The National Snow and Ice Data Center says the Arctic sea ice melt season has finally begun:

On March 18, 2012, Arctic sea ice extent reached its annual maximum extent, marking the beginning of the melt season for Northern Hemisphere sea ice. This year’s maximum extent was the ninth lowest in the satellite record.

Sea ice appeared to have reached its maximum extent earlier in the month on March 6 – but an unexpected change in Arctic weather lead to a late-season surge.

The maximum this year was very late compared to recent years, occurring 12 days later than the 1979 to 2000 average date of March 6.

• March 6th 2005: 13.46
• March 11th 2006: 13.36
• February 26th 2007: 13.32
• March 11th 2008: 13.89
• March 2nd 2009: 13.85
• March 7th 2010: 13.81
• March 8th 2011: 13.14
• March 20th 2012: 13.70

This year’s maximum ice extent was 15.24 million square kilometers (5.88 million square miles), 614,000 square kilometers (237,000 square miles) below the 1979 to 2000 average of 15.86 million square kilometers (6.12 million square miles). This year’s maximum was the ninth lowest in the satellite record. Last year (2011) was the lowest maximum on record at 14.64 million square kilometers (5.65 million square miles). Including this year, the nine years from 2004 to 2012 are the nine lowest maximums in the satellite record.

Sea ice extent in February and March tends to be quite variable, because ice near the edge is thin and often quite dispersed. The thin ice is highly sensitive to weather, moving or melting quickly in response to changing winds and temperatures, and it often oscillates near the maximum extent for several days or weeks, as it has done this year. NSIDC’s call includes this caveat:

As of March 23, ice extent has declined for five days. However, there is still a chance that the ice extent could expand again.

Why should we care about what’s happening in the Arctic? Because the Arctic is the “canary in the coal mine”, warming faster than anyplace else on Earth.

The warming Arctic is already affecting Earth’s weather. The erratic weather and extreme weather events seen over last few years are merely a foretaste of what’s in store for the future. Jennifer A. Francis, a Rutgers University climate researcher, is quoted in the New York Times:

The question really is not whether the loss of the sea ice can be affecting the atmospheric circulation on a large scale. The question is, how can it not be, and what are the mechanisms?

Climate mechanisms in the Arctic are a major driver of weather in the northern hemisphere, including not only “über-extreme” weather events but also the weird and unpredictable weather affecting crops and livelihoods at home, like here in Oregon. What happens in the Arctic directly impacts us in our daily lives.

Massive die-offs of oyster larvae in the Pacific Northwest show ocean acidification from an excess of CO2 emissions has already begun.

In Netarts Bay, from 2006 to 2008, oyster larvae began dying dramatically. Elizabeth Grossman, in an article in Yale Environment 360, quotes Netarts Bay hatchery owner Mark Wiegard:

Historically we’ve had larvae mortalities [usually related to bacteria] . . . My wife sent a few samples in and Hales [Burke Hales, a biogeochemist and ocean ecologist at Oregon State University] said someone had screwed up the samples because the [dissolved CO2 gas] level was so ridiculously high.

Taylor Shellfish Hatchery in Washington, the country’s largest producer of farmed shellfish and one of the largest oyster producers, has also reported dramatic losses.  Hood Canal has some of the Pacific Northwest’s highest levels of ocean acidification. Taylor’s hatchery there experienced the loss of about three-quarters of its oyster larvae, losses which are now being mitigated by buffering the high acidity.

Wild oyster beds in the Pacific Northwest are suffering, too.  Wild oysters in Willapa Bay,  Puget Sound, and off the east coast of Vancouver Island have seen reproductive failure because acidic waters have prevented oyster larvae from forming shells. Acidic water sometimes kills oyster larvae outright, so that they fail to survive past the egg stage. At other times the eggs hatch; but the larvae, stressed as they try to forms their first shells, fail after a week or two.

The water now washing ashore in Oregon and Washington actually absorbed its CO2 30 to 50 years ago. Oceans absorb about 50% of the CO2 released by burning fossil fuels. Since then, emissions have been rising even more dramatically.

Ocean acidity has increased approximately 30% since the Industrial Revolution and is on track to be 150% more acidic by the end of the century than it has been for 20 million years. Ocean acidification depletes seawater of the compounds that organisms need to build shells and skeletons, impairing the ability of corals, crabs, sea stars, sea urchins, plankton and other marine creatures to build the shells they need to survive. Ocean acidification could destroy all of the globe’s coral reefs by 2050 and threatens the entire marine ecosystem.

Arctic sea ice is disappearing much faster and more dramatically than expected, according to new research by the Norwegian Polar Institute (NPI). Consequently, the Arctic Sea could be free of ice in the summer in ten years, rather than the 50 to 100 years previously estimated.

Here’s the abstract from “Thinning of Arctic sea ice 1990-2010 as observed by upward looking sonars – or why the Arctic Ocean could be ice free in summer in less than ten years“:

Time series of sea ice thickness observed in Fram Strait by moored sonars show a 35 percent reduction in multiyear (MY) modal ice thickness since 2005. The MY mode reflects the thickness of level ice which has survived at least one melt season, and is hence a reflection of the thermodynamic equilibrium. During the 1990s the late winter MY modal thickness was 3.4+-0.4 m. Following excessive export of MY ice during the winter of 2005, late winter MY modal ice thickness dropped to 2.2 +-0.1 m, which persisted until the end of our record in 2010. The reduced MY modal ice thickness is a result of the Arctic sea ice cover entering a new state, where dynamic and thermodynamic effects appear to have combined to shift the equilibrium towards thinner ice.

This new state includes a dramatic reduction in the fraction of ridged sea ice, compared to the 1990s. The vast fields of ridged ice thicker than 5 m, constituting 28 percent of the winter Arctic sea ice cover during the 1990s, is nearly gone. At the end of winter in 2010, ice thicker than 5 m constituted only 6 percent of the total ice mass observed. The combined effect on late winter mean ice thickness is a reduction from 4.3+-0.4 m during the 1990s to a record low value of 2.0 m in late winter 2010. We speculate that increased ocean heat flux plays an important role in the thinning of the thick ice. With the thickest ice nearly gone and the MY level ice thicknesses close to thicknesses typical for first year sea ice, we are approaching a state where favorable conditions could melt most of the Arctic sea ice cover during one summer. 

This graphic provided by the U.S. Navy shows how little older, thicker ice is left – just a thin band along the northern edge of the Arctic Archipelago and the north coast of Greenland.

The graphic here is animated – you can watch the older ice flowing out of the Arctic Sea through the Fram Strait.

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.

The National Snow and Ice Data Center (NSIDC) reports average Arctic sea ice extent for July 2011 was the lowest level for the month since satellite records began in 1979.

Ice loss slowed substantially over the latter half of the month as the weather changed. A high-pressure cell centered over the northern Beaufort Sea broke down and a series of low-pressure systems moved over the central Arctic Ocean, bringing cooler conditions and likely pushing the ice apart into a thinner but more extensive ice cover.

Daily Arctic sea ice extent as of August 2, 2011, along with daily ice extents for previous low-ice-extent years. Light blue indicates 2011, dashed green shows 2007, dark blue shows 2010, purple shows 2008, and dark gray shows the 1979 to 2000 average. The gray area around the average line shows the two standard deviation range of the data.

In the first week of August, with a month or more to go in the melt season, Arctic sea ice area has already dropped below not just the year-to-date values, but the annual low points of any satellite-era year before 2007.

Shipping routes in the Arctic have less ice than usual for this time of year, and more of the Arctic’s oldest ice has disappeared.

Sea ice concentration (left) and ice age (right) over the Arctic Ocean. In the Beaufort Sea off the coast of Alaska, ice has melted back to the edge of a tongue of older, thicker ice. In the "Ice Age" image, red shows ice 5 years old and older, green shows 4-year-old ice, light blue shows 3-year old ice, dark blue shows second-year ice, and purple shows first-year ice.

Over the past few weeks, the sea ice edge has retreated from the shores of Siberia and Eurasia, opening up much of the Northern Sea Route – the shipping lane that runs along the Eurasian Arctic coast from Murmansk on the Barents Sea, along Siberia, and through the Bering Strait. Some ice remains, particularly in the East Siberian Sea, but the reduced ice cover in the region has already made the route feasible this year. Taking advantage of the early retreat of sea ice in the Kara and Barents seas, the tanker Perseverance set sail on June 29, 2011 from Murmansk, Russia, aided by two icebreakers; and completed the passage on July 14. The company plans to send six to seven more ships through the Northern Sea Route this summer.

On the other side of the Arctic, the Northwest Passage is still choked with ice. However, ice loss in the Northwest Passage is well ahead of average, nearly matching last year when sea ice in the Parry Channel (the northern part of the Northwest Passage) reached the lowest levels in records dating back to 1968.

In an unusual mid-month update, the National Snow and Ice Data Center (NSIDC) reports Arctic sea ice is now disappearing faster than in 2007, the year that saw a record low for sea ice extent at the end of the melt season in September:

Arctic sea ice extent declined at a rapid pace through the first half of July, and is now tracking below the year 2007, which saw the record minimum September extent. The rapid decline in the past few weeks is related to persistent above-average temperatures and an early start to melt. Snow cover over Northern Eurasia was especially low in May and June, continuing the pattern seen in April.

To date in July, air temperatures over the North Pole (at the 925 millibar level, or roughly 1,000 meters or 3,000 feet above the surface) were 6 to 8 degrees Celsius (11 to 14 degrees Fahrenheit) higher than normal.

NSIDC explains why the early ice melt is significant:

When sea ice starts to melt in spring, small ponds known as melt ponds form on its surface. The small pools create a darker surface (a lower albedo) that fosters further melt. How early sea ice melt starts is one indicator of how much the ice will melt in a given year. New research by Don Perovich and colleagues shows that an early start to sea ice melt increases the total amount of sunlight absorbed through the melt season.

Arctic sea ice volume continues to plunge to record lows, too . . .

. . . as older, multi-year ice is replaced by younger, thinner ice more susceptible to melting in the summer.

The Arctic’s death spiral continues.

A new report just released by the International Program on the State of the Oceans finds the condition of the oceans is declining far more rapidly than even pessimists had expected. It’s bad enough that many marine species — including those that make coral reefs — could be extinct within a generation. Humans may have set Earth on track for a sixth mass extinction event.

The key findings of the International Earth system expert workshop on ocean stresses and impacts Summary Report should be enough to shake any cognizant being out of their lethargy:

• Human actions have resulted in warming and acidification of the oceans and are now causing increased hypoxia – symptoms that indicate disturbances of the carbon cycle associated with each of the previous five mass extinctions on Earth.
• The speeds of many negative changes to the ocean are near to or are tracking the worst-case scenarios from IPCC and other predictions. Consequences matching those predicted under the “worst case scenario” include decrease in Arctic Sea Ice, melting of the Greenland and Antarctic ice sheets, sea level rise, and release of trapped methane from the seabed.
• The magnitude of the cumulative impacts on the ocean is greater than previously understood, as interactions between different impacts can be negatively synergistic.
• Timelines for action are shrinking. Delays will mean increased environmental damage with greater socioeconomic impacts.
• Resilience of the ocean to climate change impacts is severely compromised by the other stressors from human activities, including fisheries, pollution and habitat destruction.
• Ecosystem collapse is occurring as a result of both current and emerging stressors including chemical pollutants, agriculture run-­off, sediment loads and over-­extraction of many components of food webs.
• The extinction threat to marine species is rapidly increasing due to overexploitation, habitat loss, and, increasingly, climate change.

But don’t count on any response from our political or economic elites, other than wanton disregard. They have proved to not be cognizant beings.

A press release quotes Dr. Alex Rogers, Scientific Director of the International Programme on the State of the Ocean (IPSO), which convened the workshop:

The findings are shocking. As we considered the cumulative effect of what humankind does to the ocean the implications became far worse than we had individually realized. This is a very serious situation demanding unequivocal action at every level. We are looking at consequences for humankind that will impact in our lifetime, and worse, our children’s, and generations beyond that.

Co-author Dan Laffoley issued a call for action:

The world’s leading experts on oceans are surprised by the rate and magnitude of changes we are seeing. The challenges for the future of the ocean are vast, but unlike previous generations we know what now needs to happen. The time to protect the blue heart of our planet is now, today and urgent.

The chances of any significant action being taken are precisely zero. The sad reality is the ocean and its ecosystems are doomed to succumb to a constantly bombardment of multiple attacks.

Dan Allen at Energy Bulletin scathingly observes that humans have proved to be less than rational:

[A]ny sane society . . . when faced with such an overwhelming abundance of scientific evidence, would be gnashing its collective teeth and running for the powerdown-exits en masse at this point. No sane society would ignore the screaming warnings of every single Earth system. No sane society would knowingly doom their children and grandchildren to misery and starvation. No sane society would stand by and do NOTHING — NOT ONE DAMN THING!! — while their very life-support systems eroded away before their eyes.

But we are surely not sane.

Political solutions have failed us, are failing us, and will certainly continue to fail us. The only option we have – to slam on the brakes and to stop burning coal, tout de suite – won’t be undertaken voluntarily; to think otherwise is delusional. Climate catastrophe is where we are. As Allen says, that’s the bed we’ve made:

So, sadly, at this late hour, we just flat-out NEED the dark angel of economic collapse to swoop down onto the stage, ‘Deus ex Machina’ style, and save the day.

God help us.

Pray for the collapse of the global industrial economy. And do what you can to begin fashioning a replacement.

The National Snow and Ice Data Center (NSIDC) reports sea ice reached its maximum extent on March 7 this year. Sea ice extent on this date tied for the lowest winter maximum extent in the satellite record. Arctic sea ice extent for the month of March 2011 was the second lowest in the satellite record.

The amount of older, thicker ice has increased slightly over last year. Older ice that has survived several summer melt seasons tends to be thicker, while newer ice is thinner and more vulnerable to melt in summer. The trend of spring ice cover becoming increasingly dominated by younger and generally thinner ice (because of strong summer melting reducing the amount of ice surviving into winter) remains striking.

There is still almost none of the oldest ice, older than four years old, that used to dominate much of the Arctic Ocean.

Scientists have found that the freshwater content of the upper Arctic Ocean has increased by about 20% since the 1990s. This corresponds to a rise of approximately 8,400 cubic kilometers and has the same magnitude as the volume of freshwater annually exported on average from this marine region in liquid or frozen form.

Around 10% of the global mainland runoff flows into the Arctic via the enormous Siberian and North American rivers in addition to relatively low-salt water from the Pacific. This freshwater lies as a light layer on top of the deeper salty and warm ocean layers and thus extensively cuts off heat flow to the ice and atmosphere. Changes in this layer are therefore major control parameters for the sensitive heat balance of the Arctic. The scientists expect that the additional amount of freshwater in the near-surface layer of the Arctic Ocean will flow out into the North Atlantic in the coming years. The amount of freshwater flowing out of the Arctic influences the formation of deep water in the Greenland Sea and Labrador Sea and thus has impacts on global ocean circulation.

The study, by researchers of the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven, Germany, is published in the journal Deep-Sea Research.