circumscribed by the Earth are the estimated boundaries. Systems whose safe operating space could not yet be determined were left out. Image from: Wikipedia / A safe operating space for humanity, Rockström et al, 2009.

This observation is dramatically demonstrated by the current rise of atmospheric greenhouse gases: this is at an unprecedented rate of 2 to 3 parts per million per year (see figure 3. below). This renders our era – the Anthropocene – a major oxidation event.

Such a growth rate of atmospheric greenhouse gases is extremely rare in geological history. The only analogue is the excavation of billions of tons of carbon from carbonate and shale formation hit by asteroids, such as the K-T impact 65 million years ago and massive global volcanic eruptions.

The consequences for the biosphere – the sixth mass extinction of species – threatens to become a tragedy for human ideals and for nature.

What or who is responsible for the unfolding calamity?

As defined, the Anthropocene is a new geological era triggered by a species which has uniquely mastered ignition. We are using it to excavate and release hundreds of billions of tons of carbon accumulated in Earth’s crust over geological eras into atmosphere.

Once a species masters sources of energy larger by orders of magnitude than its own physiological process (for Homo Sapiens this has been fire, electricity and nuclear fission), the species can hardly be expected to have the wisdom and degree of responsibility to stop its inventions from getting out of control.

Figure 3. Estimates of fossil fuel resources and equivalent atmospheric CO2 levels, including (1) emissions to date;
(2) estimated reserves, and (3) recoverable resources (1 ppm CO2 ~ 2.12 GtC). 
Hansen, 2012, figure 1; http://www.columbia.edu/~jeh1/mailings/2012/20120127_CowardsPart1.pdf
Unique among all species, humans adopted fire and combustion as their source of energy and power over nature. Over the last two million years, camped around fires, watching the flames, human imagination has grown to inquire, perceive future possibilities, develop fears, the craving for immortality, and the concept of gods. Fire has imparted a mythological quality to the human mind.

Once a stable climate was established in the Holocene (about 10,000 years ago), allowing cultivation and production of surplus food, this craving for omnipotence and omniscience was expressed by the building of monuments to immortality, the pyramids, as well as endless wars acquiring loot for this purpose.

Spiritual pantheism by pre-historic people such as the Australian Aboriginals has been transformed into admiration of sky gods and monotheism, then into crass materialism and the space cult.

But space exploration has taught us no other planet exists in the solar system on which the conditions exist for advanced life of the type hosted by Earth.

Since the greenhouse effect and its underlying laws of physics and chemistry were decoded in the 19th century, the question has arisen: to what extent will societies and their leaders accept the implications of the science for human industry and human future? Will the scientific method itself and the enlightenment form the basis of future decisions?

In 21st century Australia, the answer has been a resounding “no”.

Government and corporate decisions on climate change are being influenced by misrepresentations of the evidence. What began some 20 years ago as demonstration of solid empirical evidence has deteriorated to media-controlled debate replete with misunderstandings of the basic laws of physics, paleo-climate science, climate science, biological and ecological principles.

Figure 4. Relations between CO2 rise rates and mean global temperature rise rates during warming periods,
including the Paleocene-Eocene Thermal Maximum, Oligocene, Miocene, late Pliocene, Eemian (glacial termination),
Dansgaard-Oeschger cycles, Medieval Warming Period, 1750-2012 and 1975-2012 periods.
A multitude of media outlets and hundreds of websites proliferate notions ignorant of peer-reviewed science. The lesson of numerous attempted debates with those who deny the reality of global warming, or attempt to attribute it to natural non-human factors, is that those entertaining these notions cannot be dissuaded by any amount of scientific evidence.

Climate change misconceptions include claims that:
  • temperature rise came before CO2 rise during the glacial terminations and that therefore the current rise of temperature is not the result of CO2 rise. However, the effects of CO2and temperature variations are intertwined. During the last ~400,000 years glacial eras were terminated by periods of intense solar activity, affecting decreased CO2 solubility in warming water and thereby a rise in CO2 levels of the atmosphere. By contrast climate developments since the 18th century, when there was negligible or no rise in solar energy hitting the earth, were triggered by the anthropogenic greenhouse effect of the release of 560 billion tonnes of carbon, consistent with the basic laws of physics.
  • global warming is a recovery from the Little Ice Age. However, the Little Ice Age was caused when sunspot activity nearly ceased between 1650 and 1700, depressing global temperatures by 0.2-0.3C relative to preceding periods. By contrast, global warming from about 1975 has tracked toward more than 1.5C over the continents relative to pre-industrial temperatures.
  • cosmic rays flux affects warming. However, a dominant solar effect on the climate since 1970 is ruled out by measurements of solar radiation. The incidence of cosmic rays, which oscillate reciprocally with the 11 years sunspot cycle, has been shown to have minor effects on cloud nucleation and has not varied significantly since the mid-20th century.
  • carbon dioxide is emitted mainly from volcanoes. However, according to the United States Geological Survey (2012), sub-aerial and sub-marine volcanism emits approximately 150–260 million tons of CO2 a year. Anthropogenic emissions total about 35 billion tons CO2 a year.
Meanwhile, the unthinkable consequences of 4 degrees Celsius and higher temperature rise on the terrestrial atmosphere-ocean system have already begun. We are seeing a series of extreme weather events, reflecting the rise in energy/temperature of the atmosphere-ocean system – the “new normal”.

Andrew Glikson
Does responsibility lie with vested interests and fossil fuel lobbies promoting carbon saturation of the atmosphere? Does it lie with media barons and their mouthpieces hijacking the information systems of democracies, or with cowardly political “leaders” – presiding over extensive demise of future generations? Or does responsibility lie with all of us, with the species?

Deceived by pseudoscientific misconceptions, Homo “sapiens” continues to march toward a cliff, taking much of nature with it.

Earlier published at The Conversation.

Kamis, 08 Agustus 2013

The Social Tipping Point



by Paul Beckwith

Abrupt Climate Change is happening today, big time!

Abrupt climate change. It is happening today, big time. The northern hemisphere atmospheric circulation system is doing its own thing, without the guidance of a stable jet stream. The jet stream is fractured into meandering and stuck streaked segments, which are hoovering up water vapor and directing it day after day to unlucky localized regions, depositing months or seasons worth of rain in only a few days, turning these locales into water worlds and trashing all infrastructure like houses, roads, train tracks and pipelines. Creating massive sinkholes and catastrophic landslides. And climate change is only getting warmed up.

In the Arctic methane is coming out of the thawing permafrost. Both on land and under the ocean on the sea floor. The Yedoma permafrost in Siberia is now belching out methane at greatly accelerated rates due to intense warming. The collapsing sea ice in the Arctic Ocean is exposing the open ocean to greatly increased solar absorption and turbulent mixing from wave action due to persistent cyclonic activity. Massive cyclonic activity will trash large portions of the sea ice if positioned to export broken ice via the Fram Strait.

We have lost our stable climate

What does it all mean? There is no new normal? Far from it. We have lost our stable climate. Likely permanently. Rates of change are greatly exceeding anything in the paleorecords. By at least 10x, and more likely >30x. We are heading to a much warmer world. The transition will be brutal for civilization.

Can we avoid this? Stop it? Probably not? At least with climate reality being suppressed by corporations and their government employees. With their relentless push for more and more fossil fuel infrastructure and mining and drilling.

What else can we expect as we negotiate our abrupt transition in climate to a much warmer world?

Craziness, in a nutshell. Temperatures over land surfaces in the far north have been consistently over 25 C for weeks, due to persistent high pressure atmospheric blocks leading to clear skies and unblocked solar exposure. Water temperatures in rivers and streams in the far north have resulted in large fish kills as their ecological mortality thresholds have been exceeded. Many other regions are experiencing strange incidences of animal mortality. Mass migrations of animals towards the poles are occurring on land and sea, at startling rates, in an effort for more hospitable surroundings for survival. Shifting food source distributions is causing even hardier, less vulnerable species to be severely stressed. For example, dolphins are being stranded or dying, birds are dropping out of the sky, and new parasites and bacteria are proliferating with warmer temperatures.

In regions of the world undergoing severe droughts the vegetation and soils are drying and fires are exploding in size, frequency, and severity. Especially hard-hit are large regions of the US southwest, southern Europe, and large swaths of Asia. Who knows if forests that are leveled by fire will eventually be reforested; it all depends on what type of climate establishes in the region.

What about coastal regions around the world and sea levels? Not looking too good for the home team. In 2012 Greenland tossed off about 700 Gt (Gt=billion tons) of sea ice, from both melting and calving. As the ice melts it is darkening from concentrated contaminants being exposed, from much greater areas of low albedo meltwater pools, and from fresh deposits of black carbon ash from northern forest fires. Even more worrying are ominous signs of increasing movement. GPS sensor anchored to the 3 km thick glaciers hundreds of km from the coast are registering increased sliding. Meltwater moulins are chewing through the ice from the surface to the bedrock and are transporting heat downward, softening up the ice bonded to the bedrock and allowing sliding. Eventually, large chunks will slide into the ocean causing tsunamis and abrupt sea level rises. Many regions of the sea floor around Greenland are scarred from enormous calving episodes in the past.

The Social Tipping Point

On a positive note, this knowledge of our changing climate threat is filtering out to greater numbers of the slumbering public that has been brainwashed into lethargy by the protectors of the status quo. As more and more people see the trees dying in their back yards and their cities and houses and roads buckling under unrelenting torrential rains they are awaking to the threat. And there will be a threshold crossed and a tipping point reached in human behavior. An understanding of the reality of the risks we face. And finally global concerted action. To slash emissions. And change our ways. And retool our economies and reset our priorities. And not take our planet for granted.



Paul Beckwith is a part-time professor with the laboratory for paleoclimatology and climatology, department of geography, University of Ottawa. He teaches second year climatology/meteorology. His PhD research topic is “Abrupt climate change in the past and present.” He holds an M.Sc. in laser physics and a B.Eng. in engineering physics and reached the rank of chess master in a previous life.


The above compilation of IPCC and NOAA images is by Peter Carter, who adds the following comment:
I agree. The IPCC in 2007 said: "The concentration of CO2 is now 379 parts per million (ppm) and methane is greater than 1,774 parts per billion (ppb), both very likely much higher than any time in at least 650 kyr (during which CO2 remained between 180 and 300 ppm and methane between 320 and 790 ppb). The recent rate of change is dramatic and unprecedented; increases in CO2 never exceeded 30 ppm in 1 kyr – yet now CO2 has risen by 30 ppm in just the last 17 years."

By definition this is abrupt heating. because atmospheric GHG concentration correlates directly with radiative forcing. CO2 is now 397 ppm and methane is now 1830 ppb ! It follows that the rate of ice being melted will also (as it looks) be unprecedented. The only force we have against mad fossil fuel pushing governments is accountability. They have to be made to face the full terrible consequences of their action on energy and inaction on climate. They are destroying the world.

Minggu, 04 Agustus 2013

Methane as high as 2349 ppb


Earth is undergoing one of the largest climate changes in the past 65 million years, Stanford climate scientists Noah Diffenbaugh and Chris Field report, and it's on pace to occur at a rate 10 times faster than any change in that period.

“We know from past changes that ecosystems have responded to a few degrees of global temperature change over thousands of years,” said Diffenbaugh. “But the unprecedented trajectory that we're on now is forcing that change to occur over decades.”

Some of the strongest evidence for how the global climate system responds to high levels of carbon dioxide comes from paleoclimate studies. Fifty-five million years ago, carbon dioxide in the atmosphere was elevated to a level comparable to today. The Arctic Ocean did not have ice in the summer, and nearby land was warm enough to support alligators and palm trees. But apart from the rate of change, Diffenbaugh adds, another key difference is that “today there are multiple human stressors that were not present 55 million years ago, such as urbanization and air and water pollution.”

By the end of the century, should the current emissions of greenhouse gases remain unchecked, temperatures over the northern hemisphere will tip 5-6 degrees C warmer than today's averages. In this case, the hottest summer of the last 20 years becomes the new annual norm.

The situation looks to be even more dire than that, argues Sam Carana. In addition to carbon dioxide, there are further pollutants driving global warming. Moreover, as pictured below, feedbacks can dramatically accelerate the rise in temperature locally, particularly in the Arctic.

Image 21. For more details on feedbacks, see extended version of this image and discussion at

The level of methane in the atmosphere has already been rising even faster than the level of carbon dioxide, as illustrated by the image below. Moreover, there's the threat that large additional amounts of methane will suddenly be released, in particular from the Arctic seabed.


In August 2013, methane were recorded as high as 2349 ppb, as illustrated by the graph on below (added later, editor), showing that in early August, the world's mean methane level suddenly increased with at least 10 ppb compared to mean levels over the past few months.




To get an idea just how much methane has entered the atmosphere, have a look at the image below, covering several days from the start of August 2013.

[ click on image to enlarge ]


This is further illustrated by the two images below. The image directly below shows where the highest methane levels (i.e. over 1950 ppb, in yellow) were recorded on August 2, 2013.

[ click on image to enlarge ]
The image below shows the presence of methane on August 2, 2013, for a number of ranges, including at levels over 1950 ppb (this time in red).

[ click on image to enlarge ]
The methane threat is further described in the post Methane hydrates, which also features the image below.


Methane as high as 2303 ppb

This post has been updated as Methane as high as 2349 ppb.

Jumat, 28 Desember 2012

Albedo changes in the Arctic

How global warming and feedbacks are causing huge albedo changes in the Arctic.

Snow cover decline

Decline of the snow cover on land in the northern hemisphere is accelerating, as illustrated by the image below and the image underneath on the right. (1)


Image credit: Rutgers University
Fresh snow can have an albedo as high as 0.85, meaning that up to 85% of the sunlight falling on snow can get reflected back into space. As the snow melts, its structure changes making it less reflective, i.e. its albedo will go down, to as low as 40%. (2)

As a result, more sunlight gets absorbed, accelerating the melting process. Eventually, where snow melts away, spots of bare soil become exposed, and dark wet soil has a very low albedo, reflecting only between 5% and 15% of the sunlight. Thus, even more sunlight gets absorbed and the soil's temperature increases, causing more of the remaining snow to melt. (2)

Changes in vegetation can further accelerate this process. Russia's boreal forest - the largest continuous expanse of forest in the world - has seen a transformation in recent years from larch to conifer trees. Larch trees drop their needles in the fall, allowing the vast, snow-covered ground in winter to reflect sunlight and heat back into space and helping to keep temperatures in the region very cold. But conifers such as spruce and fir retain their needles, which absorb sunlight and increase the forest's ground-level heat retention. (3)

Albedo, from Wikipedia
A conversion from larch to evergreen stands in low-diversity regions of southern Siberia would generate a local positive radiative forcing of 5.1±2.6 W m−2. This radiative heating would reinforce the warming projected to occur in the area under climate change. (4)

Tundra in the Arctic used to be covered by a white blanket of snow most of the year. However, as the landscape is warming up, more trees and shrubs appear. Scientists who studied part of the Eurasian Arctic, found that willow and alder shrubs, once stunted by harsh weather, have been growing upward to the height of trees in recent decades. They now rise above the snowfall, presenting a dark, light-absorbing surface. This increased absorption of the Sun's radiation, combined with microclimates created by forested areas, adds to global warming, making an already-warming climate warm even more rapidly. (5 & 6)

Furthermore, encroachment of trees onto Arctic tundra caused by the warming may cause large release of carbon to the atmosphere, concludes a recent study. This is because tundra soil contains a lot of stored organic matter, due to slow decomposition, but the trees stimulate the decomposition of this material. (7)


Sea ice decline

In the Arctic, sea ice volume has fallen dramatically over the years, as illustrated by the image on the right. The trend points at 2014 as the year when Arctic sea ice will first reach zero volume for some time during that year. (8)

The Arctic Ocean looks set to be ice-free for a period of at least three months in 2015 (August, September and October), and for a period of at least 6 months from the year 2020 (June through to November). (9)

Decline of the Arctic sea ice is accelerating, due to numerous feedbacks. As the Arctic atmosphere warms up, any snow cover on top of the ice will melt away ever quickly, decreasing the surface albedo and thus reinforcing the warm-up. As melt ponds appear on top of the ice, the albedo will drop even further.

Sam Carana's Diagram of Doom pictures ten feedbacks that jointly work to accelerate sea ice decline. (10)

The image below shows the three areas where albedo change will be felt most in the Arctic, i.e. sea ice loss, decline of albedo in Greenland and more early and extensive retreat of snow and ice cover in other areas in the Arctic. (8)

Big changes in the Arctic within years, by Sam Carana


References

1. Northern Hemisphere Snow Cover Anomalies 1967-2012 June, Rutgers University
climate.rutgers.edu/snowcover/chart_anom.php?ui_set=1&ui_region=nhland&ui_month=6

2. Albedo, Albedo Change blog
albedochange.blogspot.com/2009/02/albedo-change.html

3. Shift in Northern Forests Could Increase Global Warming, Scientific American, March 28, 2011
scientificamerican.com/article.cfm?id=shift-northern-forests-increase-global-warming

4. Sensitivity of Siberian larch forests to climate change, Shuman et al., April 5, 2011, Wiley.com
onlinelibrary.wiley.com/doi/10.1111/j.1365-2486.2011.02417.x/abstract

5. Warming turns tundra to forest
ox.ac.uk/media/news_stories/2012/120604.html

6. Eurasian Arctic greening reveals teleconnections and the potential for structurally novel ecosystems, Macias-Fauria et al., 2012
nature.com/nclimate/journal/v2/n8/full/nclimate1558.html

7. Expansion of forests in the European Arctic could result in the release of carbon dioxide, University of Exeter news, June 18, 2012
exeter.ac.uk/news/featurednews/title_214902_en.html

8. Big changes in the Arctic within years, Sam Carana, October 26, 2012, Arctic-News blog
arctic-news.blogspot.com/2012/10/big-changes-in-arctic-within-years.html

9. Getting the Picture, Sam Carana, August 2012, Arctic-News blog
arctic-news.blogspot.com/2012/08/getting-the-picture.html

10. Diagram of Doom, Sam Carana, August 2012, Arctic-News blog
arctic-news.blogspot.com/2012/08/diagram-of-doom.html


Further reading

- Albedo change in the Arctic
arctic-news.blogspot.com/2012/07/albedo-change-in-arctic.html

- Greenland is melting at incredible rate
arctic-news.blogspot.com/2012/07/greenland-is-melting-at-incredible-rate.html

- Albedo change in the Arctic threatens to cause runaway global warming
arctic-news.blogspot.com/2012/10/albedo-change-in-the-arctic-threatens-to-cause-runaway-global-warming.html

Kamis, 01 November 2012

Forces behind Superstorm Sandy

Superstorm Sandy hit North America's east coast in a devastating way. This justifies an analysis of the forces behind Sandy and the links with global warming and climate change.

Global warming causes temperatures of oceans and the atmosphere to rise. A warming Gulf Stream fuels hurricanes traveling north along North America's east coast.

More heat translates into more wind; specifically, stronger hurricanes are getting stronger over the years, as illustrated by the inmage on the right from James Elsner et al. (2008).

Additionally, sea levels are rising, especially on the Atlantic coast of North America, which is a hotspot of accelerated sea-level rise, as described in a study by Sallenger et al. (2012).

Generally, global warming will cause more extreme weather events, says James Hansen (2012). This is especially the case for heavy rainfall events, since global warming causes more evaporation of seawater, while warm air can also carry more water. According to Kevin Trenberth (2011), the water holding capacity of air increases by about 7% per 1°C warming, which leads to increased water vapor in the atmosphere. Hence, storms, whether individual thunderstorms, extratropical rain or snow storms, or tropical cyclones, supplied with increased moisture, produce more intense precipitation events. All this leads to a greater hurricane danger; they can be expected to be stronger and wetter, causing flooding and further devastation along the east coast of North America.

The situation in the Arctic is making things even worse. Several studies, such as by Jennifer Francis (2012), by Greene et al. (2012) and by Liu et al. (2012), show that atmospheric circulation is changing as a result of sea ice loss. This circulation change results in more frequent episodes of blocking patterns that lead to increased cold surges over large parts of northern continents. Moreover, sea ice loss results in an increase in atmospheric water vapor content in the Arctic region during late autumn, and this provides enhanced moisture sources.

More open water in the Arctic Ocean results in more warming of the overlying atmosphere. This warming can be expected to change precipitation. An analysis by Julienne Stroeve (2011) shows an autumn increase in cyclone-associated precipitation over the past decade, linked to a shift in atmospheric circulation towards more frequent and more intense cyclones in the Atlantic sector of the Arctic.

The authors added that more research was needed; indeed, the devastation caused by Sandy calls for further analysis. Warming in the Arctic is accelerating at a pace several times that of the rest of the world, as a result of multiple feedbacks as described in the post Diagram of Doom; changing of the jet stream is only one out of multiple feedbacks.

Changes to the jet stream were behind Sandy's path inland. A strong and prolonged high pressure area over Greenland blocked Sandy from going north or east. This also caused it to spread out and to hang around for such a long time.

Big changes are taking place in the Arctic, in terms of sea ice loss, snow line retreat and albedo change in Greenland. Without more effective action on climate change, weather events like this can therefore be expected to hit the east coast of North America more often and with increasing force in future.


References

- The increasing intensity of the strongest tropical cyclones, James Elsner et al. (2008)
http://www.nature.com/nature/journal/v455/n7209/abs/nature07234.html

- Hotspot of accelerated sea-level rise on the Atlantic coast of North America, Asbury Sallenger et al. (2012)
http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate1597.html

- Perception of climate change, James Hansen et al. (2012)
http://www.pnas.org/content/109/37/E2415

- Changes in precipitation with climate change, Kevin Trenberth (2011)
http://www.cgd.ucar.edu/cas/Trenberth/trenberth.papers/SSD_Trenberth_2nd_proof.pdf

- Linking Weird Weather to Rapid Warming of the Arctic, Jennifer Francis (March 2012)
http://e360.yale.edu/feature/linking_weird_weather_to_rapid_warming_of_the_arctic/2501/

- An Arctic wild card in the weather, Chuck Greene and Bruce Monger (2012)
http://www.tos.org/oceanography/archive/25-2_greene.html
http://www.news.cornell.edu/stories/June12/arcticWildcard.html

- Impact of declining Arctic sea ice on winter snowfall, Jiping Liu et al. (2012)
http://www.lasg.ac.cn/UpLoadFiles/File/papers/2012/2012-pnas.jiping_liu.pdf

- Attribution of recent changes in autumn cyclone associated precipitation in the Arctic, Julienne Stroeve et al. (2011)
http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0870.2011.00515.x/abstract
http://www.tellusa.net/index.php/tellusa/article/view/15846/17736
poster at:
http://soa.arcus.org/sites/soa.arcus.org/files/sessions/2-3-arctic-change-and-natural-variability/pdf/stroeve.pdf

Related

- Warming Gulf Stream causes methane release
http://arctic-news.blogspot.com/2012/10/warming-gulfstream-causes-methane-release.html

- Diagram of Doom
http://arctic-news.blogspot.com/2012/08/diagram-of-doom.html

- Opening further Doorways to Doom
http://arctic-news.blogspot.com/2012/08/opening-further-doorways-to-doom.html

- Climate Change Sandy Says to US: 'Take That, Idiots!'
http://arctic-news.blogspot.com/2012/10/climate-change-sandy-says-to-us-take-that-idiots.html

- Hurricane Sandy moving inland
http://arctic-news.blogspot.com/2012/10/hurricane-sandy-moving-inland.html

- Big changes in Arctic within years
http://arctic-news.blogspot.com/2012/10/big-changes-in-arctic-within-years.html