The U.N. World Meteorological Organization reports greenhouse gas concentrations in the atmosphere reached a new high in 2010 – and the rate of increase has accelerated.

The publication WMO Greenhouse Gas Bulletin: The State of Greenhouse Gases in the Atmosphere Based on Global Observations through 2010 reports there was a 29% increase in radiative forcing from greenhouse gases between 1990 and 2010.

Globally averaged levels of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) have reached new highs, with CO2 at 389.0 ppm, CH4 at 1808 ppb, and N2O at 323.2 ppb. These values are greater than those in pre-industrial times (before 1750) by 39%, 158% and 20%, respectively.

CO2 is the single most important man-made greenhouse gas in the atmosphere, contributing about 64% of the total increase in climate forcing by greenhouse gases. CO2 emissions result from the burning of fossil fuels, deforestation, and changes in land-use.

CH4 – contributes about 18% to the overall global increase in radiative forcing. Methane emissions result from human activities such as cattle raising, rice planting, fossil fuel exploitation and landfills. About 40% of methane emissions come from natural sources such as wetlands. After a period of temporary relative stabilization from 1999 to 2006, atmospheric methane has again been rising, likely because of the thawing of the methane-rich northern permafrost and increased emissions from tropical wetlands.

N2O contributes about 6% to the overall global increase in radiative forcing. N2O emissions result from the use of nitrogen-containing fertilizers, including manure, which has profoundly affected the global nitrogen cycle. Over a 100 year period, its impact on climate is 298 times greater than equal emissions of carbon dioxide.

Halocarbons together account for about 12% of the increase in radiative forcing. Some halocarbons such as chlorofluorocarbons (CFCs), previously used as refrigerants, as propellants in spray cans and as solvents, are decreasing slowly as a result of international action to preserve the Earth’s protective ozone layer. However, concentrations of other gases such as HCFCs and HFCs, which have been substituted for CFCs because they are less damaging to the ozone layer, are increasing rapidly. HCFCs and HFCs are very potent greenhouse gases and last much longer in the atmosphere than carbon dioxide.

While greenhouse gases continue to rise at an increasing rate, the leaders of Earth’s “greatest” nations continue to fiddle. After the Copenhagen climate talks in 2009 ended in a debacle, governments pledged to try to sign a new treaty in 2012, when the current provisions of the Kyoto protocol expire. Fiona Harvey at the U.K. Guardian reports that before critical climate talks even begin next week, most of the world’s leading economies are privately admitting that no new global climate agreement will be reached before 2016 at the earliest – and that even if it were negotiated by then, they would stipulate it could not come into force until 2020.

2020 is too late if catastrophic climate change is to be averted. Fatih Birol, chief economist at the International Energy Agency (IEA) and one of the world’s foremost authorities on climate economics, warns:

If we do not have an international agreement whose effect is put in place by 2017, then the door to holding temperatures below 2 ° C will be closed forever.

While global leaders fiddle, Earth is already beginning to burn (and drown). In an advance draft of the Summary for Policymakers of the upcoming report Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (SREX, the IPCC observes there has been an increase in temperature extremes, extreme precipitation events, and economic losses from extreme weather- and climate-related disasters.

While noting the effects of climate change are already being felt, the IPCC is pulling its punches. Joseph Romm at Climate Progress fumes:

The thing to remember about IPCC reports is that pretty much everyone involved has to sign off on every word, so it is inevitably a least common denominator document. The actual scientific literature from 2011 is far more useful than this report.

Romm in his post discusses and provides links to many recent studies showing the systemic influence of global warming on climate events. Climate change is already here – and will keep getting worse.

If we don’t change direction soon, we’ll end up where we’re heading.

So begins the Executive Summary of the International Energy Agency’s World Energy Outlook 2011.

And where is it we are heading?

We cannot afford to delay further action to tackle climate change if the long-term target of limiting the global average temperature increase to 2°C, as analysed in the 450 Scenario, is to be achieved at reasonable cost. In the New Policies Scenario, the world is on a trajectory that results in a level of emissions consistent with a long-term average temperature increase of more than 3.5°C. Without these new policies, we are on an even more dangerous track, for a temperature increase of 6°C or more.

Four-fifths of the total energy-related CO2 emissions permissible by 2035 in the 450 Scenario are already “locked-in” by our existing capital stock (power plants, buildings, factories, etc.). If stringent new action is not forthcoming by 2017, the energy-related infrastructure then in place will generate all the CO2 emissions allowed in the 450 Scenario up to 2035, leaving no room for additional power plants, factories and other infrastructure unless they are zero-carbon, which would be extremely costly.

Unfortunately, we’ve come to learn 450 ppm CO2 is much too high to avoid catastrophic climate consequences.

The conclusion that limiting CO2-equivalent to 450 ppm will succeed in limiting temperature increase to 2°C is based on the assumption that no feedback loops will kick in, an assumption that is already proving unfounded – for example, Arctic amplification is already kicking in and thawing permafrost will further accelerate global warming.

If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO₂ will need to be reduced from its current ~390 ppm to at most 350 ppm. To be safe, we’ll likely have to get back to pre-industrial levels of 280 ppm, and rather quickly.

And how are we doing? The European Environment Agency keeps track.

Even under the most optimistic (more accurately, unrealistic) scenarios, it’s looking like the IEA’s outlook is unjustifiably rosy. The concentration of CO2 in the atmosphere is now about 390 ppm, however, the concentration of CO2e has already hit 450 ppm.

A 2011 paper by Dr. Minqi Li of the University of Utah lays out the horrible and inexorable consequences of continuing to pump greenhouse gases into the atmosphere:

It is now widely understood that human economic activities have led to emissions of greenhouse gases, mainly carbon dioxide emissions from fossil fuels consumption, which contribute to long-term global warming and threaten to bring about global ecological catastrophes.

In 2010, the global average land and ocean surface temperature was 14.6°C, which was 0.9°C higher than in 1880 and 0.3°C higher than in 2000 (NASA 2011).

If global warming rises above 2°C (relative to the pre-industrial time), dangerous climate feedbacks may be triggered, leading to the release of more greenhouse gases from soil and ocean. For this reason, 2°C warming is generally considered by scientists as the “safe limit” beyond which global warming may be out of human control.

A 3°C warming would destroy the Amazon rainforest, leading to a further warming of 1.5°C. Southern Africa, Australia, Mediterranean Europe, and Western US would turn into deserts. Sea level could rise by 25 meters and billions of people could become environmental refugees.

With a 4°C warming, the melting of the Arctic permafrost could release massive amount of carbon dioxide and methane. Algae, the main carbon sinker in the ocean, would die out. The world is set for runaway global warming that could lead to additional temperature rises by several degrees.

If global warming rises to 5°C and above, much of the world would cease to be inhabitable and global human population could suffer a catastrophic decline. Table 4 summarizes the potential consequences of various degrees of global warming. It is not exaggerating to say that the very survival of the human civilization for centuries to come is at stake.

* * *

Without any further increase in greenhouse gases, the current level of greenhouse gases already implies a long-term warming of 2-4°C.

Note that Dr. Li, an economist, does not hesitate to point the finger at human economic activity as the cause of climate change.

Naomi Klein emphasizes this same point – that capitalism is the culprit – at The Nation: lowering global emissions as drastically and as rapidly as climate science demands can be done only by radically reordering our economic and political systems in ways antithetical to the “free market” belief system. Climate change is a consequence of unrestrained greed.

The fact that the earth’s atmosphere cannot safely absorb the amount of carbon we are pumping into it is a symptom of a much larger crisis, one born of the central fiction on which our economic model is based: that nature is limitless, that we will always be able to find more of what we need, and that if something runs out it can be seamlessly replaced by another resource that we can endlessly extract. But it is not just the atmosphere that we have exploited beyond its capacity to recover—we are doing the same to the oceans, to freshwater, to topsoil and to biodiversity. The expansionist, extractive mindset, which has so long governed our relationship to nature, is what the climate crisis calls into question so fundamentally. The abundance of scientific research showing we have pushed nature beyond its limits does not just demand green products and market-based solutions; it demands a new civilizational paradigm, one grounded not in dominance over nature but in respect for natural cycles of renewal—and acutely sensitive to natural limits, including the limits of human intelligence.

Climate change is a message, one that is telling us that many of our culture’s most cherished ideas are dangerous and destructive enough to not only imperil human civilization but to ravage the capacity of Earth to sustain life. Averting catastrophic climate change requires nothing less than a radical overhaul of our economy and society. Averting catastrophic climate change requires that the nations of the world abandon their obsession with economic growth and instead focus, above everything else, on slashing fossil fuel consumption.

Beginning like, now. Not next week, next year, next election, next congress, next climate conference. Now.

Fat chance of that happening.

A draft summary of an international climate report says that freakish weather disasters — like the October snowstorm in the northeast U.S. and the record floods in Thailand and other Southeast Asian countries — are already occurring more often and that the frequency of extreme  weather events will to continue to increase, at a huge cost.

Jeff Masters at WunderBlog describes the multi-billion dollar damage from the October snowstorm . . .

It’s time to add another billion-dollar weather disaster to the growing 2011 total of these costly disasters: the extraordinary early-season Northeast U.S. snowstorm of October 29, which dumped up to 32 inches of snow, brought winds gusts of 70 mph to the coast, and killed at least 22 people. Not since the infamous snow hurricane of 1804 have such prodigious amounts of October snow been recorded in New England and, to a lesser extent, in the mid-Atlantic states. Trees that had not yet lost their leaves suffered tremendous damage from the wet, heavy snow. Snapped branches and falling trees brought down numerous power lines, leaving at least 3 million people without electricity. The damage estimate in Connecticut alone is $3 billion, far more than the damage Hurricane Irene did to the state. Hundreds of thousands still remain without power a week after the storm, with full electricity not expected to be restored until Monday.

. . . and reports that 2011 has already set a new record for the number of billion dollar plus events, with nearly two months to go before the end of the year:

The October 29 snow storm brings the 2011 tally of U.S. billion-dollar weather disasters to fourteen, thoroughly smashing the previous record of nine such disasters, set in 2008.

Joseph Romm at Climate Progress charts the increase in billion dollar events over the last thirty years.

The IPCC report, to be issued in a few weeks, predicts costs will rise and some locations will become “increasingly marginal as places to live.”

Global warming isn’t only about subtle changes in daily average temperatures. It’s also about the increasing frequency of severe climate-related events that cause economic damage and kill people.

A new study published in Nature Geoscience by Ian Joughin and Richard B. Alley titled Stability of the West Antarctic ice sheet in a warming world reports recent observations by satellite show substantial mass loss from the West Antarctic ice sheet (WAIS).

Losses range from 100 to 200 gigatonnes per year, the equivalent to 0.28 to 0.56 mm per year sea-level rise – and the rate is increasing.

This excerpt is from the abstract:

Ice sheets are expected to shrink in size as the world warms, which in turn will raise sea level. The West Antarctic ice sheet is of particular concern, because it was probably much smaller at times during the past million years when temperatures were comparable to levels that might be reached or exceeded within the next few centuries. Much of the grounded ice in West Antarctica lies on a bed that deepens inland and extends well below sea level. Oceanic and atmospheric warming threaten to reduce or eliminate the floating ice shelves that buttress the ice sheet at present. Loss of the ice shelves would accelerate the flow of non-floating ice near the coast. Because of the slope of the sea bed, the consequent thinning could ultimately float much of the ice sheet’s interior. In this scenario, global sea level would rise by more than three metres, at an unknown rate.

The study’s authors suggest loss of the large ice shelves by atmospheric or oceanic forcing would probably lead to collapse of the bulk of the marine ice sheet. Temperature predications for 2100 approach the thresholds of ice-shelf viability in many simulations.

With CO2 emissions increasing by a record amount in 2010, temperatures by the end of the century are likely to be at the top end of or even exceed IPCC predictions. Meeting the 2° target the IPCC warns is necessary to avert dangerous climate change depends on limiting atmospheric CO2 to no more than 450 ppm. We are a little below 400 parts per million now – and heading higher. Recent research has found that the WAIS collapsed and rebuilt multiple times matching the cycle of Northern Hemisphere’s pattern of glaciation and glacier retreat – collapsing much more frequently when atmospheric CO2 hit 400ppm.

Sea level rise is now going up about 3.5 centimeters per decade. A collapse of the marine ice sheet in West Antarctica would raise sea levels by more than three meters over the course of several centuries or less – in the past, sea levels have risen at a speed of up to one meter per 20 years.

It’s bad enough that the Greenland ice sheet is melting: Greenland setting a new melt record in 2010, and Greenland melting in 2011 well above average with near-record mass loss. Now we may be witnessing the start of the destabilization of the WAIS.

Seth Borenstein of the Associated Press reports that greenhouse gases in the atmosphere are increasing faster than the worst case scenario outlined just four years ago in the IPCC’s 4th Assessment Report:

The global output of heat-trapping carbon dioxide jumped by the biggest amount on record, the U.S. Department of Energy calculated, a sign of how feeble the world’s efforts are at slowing man-made global warming.

The new figures for 2010 mean that levels of greenhouse gases are higher than the worst case scenario outlined by climate experts just four years ago.

Humans emitted about 564 million more tons (512 million metric tons) of carbon into the atmosphere in 2010 than it did in 2009 – an increase of 6%. Joseph Romm at Climate Progress posts these graphics.

China, the United States, and India are the world’s top producers of greenhouse gases. While the U.S. dithers and does nothing to stop global warming, the power to do so has slipped out of our hands. Earth’s fate now lies largely in the hands of others.

Emissions in developing countries are rising very rapidly and are projected to continue doing so. For example, between 1990 and 2009, among the top 5 emitting countries, China increased its per capita emissions by over two and a half times and India doubled them.

The demand for coal in India is expected to increase rapidly in the future, dominated mainly by the power sector as India’s government aims to double power generation over the next decade. India is currently the third largest producer of coal in the world; and India’s coal imports, which totaled 55 million tons in 2010, are expected to rise to 186 million tons by 2014 and to soar to ~300 million tons by 2016. China’s coal consumption rose to 2.28 billion metric tons of coal in the first nine months of 2011, up 10.3% from 2010. China is projected to more than double its consumption of coal by 2035.

OPEC forecasts that the use of all fossil fuels will continue to rise – with the burning of coal to more than double by 2035:

Raymond Pierrehumbert at RealClimate sums up all you ever really need to know about CO2 emissions and climate:

• The peak warming is linearly proportional to the cumulative carbon emitted
• It doesn’t matter much how rapidly the carbon is emitted
• The warming you get when you stop emitting carbon is what you are stuck with for the next thousand years
• The climate recovers only slightly over the next ten thousand years
• At the mid-range of IPCC climate sensitivity, a trillion tonnes cumulative carbon gives you about 2C global mean warming above the pre-industrial temperature.

Pierrehumbert notes we have already emitted about half the trillion-ton figure, so our whole future allowance is another 500 gigatonnes – assuming Earth herself doesn’t kick in. Nehring (2009) estimates that known global economically recoverable coal amounts to 846 gigatonnes, based on 2005 prices and technology. That’s ~634 gigatonnes of carbon, which all by itself is more than enough to bring us well past “game-over.” Proved reserves of conventional oil add up to ~139 gigatonnes C, proved natural gas reserves another ~100 gigatonnes C – and these two energy reserves are so valuable and easily accessible that it’s probably inevitable they will get burned. The carbon associated with the Athabasca oil sands deposit adds up to about 230 gigatonnes; estimates of how much of that will ultimately be economically recoverable vary from 10% to 70%.

And Earth herself is starting to kick in. Drying of northern wetlands has led to much more severe peatland wildfires and nine times as much carbon released into the atmosphere, according to new research led by University of Guelph professor Merritt Turetsky:

Russia, Indonesia and Canada all have abundant peatlands, but they also have been hotspots for intense peat fires in the past decade. Our study shows that when disturbance lowers the water table, that resistance [to fire[ disappears and peat becomes very flammable and vulnerable to deep burning. * * * Currently, peatlands are considered important global stores for carbon. But we’ve shown that human disturbance or climate-induced drying can switch peatlands from sinks to potentially huge sources of carbon, with losses associated with severe burning far outweighing long-term rates of sequestration.

And then there's the shocking conclusion from the study “Amount and timing of permafrost carbon release in response to climate warming” in Tellus by NOAA and the National Snow and Ice Data Center (NSIDC):

The thaw and release of carbon currently frozen in permafrost will increase atmospheric CO2 concentrations and amplify surface warming to initiate a positive permafrost carbon feedback (PCF) on climate. . . [Our] estimate may be low because it does not account for amplified surface warming due to the PCF itself. . . We predict that the PCF will change the arctic from a carbon sink to a source after the mid-2020s and is strong enough to cancel 42-88% of the total global land sink. The thaw and decay of permafrost carbon is irreversible and accounting for the PCF will require larger reductions in fossil fuel emissions to reach a target atmospheric CO2 concentration.

There are ~1,672 billion tonnes of carbon equivalent trapped in the form of methane in the Arctic permafrost, about twice as much carbon as currently contained in the atmosphere. Methane is 25 times as potent a heat-trapping gas as CO2 over a 100 year time horizon – but 72 times as potent over 20 years.

Even the International Energy Agency is warning time is running out to avert catastrophic climate change. Fatih Birol, the agency’s chief economist, says he’s not optimistic that anything will be done.

While humans continue to fiddle and burn, Earth’s carbon cycle is slipping beyond human ability to control.

Bad news: a new study finds that the prospects for avoiding dangerous global warming are bleak, indeed.

In the study, titled Emission pathways consistent with a 2°C global temperature limit, the team of scientists reanalyzed a large set of previously published emission scenarios based on integrated assessment models. They found that in the set of scenarios with a ‘likely’ (greater than 66%) chance of staying below 2°C, emissions peak between 2010 and 2020 and fall to a median level of 44 Gt of CO₂ equivalent in 2020 (compared with estimated median emissions across the scenario set of 48 Gt of CO₂ equivalent in 2010).

Current climate models show if the increase in average global temperatures is to be kept below 2°C (3.6°F), emissions must not only peak by 2020, emissions must fall by almost 10% by 2020  – and then continue to fall rapidly to well under half of current emissions by 2050.

Climate scientist Neil Edwards commented on the study’s findings:

The alarming thing is very few scenarios give the kind of future we want.

The International Energy Agency (IEA) recently announced global CO₂ emissions decreased for the first time since 1990, due to the 2008-2009 economic crisis – but warned, don’t expect a trend. A large rebound is anticipated in 2010. (Note: a report published by the European Commission’s Joint Research Centre and PBL Netherlands Environmental Assessment Agency found that global carbon dioxide (CO₂) emissions increased by more than 5% in 2010, reaching an all-time high.)

The IEA’s findings are contained in a free document that contains highlights from CO₂ Emissions from Fuel Combustion 2011, an IEA statistics publication which will be released in November 2011. The full document, which contains all the latest information on the level and growth of CO₂ emissions, is being released to inform the upcoming UN climate negotiations in Durban. Key findings include:

1. Two-thirds of global emissions for 2009 originated from just ten countries, with the shares of China and the United States far surpassing those of all others (combined, these two countries alone produced 41% of the world’s CO₂emissions).
2. Between 1990 and 2009, CO₂ emissions from the combustion of coal grew from 40% to 43% and natural gas from 18 to 20%, while CO₂ emissions from oil fell from 42% to 37%.
3. Two sectors – electricity and heat generation and transport – produced nearly two-thirds of global CO₂ emissions in 2009, up from 58% in 1990.

In their study, the climate scientists found only three of the 193 scenarios examined would be very likely to keep the warming below the danger level – and all of those require heavy use of energy systems that actually remove greenhouse gases from the atmosphere. That would require, for example, both creating biofuels and storing the carbon dioxide from their combustion in the ground. Edwards put it this way:

What we need is at the cutting edge. We need to be as innovative as we can be in every way.

In the statement quoted above, Edwards is assuming that the objective is to preserve the energy-intensive economic growth paradigm. But the paradigm is the problem. Every day it is becoming increasingly clear that cutting edge technology and innovation are not the answer.

One example: many Oregonians across the political spectrum, including Governor John Kitzhaber, have promoted forest biomass as a energy source, thinking woody debris from thinning, brush clearing and removing dead trees could help the state meet its renewable energy goals while at the same time restoring forest health and providing jobs in rural communities. But not so fast, say OSU researchers: managing forests for biofuel production will increase carbon dioxide emissions from the forests by at least 14%. The OSU press release quotes co-author Beverly Law:

Until now there have been a lot of misconceptions about impacts of forest thinning, fire prevention and biofuels production as it relates to carbon emissions from forests. If our ultimate goal is to reduce greenhouse gas emissions, producing bioenergy from forests will be counterproductive. Some of these forest management practices may also have negative impacts on soils, biodiversity and habitat. These issues have not been thought out very fully.

Looking to technology and innovation to enable humans to continue to pursue the economic growth that is consuming the very ecosystems that sustain us is just the denial of an addict. What is necessary is acceptance: growth is destructive and must be reversed. We must welcome and embrace the collapse of our current economic system, and learn to live within an economic system that conserves rather than consumes the larger systems of which it is a part.

Global carbon dioxide (CO2) emissions increased by more than 5% in 2010 and reached an all-time high in 2010, according to a report published by the European Commission’s Joint Research Centre and PBL Netherlands Environmental Assessment Agency.  CO2 emissions totaled 33 billion tonnes in 2010 – and have increased by 45% from 1990 (the base year for the Kyoto Protocol) to 2010.

While emissions from OECD countries have been decreasing, emissions from developing countries – especially China and India – have been soaring.

Atmospheric CO2 levels now exceed 390 ppm, far above the 350 ppm which could trigger catastrophic and irreversible climate change. Methane levels have begun to increase more rapidly, too, as seen in this chart from NOAA.

Increased radiative forcing is already having climate impacts, here in the U.S.

Impacts include more than just high temperatures. As Joseph Romm says, global warming means Hell and high water.

During 2011 to-date, extreme precipitation amounts have been present across the southern and the northeastern United States. Louisiana, New Mexico, and Texas all had their driest January-August periods on record, while Connecticut, New Jersey, New York, Ohio, and Pennsylvania were record wet during the same period.

Washington and Oregon were the only states across the lower 48 to have below-average summer temperatures.

Extreme weather isn’t helping global food prices. Food prices remain near all-time highs, according to the United Nations Food and Agricultural Organization.

The FAO Food Price Index (FFPI) averaged 231 points in August 2011, nearly unchanged from July and 26 percent higher than in August 2010. The FFPI hit its all time high of 238 points in February.

This year’s warming-driven extreme weather- along with the conversion of agricultural land to biofuel production – is likely to help keep food prices high for a while longer.

Scientists at the University of Bremen are saying Arctic sea ice extent reached a new record low this year.

Alerting message from the Arctic: The extent the Arctic sea ice has reached on Sep. 8 with 4.240 million km2 a new historic minimum (Figure 1). Physicists of the University of Bremen now confirm the apprehension existing since July 2011 that the ice melt in the Arctic could further proceed and even exceed the previous historic minimum of 2007. It seems to be clear that this is a further consequence of the man-made global warming with global consequences. Directly, the livehood of small animals, algae, fishes and mammals like polar bears and seals is more and more reduced.

The University of Bremen’s ice map shows the Northwest and Northeast passages are simultaneously ice free
This happened for the first time in 2008 – it did not happen in 2007, the year that saw the record minimum ice extent.

The daily sea ice maps of the University of Bremen are based on observations of the Japanese microwave sensor AMSR-E, in orbit on board the NASA spacecraft Aqua since 2002. The institute receives the data from two servers in the US and Japan and produces the maps based on the ASI (ARTIST Sea Ice) algorithm using the 89 GHz channels of AMSR-E. Other retrieval algorithms like NASA Team or Bootstrap may find slightly different sea ice extent values.

To wit: the National Snow and Ice Data Center has just called the yearly minimum Arctic sea ice extent, finding it the second lowest in the satellite record.

Arctic sea ice appears to have reached its lowest extent for the year. The minimum ice extent was the second lowest in the satellite record, after 2007, and continues the decadal trend of rapidly decreasing summer sea ice.

Please note that this is a preliminary announcement. Changing winds could still push ice flows together, reducing ice extent further. NSIDC scientists will release a full analysis of the melt season in early October, once monthly data are available for September.

* * *

The last five years (2007 to 2011) have been the five lowest extents in the continuous satellite record, which extends back to 1979. While the record low year of 2007 was marked by a combination of weather conditions that favored ice loss (including clearer skies, favorable wind patterns, and warm temperatures), this year has shown more typical weather patterns but continued warmth over the Arctic. This supports the idea that the Arctic sea ice cover is continuing to thin. Models and remote sensing data also indicate this is the case. A large area of low concentration ice in the East Siberian Sea, visible in NASA Moderate Resolution Imaging Spectroradiometer (MODIS) imagery, suggests that the ice cover this year is particularly thin and dispersed this year.

The Japan Aerospace Exploration Agency (JAXA) also pegs 2011 as the second lowest year for Arctic sea ice extent.

If September 9 holds up as the date of minimum ice extent, that’s the earliest date of minimum extent in years – and earlier than the average date (September 10) over the period of satellite records, which began in 1979.

While the absolute sea ice extent values might vary slightly from one method to the other – and even the day of the absolute minimum might vary slightly – all methods find consistently that all minima since 2007 have been lower than all minima before, i.e. the last four minima (2007-2011) are the four lowest on record.

And there’s little doubt that 2011 saw new record for Arctic sea ice volume . . .

. . . and area.

Global warming and climate change have already come to the Arctic. The full consequences of this new reality have yet to be seen.

The National Snow and Ice Data Center (NSIDC) reports Arctic sea ice extent averaged for August 2011 reached the second lowest level for the month in the satellite record, tracking near the record lows of 2007.

Arctic sea ice extent will likely reach its minimum extent for the year sometime in the next two weeks. If ice stopped declining in extent today, it would be the second-lowest minimum extent in the satellite record.

Both the Northwest Passage and the Northern Sea route appear to be open – for the fourth consecutive year.

Sea ice is now almost completely gone from the channels of the Northwest Passage, with the exception of a small strip of ice across a stretch of the Parry Channel. The southern route (Amunden’s Route) is ice free. According to the Canadian Ice Service, sea ice extent in the western Parry Channel is now the lowest at this time of year since record keeping began in 1966 and very little multi-year ice remains.

The fabled Northwest Passage opened for the first time in 2007. Now, it’s become routine. In 2008 the Northwest Passage and the Northern Sea Route were open simultaneously for the first time. This, too, seems now to be the new normal.

This chart from the Japan Aerospace Exploration Agency (JAXA) shows sea ice area approaching the record low set in 2007.

The area of sea-ice cover can be defined in two ways, sea ice “extent” and sea ice “area.” Sea ice “extent” is defined as the areal sum of sea ice covering the ocean (sea ice + open ocean), whereas sea ice “area”  counts only sea ice covering a fraction of the ocean (sea ice only). Thus, the sea ice extent is always larger than the sea ice area.

A new study confirms the minimum summertime volume of Arctic sea ice fell to a record low last year (2010) – but this year has already broken that record, as seen in this PIOMASS graph from the University of Washington’s Polar Science Center.

The decline in volume is even more apparent from this graph posted at Neven’s Arctic Sea Ice blog.

Sea ice volume in 2011 is already below last year’s record low. 2011 has already seen a new record minimum volume – and the melt season is not yet over.

Imagery from the NSIDC Multisensor Analyzed Sea Ice Extent (MASIE) shows that the southern route of the Northwest Passage as well as the Northern Passage are now free of sea ice.

2011 is the fourth consecutive year – and the fourth time in recorded history – that both Arctic shipping routes have become open to navigation.

Arctic ice extent is declining at a brisk pace, but melt is slightly behind the pace set in 2007, the record low year – as seen in this image at the IJIS Web site provided by the Japan Aerospace Exploration Agency (JAXA).

The National Snow and Ice Data Center (NSIDC) reports weather conditions in late July spread the ice out, but that conditions are now again such that sea ice extent may decline rapidly:

During early summer, a high-pressure cell persisted over the northern Beaufort Sea, promoting ice loss. This weather pattern broke down toward the end of July, slowing ice loss but spreading out the ice pack, making it thinner on average. The weather has now changed again, bringing another high-pressure pattern. Winds associated with this pressure pattern generally bring warm temperatures, and tend to push the ice together and reduce overall extent. In the Kara Sea, the combination of a high-pressure cell with low pressure to the west has resulted in strong northward ice movement, pushing the ice pack away from the coast and reducing ice extent. The same weather pattern is also increasing the movement of ice out of Fram Strait, between Greenland and Spitsbergen.

Right now, there is a record divergence between area and extent, as Neven reports at Arctic Sea Ice Blog. The difference is often substantial, as can be seen by comparing the graph of sea ice extent, above, with that of sea ice area, below, posted by Joseph Romm at Climate Progress.

The ratio of sea ice area to sea ice extent is now at a record low, as seen in the graph below.

NSIDC also reports that Arctic sea ice volume is now showing record lows. Through July 20 this year, the ice surface was melting faster than the underside of the ice. As the Arctic days grow shorter surface melt will slow – but ocean waters warmed during the summer will continue to melt the ice from below, reducing ice thickness and extent into September.

The University of Washington’s Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) model projects that this year’s minimum volume in September will very likely finish below 2007, reaching a new record low volume.