ONE TOWN SQUARE: at the intersection of peak oil, climate change, and land use

Developed countries are “outsourcing” more than a third of their carbon emissions associated with products and services to other countries, according to a new study by scientists at the Carnegie Institution for Science. To be meaningful, regional climate policy thus needs to take into account emissions embodied in trade, not just domestic emissions.

This map shows the flow of carbon emissions embodied in trade among the major exporting and importing countries. Net exporting countries are in blue and net importers in red. China is by far the largest exporter of carbon dioxide emissions. Arrows indicate direction and magnitude of flow; numbers are megatonnes. (Steven Davis/Carnegie Institution for Science)

The study finds that, per person, about 2.5 tons of carbon dioxide are consumed in the U.S. but produced somewhere else. The United States is both a major importer and a major exporter of emissions embodied in trade. The net result is that the U.S. outsources about 11% of total consumption-based emissions, primarily to the developing world.

Says co-author Ken Caldeira, a researcher in the Carnegie Institution’s Department of Global Ecology:

Instead of looking at carbon dioxide emissions only in terms of what is released inside our borders, we also looked at the amount of carbon dioxide released during the production of the things that we consume.

Caldeira and lead author Steven Davis, also at Carnegie, used published trade data from 2004 to create a global model of the flow of products across 57 industry sectors and 113 countries or regions. By allocating carbon emissions to particular products and sources, the researchers were able to calculate the net emissions “imported” or “exported” by specific countries.

For Europeans, the figure can exceed four tons per person. In Switzerland and several other small countries, outsourced emissions exceeded the amount of carbon dioxide emitted within national borders. Most of these emissions are outsourced to developing countries, especially China.

Davis explains:

Just like the electricity that you use in your home probably causes CO2 emissions at a coal-burning power plant somewhere else, we found that the products imported by the developed countries of western Europe, Japan, and the United States cause substantial emissions in other countries, especially China. On the flip side, nearly a quarter of the emissions produced in China are ultimately exported.

Where CO2 emissions occur doesn’t matter to the climate system. Effective policy must have global scope. To the extent that constraints on developing countries’ emissions are the major impediment to effective international climate policy, allocating responsibility for some portion of these emissions to final consumers elsewhere may represent an opportunity for compromise.

The report is published online in the March 8, 2010 Proceedings of the National Academy of Sciences.

Methane is leaking from the East Siberian Arctic Shelf into the atmosphere at an alarming rate, says a press release from the National Science Foundation.

Climate scientists have long worried that global warming could unlock the vast quantities of the greenhouse gas methane that are frozen in the Arctic permafrost, kicking off a feedback loop that could end in catastrophe. Now, an international research team led by University of Alaska Fairbanks scientists Natalia Shakhova and Igor Semiletov has found signs that it may already be happening.

The East Siberian Arctic Shelf is shallow, 50 meters (164 feet) or less in depth, which means it has been alternately submerged or terrestrial, depending on sea levels throughout Earth’s history. During the Earth’s coldest periods, it is a frozen arctic coastal plain, and does not release methane. As the Earth warms and sea level rises, it is inundated with seawater, which is 12-15 degrees warmer than the average air temperature.

The press release quotes Shakhova:

It was thought that seawater kept the East Siberian Arctic Shelf permafrost frozen. Nobody considered this huge area.

Top left: Bubble plumes (probably dominated by CH4) rising from the seafloor registered by geophysical instrumentation. Top right: Seismic image showing gas charged sediments and gas release from the bottom. Bottom left: Positions of oceanographic stations with bathymetry lines. Bottom right: Fluxes of CH4 venting to the atmosphere over the ESAS. Source: Shakhova et al.

The study, “Extensive Methane Venting to the Atmosphere from Sediments of the East Siberian Arctic Shelf”, is published in the March 5 edition of the journal Science. It shows that the permafrost under the East Siberian Arctic Shelf, long thought to be an impermeable barrier sealing in methane, is perforated and is starting to leak large amounts of methane into the atmosphere. Release of even a fraction of the methane stored in the shelf could trigger abrupt climate warming.

A quote from the study in article at Green Car Congress captures the scientific community’s reluctance to sound alarmist:

Although the oceanic CH₄ flux should be revised, the current estimate is not alarmingly altering the contemporary global CH₄ budget. These findings do change our view of the vulnerability of the large sub-sea permafrost carbon reservoir on the ESAS; the permafrost “lid” is clearly perforated, and sedimentary CH₄ is escaping to the atmosphere.

To discern whether this extensive CH₄ venting over the ESAS is a steadily ongoing phenomenon or signals the start of a more massive CH₄ release period, there is an urgent need for expanded multifaceted investigations into these inaccessible but climate-sensitive shelf seas north of Siberia.

In this New York Times article, Dr. Shakhova reiterates the notes of scientific caution:

I would not go so far as to suggest any implications. We are at the very beginning of research.

The permafrost contains 1.5 trillion tons of frozen carbon – about twice as much carbon as contained in the atmosphere – much of which would be released as methane.  As a greenhouse gas, Methane is 25 times more potent than CO2 over a 100 year time horizon but 72 times as potent over 20 years. Atmospheric concentrations of methane have more than doubled since pre-industrial times.

An article in Pysorg.com reports that a huge iceberg has broken off of Antarctica:

An iceberg the size of Luxembourg knocked loose from the Antarctic continent earlier this month could disrupt the ocean currents driving weather patterns around the globe, researchers said Thursday.

Another iceberg known as B9B, which had been jammed against the Antarctic continent for more than 20 years, began to drift and smashed into the Metz tongue.

I found this satellite picture of the event at the European Space Agency website:

The 2550 square-kilometer (985 square-mile) block broke off on February 12 or 13 from the Mertz Glacier Tongue, a 160-kilometer spit of floating ice protruding into the Southern Ocean from East Antarctica due south of Melbourne. B9B is a remnant of a 2,000-square-mile iceberg that calved in 1987, making it one of the largest icebergs ever recorded in Antarctica.

The resulting new iceberg, along with B9B, have since drifted into an adjoining area called a ploynya – an area that produce dense water, super cold and rich in salt, that sinks to the bottom of the sea and drives the conveyor-belt like circulation around the globe. The Metz Glacier Polynya is particularly strong and accounts for 20 percent of the “bottom water” in the world.

Benoit Legresy, a French glaciologist who works at the Laboratory for Geophysics and Oceanographic Space Research in Toulouse and who has been monitoring the Metz glacier, explains how the icebergs could possibly disrupt ocean circulation patterns:

[I]f they stay in this area – which is likely – they could block the production of this dense water, essentially putting a lid on the polynya.

New research shows that modern farming – the kind practiced on nearly all farmland in the United States and touted around the world as the “green revolution” – destroys soil carbon. Synthetic nitrogen contributes to climate change and undermines long-term soil productivity because synthetic nitrogen breaks down organic matter faster than plant residue creates it.

In papers published in 2007 and 2009 University of Illinois researchers Richard Mulvaney, Saeed Khan, and Tim Ellsworth argue that the net effect of synthetic nitrogen use is to reduce soil’s organic matter content. They hypothesize that nitrogen fertilizer stimulates soil microbes, which then feast on organic matter. Over time, the impact of this enhanced microbial appetite outweighs the benefits of the additional crop residue left behind as a result of increased fertilization.

Tom Philpot summarizes their findings in a post at Grist:

And their analysis gets more alarming. Synthetic nitrogen use, they argue, creates a kind of treadmill effect. As organic matter dissipates, soil’s ability to store organic nitrogen declines. A large amount of nitrogen then leeches away, fouling ground water in the form of nitrates, and entering the atmosphere as nitrous oxide (N2O), a greenhouse gas with some 300 times the heat-trapping power of carbon dioxide. In turn, with its ability to store organic nitrogen compromised, only one thing can help heavily fertilized farmland keep cranking out monster yields: more additions of synthetic N.

The loss of organic matter has other ill effects, the researchers say. Injured soil becomes prone to compaction, which makes it vulnerable to runoff and erosion and limits the growth of stabilizing plant roots. Worse yet, soil has a harder time holding water, making it ever more reliant on irrigation. As water becomes scarcer, this consequence of widespread synthetic N use will become more and more challenging.

In short, “the soil is bleeding,” Mulvaney told me in an interview.

The idea that synthetic fertilizers destroy soil health is not new. Philpot quotes from the book The Soil and Health by British agronomist Sir Albert Howard, a touchstone of organic farming first published in 1947:

The use of artificial manure, particularly [synthetic nitrogen] … does untold harm. The presence of additional combined nitrogen in an easily assimilable form stimulates the growth of fungi and other organisms which, in the search for organic matter needed for energy and for building up microbial tissue, use up first the reserve of soil hummus and then the more resistant organic matter which cements soil particles.

A recent report by UNEP and the UN Conference on Trade and Development is consistent with the researchers’ results, finding that in Africa yields had more than doubled where organic, or near-organic practices had been used, with yields jumping 128% in east Africa. The study found that organic practices outperformed traditional methods and chemical-intensive conventional farming and produced environmental benefits such as improved soil fertility, better retention of water and resistance to drought.

Research by the U.S. Geological Survey documents that every ice front in the southern part of the Antarctic Peninsula has been retreating overall from 1947 to 2009, with the most dramatic changes occurring since 1990.

The report, “Coastal-Change and Glaciological Map of the Palmer Land Area, Antarctica: 1947—2009” and its accompanying map is available online.

The press release explains why the loss of ice shelves is so significant:

The ice shelves are attached to the continent and already floating, holding in place the Antarctic ice sheet that covers about 98 percent of the Antarctic continent. As the ice shelves break off, it is easier for outlet glaciers and ice streams from the ice sheet to flow into the sea. The transition of that ice from land to the ocean is what raises sea level.

The press release also quotes USGS scientist Jane Ferrigno:

The loss of ice shelves is evidence of the effects of global warming. We need to be alert and continually understand and observe how our climate system is changing.

The Antarctic Peninsula’s southern section contains five major ice shelves: Wilkins, George VI, Bach, Stange and the southern portion of Larsen Ice Shelf. The ice lost since 1998 from the Wilkins Ice Shelf alone totals more than 4,000 square kilometers, an area larger than the state of Rhode Island.

Ice-front retreat of the Wilkins Ice Shelf from 1947 to 2009

Last year Post Carbon Oregon had a series of posts documenting the disintegration of the ice bridge connecting the Wilkins ice shelf to Charcot Island, featuring photos from the European Space Agency’s Webcam in Space. Pretty spectacular stuff.

At the Royal Society in London, scientists at a conference  on greenhouse gases  report that levels of methane in the atmosphere, after a decade of near-zero growth, began rising in 2007 when an unprecedented heat wave in the Arctic caused a record shrinking of the sea ice and have continued to rise significantly through 2008 and 2009.

An article in the U.K. Independent includes a quotation from the presentation, titled Global atmospheric methane in 2010: budget, changes and dangers:

[G]lobally averaged atmospheric methane increased by [approximately] 7ppb (parts per billion) per year during 2007 and 2008. . . . During the first half of 2009, globally averaged atmospheric CH4 was [approximately] 7ppb greater than it was in 2008, suggesting that the increase will continue in 2009. There is the potential for increased CH4 emissions from strong positive climate feedbacks in the Arctic where there are unstable stores of carbon in permafrost . . . so the causes of these recent increases must be understood.

Global atmospheric levels of the gas now stand at about 1,790 parts per billion. They began to be measured in 1984, when they stood at about 1,630ppb.

The Independent also quotes Euan Nisbet, one of the study’s authors:

“It may just be a couple of years of high growth, and it may drop back to what it was. But there is a concern that things are beginning to change towards renewed growth from feedbacks.

Over a relatively short period, such as 20 years, methane (CH4) has a global warming potential more than 60 times as powerful as CO2, although it decays more quickly.

Many climate scientists fear that frozen Arctic tundra, like this at Sermermiut in Greenland, could be a ticking time bomb. Over thousands of years the methane has accumulated under the ground at northern latitudes all around the world. But as temperatures rise and the permafrost begins to melt, that methane could be released – with potentially catastrophic results.

A recent post reported on scientists’ findings that Greenland’s glaciers are melting from the bottom up. Findings from another team of scientists help explain why: subtropical waters from warmer latitudes are reaching Greenland’s glaciers, driving melting and likely triggering an acceleration of ice loss.

Credit: Jack Cook, Woods Hole Oceanographic Institution

The research team, led by Fiamma Straneo, a physical oceanographer at Woods Hole Oceanographic Institution, found that subtropical waters are reaching Greenland’s glaciers, driving melting and likely triggering an acceleration of ice loss. Melting ice also means more fresh water in the ocean, which could flood into the North Atlantic and disrupt a global system of currents, known as the Ocean Conveyor.

Science Daily quotes Straneo:

This is the first time we’ve seen waters this warm in any of the fjords in Greenland. The subtropical waters are flowing through the fjord very quickly, so they can transport heat and drive melting at the end of the glacier.

The Greenland ice sheet’s contribution to sea level rise over the last decade has doubled due to increased melting and especially to the widespread acceleration of outlet glaciers.

The research teamconducted two extensive surveys during July and September of 2008 in Sermilik Fjord, a 100-kilometer long glacial fjord in East Greenland connecting Helheim Glacier with the Irminger Sea. In 2003 alone, Helheim Glacier retreated several kilometers and almost doubled its flow speed.  Deep inside the fjord, researchers found subtropical water as warm as 39 degrees Fahrenheit (4 degrees Celsius). The team also reconstructed seasonal temperatures on the shelf using data collected by 19 hooded seals tagged with satellite-linked temperature depth-recorders. The data revealed that the shelf waters warm from July to December, and that subtropical waters are present on the shelf year round.

A study published in Nature Geoscience finds that submarine melting is causing Greenland’s glaciers to melt from underneath and calve off.  As the glaciers thin and become unpinned from their moorings on the sea bed, they then flow more rapidly into the sea.

Rates of submarine melting are two orders of magnitude (100 times) larger than surface melt rates. The rate of submarine melting is comparable to rates of iceberg discharge.

Here’s the abstract:

Widespread glacier acceleration has been observed in Greenland in the past few years1, associated with the thinning of the lower reaches of the glaciers as they terminate in the ocean. These glaciers thin both at the surface, from warm air temperatures, and along their submerged faces in contact with warm ocean waters8. Little is known about the rates of submarine melting and how they may affect glacier dynamics. Here we present measurements of ocean currents, temperature and salinity near the calving fronts of the Eqip Sermia, Kangilerngata Sermia, Sermeq Kujatdleq and Sermeq Avangnardleq glaciers in central West Greenland, as well as ice-front bathymetry and geographical positions. We calculate water-mass and heat budgets that reveal summer submarine melt rates ranging from 0.7±0.2 to 3.9±0.8?m?d?1. These rates of submarine melting are two orders of magnitude larger than surface melt rates, but comparable to rates of iceberg discharge. We conclude that ocean waters melt a considerable, but highly variable, fraction of the calving fronts of glaciers before they disintegrate into icebergs, and suggest that submarine melting must have a profound influence on grounding-line stability and ice-flow dynamics.

The National Snow and Ice Data Center (NSIDC) reports that Arctic sea ice extent continues to track way below normal, despite cool temperatures over most of the Arctic Ocean in January.

Reuters quotes NSIDC director Mark Serreze:

It’s not that the ice keeps melting, it’s just not growing very fast.
We’ve grown back ice in the winter, but that ice tends to be thin and that’s the problem. You set yourself up for a world of hurt in summer. The ice that is there is also thinner than it was before and thinner ice simply takes less energy to melt out the next summer.

With thinner, more fragile ice and less cover,

You’ve got a double whammy going on.

If Arctic ice fails to build up sufficiently during the dark, cold winter months, it is likely to melt faster and earlier when spring comes.

A Canadian research project has found that climate change is happening much faster than the most pessimistic models expected.  Models predicted only a few years ago that the Arctic would be ice-free in summer by the year 2100, but the increasing pace of climate change now suggests it could happen between 2013 and 2030. Losing sea ice has impacts on everything else that goes on in the Earth’s systems.

A new study by the Pew Environment Group estimates the financial cost  to the world economy  of a warming and melting Arctic will be at least $2.4 trillion over the next 40 years. The study looks at the “social cost of carbon,” including the cost of climate change on agriculture, energy production, water availability, sea level rise, and flooding.

By the end of January, ice extent had dropped below the extent observed in January 2007. This winter continues the recent trend of slower Arctic ice growth.

The summer Arctic sea ice melt season now lasts nearly a month longer than it did in the 1980s. A later start of freeze-up and an earlier start to the melt season both contribute to the change. A recent paper by Thorsten Markus at NASA Goddard Space Flight Center suggests that the later freeze-up is the dominant factor lengthening the melt season. The analysis shows that, on average, autumn freeze-up starts nearly four days later each decade. Extensive open water at the end of the summer melt season, combined with warmer autumns, delay the autumn freeze-up. The larger expanses of open water absorb more solar energy, and before ice can form again, that heat must be released back to the atmosphere. This trend is most pronounced in the Beaufort, Chukchi and Laptev seas.

New NASA-led research shows that the melt season for Arctic sea ice has lengthened by an average of 20 days over the span of 28 years, or 6.4 days per decade.

The research team discovered that the melt season lengthened the most – more than 10 days per decade – in Hudson Bay, the East Greenland Sea, the Laptev and East Siberian Seas, and the Chukchi and Beaufort Seas.

Earlier melt means more heat can be absorbed by the open water, promoting more melting and later freeze-up dates — more than eight days per decade later in some areas.

Thorsten Markus of NASA’s Goddard Space Flight Center in Greenbelt, Md. explains how the feedback loop works:

This feedback process has always been present, yet with more extensive open water this feedback becomes even stronger and further boosts ice loss. Melt is starting earlier, but the trend towards a later freeze-up is even stronger because of this feedback effect.

Scientists have upped their estimates of the waves that a “100 year event” might produce along the coast of the Pacific Northwest. Their finding heighten concerns for flooding, coastal erosion and structural damage.

Waves crawl up against the lower level of a structure in Neskowin, Oregon, during a storm in January, 2008. (Photo by Armand Thibault, Neskowin)

As recently as 1996, the maximum in ocean wave heights was estimated to be 33 feet. In a study just published online in the journal Coastal Engineering, scientists from Oregon State University and the Oregon Department of Geology and Mineral Industries conclude that the highest waves may be as much as 46 feet and the 100-year wave height could actually exceed 55 feet. Impacts of the bigger waves would dwarf impacts expected from sea level rise in coming decades.

Over the last few decades, increasing wave heights have had 2 – 3 times the impact of sea level rise in terms of erosion, flooding and damage. The largest wave height increases have occurred off the Washington and northern Oregon coasts, with less increase in southern Oregon and nothing of significance south of central California.

Possible causes cited are changes in storm tracks, higher winds, more intense winter storms, or other factors probably related to global warming but also possibly related to periodic climate fluctuations such as the Pacific Decadal Oscillation. What is clear is that waves are getting bigger.

The significant rise in sea level expected over future decades and centuries will only add to the damage already being done by higher waves.

A new NASA analysis of global surface temperature shows the decade January 2000 to December 2009 was the warmest decade on record.

Temperature changes for the last decade—January 2000 to December 2009—relative to the 1951-1980 mean. Warmer areas are in red, cooler areas in blue. The largest temperature increases occurred in the Arctic and a portion of Antarctica. Credit: NASA

2009 was tied for the second warmest year in the modern record, a fraction of a degree behind 2005. In the Southern Hemisphere, 2009 was the warmest year since modern records began in 1880.

Average global temperatures have increased by about 0.8°C (1.4°F) since 1880. Rising levels of carbon dioxide and other greenhouse gases are the key factors causing the rise in temperatures since 1880.

Other factors, including changes in the sun’s irradiance, oscillations of sea surface temperature in the tropics, and changes in aerosol levels, can also cause slight increases or decreases in the planet’s temperature. Aerosols produced by burning fossil fuels have probably counteracted about half of the warming produced by man-made greenhouse gases. In 2009, even the deepest solar minimum in the period of satellite data wasn’t enough to offset global warming.

Scientists have found evidence confirming predictions of climate models that higher atmospheric CO2 levels will lead to acidification of Earth’s oceans.

Scientists from the University of South Florida College of Marine Science measured CO2 levels in the northeastern Pacific Ocean. By comparing pH readings from 1991 and from 2006, they found the first direct evidence of acidification across an entire ocean basin, leaving no doubt that growing CO2 levels in the atmosphere are exerting major impacts on the world’s oceans.

If greenhouse gas emissions continue unabated, by the end of the century surface water pH would drop approximately 0.4 pH units and the carbonate ion concentration would decrease almost 50%. This surface ocean pH would be lower than it has been for more than 20 million years. Even if substantial reductions in emissions are made, ocean acidification will continue for hundreds of years to come, which means we are already committed to many centuries of ugly consequences.

The study is published in the American Geophysical Union’s journal Geophysical Research Letters.

Scientists have recorded a massive spike in the amount of methane seeping from Arctic permafrost. Methane emissions from the Arctic increased by 31% from 2003-07. The increase represents about 1m extra tonnes of methane each year.

Sharply rising temperatures are to blame. Global warming is occurring twice as fast in the Arctic than anywhere else on Earth. Some regions have already warmed by 2.5C, and temperatures there are projected to increase by more than 10C by 2100 if carbon emissions continue to rise at current rates.

The new study supports scientists who warn that even modest levels of global warming could trigger huge increases in methane release from permafrost. Estimates of the amount of carbon trapped in shelf permafrost are in the range of 1,600 billion tonnes – roughly twice as much carbon as in the atmosphere now. Billions of tonnes of that sequestered carbon could be released by just a 2C average global rise, a positive feedback that could push Earth’s climate past a tipping point leading to catastrophic climate change.

The Guardian quotes Paul Palmer, a scientist at Edinburgh University who worked on the new study:

High latitude wetlands are currently only a small source of methane but for these emissions to increase by a third in just five years is very significant. It shows that even a relatively small amount of warming can cause a large increase in the amount of methane emissions.

Just over half of all methane emissions came from the tropics, with some 20m tonnes released from the Amazon River basin each year, and 26m tonnes from the Congo basin. Rice paddy fields across China and south and southeast Asia produced almost one-third of global methane, some 33m tonnes. Only 2% of global methane comes from Arctic latitudes, the study found, though the region showed the largest increases. The 31% rise in methane emissions there from 2003-07 was enough to help lift the global average increase to 7%.

The study is published in the journal Science.

At the meeting of the American Geophysical Union in San Francisco this week, scientists report that new data confirm that another positive feedback mechanism is at work. New temperature and water vapor observations have corroborated climate model predictions that the warming of our climate produced by carbon dioxide will be greatly exacerbated – more than doubled – by water vapor. As the climate warms, the atmosphere becomes more humid. Since water is a greenhouse gas, it serves as a powerful positive feedback to the climate system, amplifying the initial warming.

Here’s the abstract to the Science study:

Wetlands are the largest individual source of methane (CH4), but the magnitude and distribution of this source are poorly understood on continental scales. We isolated the wetland and rice paddy contributions to spaceborne CH4 measurements over 2003–2005 using satellite observations of gravity anomalies, a proxy for water-table depth {Gamma}, and surface temperature analyses TS. We find that tropical and higher-latitude CH4 variations are largely described by {Gamma} and TS variations, respectively. Our work suggests that tropical wetlands contribute 52 to 58% of global emissions, with the remainder coming from the extra-tropics, 2% of which is from Arctic latitudes. We estimate a 7% rise in wetland CH4 emissions over 2003–2007, due to warming of mid-latitude and Arctic wetland regions, which we find is consistent with recent changes in atmospheric CH4.

Scientists have uncovered a dramatic increase in methane gas seeping from the Arctic seabed.

A team of scientists led by Igor Semiletov from the University of Alaska at Fairbanks measured carbon fluxes around the north of Russia. Semiletov tells what they found:

Methane release from the East Siberian Shelf is underway and it looks stronger than it was supposed [to be].

Methane seepage recorded last summer was the highest ever measured in the Arctic Ocean.

Higher concentrations of atmospheric methane are contributing to global temperature rise; this in turn is projected to cause further permafrost melting and the release of yet more methane in a feedback loop. A worst-case scenario is one where the feedback passes a tipping point and billions of tonnes of methane are released suddenly, resulting in rapid increases in global temperatures and mass extinction of species.

Siberia’s shallow shelf areas act as a giant frozen depository of carbon in the form of CO2 and methane (often stored as compacted solid gas hydrates). This undersea permafrost was until recently considered to be stable, and much of the gas that did escape was absorbed by the sea. But Semiletov’s team found, due to the shallow depth of arctic shelves, methane is reaching the atmosphere without reacting to become CO2 or dissolving in the ocean.

Methane measured in the atmosphere around the region is 100 times higher than normal background levels, and in some cases 1,000 times higher.

Estimates of the amount of carbon trapped in shelf permafrost are in the range of 1,600 billion tonnes – roughly twice as much carbon as in the atmosphere now. The release of this carbon from destabilized ocean sediments and permafrost would have catastrophic effect on our climate and life on Earth.

The rapid loss of summer ice cover over the Arctic Ocean is creating internal waves in the Arctic waters that could dramatically accelerate the sea ice loss.

That’s what Luc Rainville of the University of Washington’s Applied Physics Laboratory in Seattle and his colleague Rebecca Woodgate report in a study just published in the latest issue of Geophysical Research Letters.

Underwater waves in the Pacific and Atlantic, stirred up by surface winds, keep the oceans from becoming stratified in layers. Near Hawaii, for example, such underwater waves have been measured at depths of up to 200 meters, preventing the ocean from becoming a quiet pool with warm waters on top and colder waters below. The ice-topped Arctic Ocean, on the other hand, is just such a stratified, calm place because sea ice muffles all waves “like a big damper,” as Rainville explains. But that is becoming less the case as summer sea ice melt is opening up ever wider expanses of water.

Unlike any other ocean basin, the Arctic has a lot of very fresh, very cold water on top from melted ice – the cold halocline layer. But below about 100 meters the waters become very salty and slightly warmer. If internal waves become powerful enough to mix these waters, then the warmer surface could accelerate the melting of sea ice.

Here’s the abstract:

The Arctic is generally considered a low energy ocean. Using mooring data from the northern Chukchi Sea, we confirm that this is mainly because of sea ice impeding input of wind energy into the ocean. When sea ice is present, even strong storms do not induce significant oceanic response. However, during ice free seasons, local storms drive strong inertial currents (>20 cm/s) that propagate throughout the water column and significantly deepen the surface mixed layer. The large vertical shear associated with summer inertial motions suggests a dominant role for localized and seasonal vertical mixing in Arctic Ocean dynamics. Our results imply that recent extensive summer sea ice retreat will lead to significantly increased internal wave generation especially over the shelves and also possibly over deep waters. This internal wave activity will likely dramatically increase upper layer mixing in large areas of the previously quiescent Arctic, with important ramifications for ecosystems and ocean dynamics.

The National Snow and Ice Data Center reports temperatures over the Arctic this winter have so far been unusually warm. Paradoxically, this could affect the winds that push the ice out of the Arctic to warmer waters, helping to retain some of the second- and third-year ice through the winter and potentially rebuild some of the older, multiyear ice that has been lost over the past few years. However, NSIDC cautions it is not known whether these weather conditions will persist through the winter or what the net effect will be.

As the chart below shows, Arctic sea ice extent has been declining steadily over the past 30 years.

Arctic sea ice is now tracking at or near record lows.

On Friday, the U.S. and China conspired to blow up the Copenhagen climate talks while calling the “accord” they did sign “meaningful and unprecedented” even though it commits to no action whatsoever.

Then on Sunday, U.S. and Chinese scientists released a new study concluding calculations for man-made global warming may be underestimated by between 30 and 50 percent.

The study, Palaeoclimate: Global warmth with little extra CO2, is published in the January 2010 journal Nature Geoscience. The study looked at the period three to five million years ago—the most recent episode of sustained global warming with geography similar to today’s. Using sediment drilled from the ocean floor, the scientists’ reconstruction of carbon dioxide concentrations found that the global temperature was between two and three degrees C (3.6 and 5.4 degrees F) higher than today even though carbon dioxide levels were similar to the current ones.

Here’s the abstract:

In the Early Pliocene, three to five million years ago, global temperatures were about 3–4|[deg]| C warmer than today in the low latitudes, and up to 10|[deg]| C warmer nearer the poles. Climate simulations and reconstructions of this relatively recent period (geologically speaking) may help constrain realistic magnitudes of future warming.

The paper’s lead author, Yale’s Mark Pagani, sums up what the study’s findings mean:

This work and other ancient climate reconstructions reveal that Earth’s climate is more sensitive to atmospheric carbon dioxide than is discussed in political circles.

Oops – looks like a 3 – 4 degree rise in temperatures is already baked into the cake, even if greenhouse gas emissions were to be completely and immediately halted.

But Obama looked good getting an agreement, any agreement – didn’t he?

Not being Bush is not good enough.

A new report warns that by 2100 the sea level will rise by up to 1.4 meters — far exceeding the 0.59 meter rise predicted only two years ago by the IPCC in its 2007 4th Assessment Report.

SCAR scientists said that the IPCC underestimated grossly how much the melting of the Antarctic and Greenland ice sheets would contribute to total sea-level rises.

The report found that the hole in the ozone layer caused by the release of CFC (chlorofluorocarbon) gases has cooled temperatures and shielded most of Antarctica from global warming. Measures to control CFC gases will begin to “heal” the hole in around 50 to 60 years, leading to additional warming of about 3.0 Celsius (5.4 Fahrenheit) by century’s end. Even with the ozone hole, Antarctic ice sheets are already starting to melt.

The study also report the powerful Antarctic Circumpolar Current – which, by keeping warm ocean waters away from Antarctica enables that continent to maintain its huge ice sheet – has been warming faster than the global ocean as a whole. This is disrupting the region’s ecosystems, including enabling invasive species to compete with and replace native Antarctic inhabitants. That process has already begun on the Antarctic Peninsula. Sea ice loss and ocean acidification are directly affecting wildlife, and could reduce Antarctica’s rich biodiversity. Tiny krill at the bottom of the food chain have declined significantly, and in some areas Adelie penguin populations have dropped due to reduced sea ice and prey.

The report, Antarctic Climate Change and the Environment (warning – 20 MB) was prepared by the more than 100 scientists composing the Scientific Committee on Antarctic Research. The press release is available, as is a summary of the study’s top ten points.

“The Copenhagen Diagnosis: Climate Science Report” has been released as a lead-up to the global climate talks to be held in Copenhagen next month.

The intent of the 26 scientists who participated in drafting the report was to bring the IPCC 2007 Working Group 1 report up to date with the latest science. The report and a summary are available for download here.

The report warns that global emissions need to peak between 2015 and 2020 and then decline rapidly if catastrophic climate change is to be avoided.

Here are some of the points made in the report:

• Global carbon dioxide emissions from fossil fuels in 2008 were nearly 40% higher than those in 1990.
• Over the past 25 years temperatures have increased at a rate of 0.190C per decade, in very good agreement with predictions based on greenhouse gas increases.
• Both the Greenland and Antarctic ice-sheets are losing mass at an increasing rate. Melting of glaciers and ice-caps in other parts of the world has also accelerated since 1990.
• Summer-time melting of Arctic sea-ice has accelerated far beyond the expectations of climate models.
• Sea-level rise (3.4 mm/yr over the past 15 years) is 80% above past IPCC predictions, consistent with a doubling in contribution from melting of glaciers, ice caps and the Greenland and West-Antarctic ice-sheets.
• By 2100, global sea-level is likely to rise at least twice as much as projected. Sea-level will continue to rise for centuries even if global temperatures are stabilized. Sea levels will inevitably rise by several meters over the next few centuries.
• Vulnerable elements in Earth’s climate system could be pushed past irreversible “tipping points” if warming continues unabated.