Arctic "death spiral" leaves climate scientists shocked and worried

by Barry Saxifrage, Vancouver Observer, September 19, 2012

Graphic by Barry Saxifrge

A "radical shift" is plunging the Arctic Ocean towards an ice-free state for the first time in millions of years. One of the world's foremost ice experts, Professor Peter Wadhams of Cambridge University, calls it a "global disaster" that will cause such a big boost in global temperatures that even such extreme measures as geo-engineering need to be considered urgently.

Climate science has long understood that disappearance of summer sea ice in the Arctic would be a "tipping point" in the Earth's climate system, accelerating global temperatures and causing extreme weather and other climate changes far beyond the Arctic. Yet nearly every expert has been shocked by just how rapidly this "continent of ice" has been vanishing, and how dramatic the impacts have been already.

Climate scientists and ice experts are now using phrases like "unprecedented," "amazing," "extreme," "hard to exaggerate," "incredibly fast," "death spiral" and "heading for oblivion."

Arctic sea ice has been a permanent, year-round fixture of our planet since long beforeHomo sapiens first appeared on the savannas of Africa as a new species. Despite being robust enough to survive every change Mother Nature threw at it for millions of years, Arctic sea ice has proven to be shockingly vulnerable to a few decades of humanity's unrestrained fossil fuel pollution.  

The trillion tonnes of CO2 pollution that people have released into the atmosphere fromburning oil, coal and natural gas has acted like a blow torch on Arctic ice. A dozen pounds of Arctic sea ice has disappeared for every one pound of CO2 we have released. This highlights the incredible heating power of CO2 which pumps 100,000 times more energy into our climate than was given off when the oil, coal or natural gas was burned.

CO2 has been the "Energizer Bunny" of extreme weather, pumping energy into our climate non-stop for centuries.

As my the chart above shows, three-quarters of the "permanent", year-round sea ice in the Arctic has been cooked away in just 30 years. Over half of it has disappeared in just the last eight years. A vast expanse of ice larger than the European Union has vanished. What's left is half the area and only half as thick.

Now some ice experts are saying what remains could be gone in as little as ten years -- or even four.

Worse than worst case

This jaw-dropping acceleration of Arctic sea ice collapse is completely out-stripping theworst case scenarios of the UN International Panel on Climate Change (IPCC). The IPCC reports are the primary source of climate science used by world leaders, policy makers, businesses and citizens to decide the urgency and level of action needed.

The most recent IPCC report includes this graphic on the right. It predicts summer sea ice surviving long after most people alive today will have died of old age.

It is easier for decision makers to procrastinate on a difficult task if they don't think it will become critical for generations.

And sure enough, humanity has procrastinated badly in tackling the climate threat. The amount of fossil fuel CO2 pollution the world is pumping out every year is still increasing, even as extreme weather and climate shifts are accelerating.

The IPCC predictions come from a suite of the best global climate models at the time. Below is a chart showing the predictions of the IPCC global models used in their most recent report. For comparison I've added a bold orange line showing the best estimates -- based on multiple modes of observations -- for what has actually happened.

These IPCC models are off by many decades -- whole generations, in fact. New models are being developed for the next IPCC report. They have been described as "less bad"in some ways but they still fail to offer any better guidance than the old models on how quickly summer ice will vanish. At this rate the ice will be gone before we can we can build models to tell us that.

The orange "best estimate" values on the chart come from a University of Washington project called PIOMAS. For years many experts were sceptical of PIOMAS ice loss estimates because they were so extreme and because humans didn't have complete high quality data for ice volume. Could they be wildly wrong?

Unfortunately, the answer is no. Two years ago, the European Space Agency launched a satellite (CryoSat-2) specifically designed to very accurately measure sea ice volume. The results from the first two years have confirmed the PIOMAS estimates. Three quarters of the summer ice volume really seems to have vanished.

A recent CBC report on these CryoSat-2 results was blunt: "Arctic ice could vanish in 10 years, scientists warn … Arctic sea ice is melting at a pace so much faster than once thought that the latest projections say it might disappear by as soon as 2022."

Professor Wadhams, whose predictions of rapid ice loss have so far been among the most accurate, told the Guardian he thinks summer Arctic sea ice could vanish within four years.

Once again we are being caught off guard as the actual pace of climate change is unfolding far more rapid than the conservative IPCC estimates used by policy makers, businesses and citizens worldwide. These conservative estimates have encouraged a tepid policy response. Further encouraging foot-dragging on climate action has been a well-organized, well-funded campaign of fake climate skeptics attacking the science and scientists that sought to alert humanity to the need to act more quickly.

Just how badly have we dithered in removing climate pollution -- and the economic risk that goes with it -- from the global economy? Take a look:

 

The chart above shows the ever increasing amount of fossil fuel CO2 that humans are releasing each year. Not only are we pouring lots more fuel into global warming each year, we are also doing it at a rate that was considered a worst case scenario by the IPCC just a decade ago.

Clearly we have persuaded ourselves that climate damages would unfold slowly over a century or more. But now in the Arctic we have again drawn the short straw.

All that vanishing sea ice is amplifying global warming and extreme weather far beyond the Arctic. A series of global warming feedback loops --- outside of our direct control -- are emerging already. As one climate scientist put it: "What happens in the Arctic doesn’t stay in the Arctic."

As the meltdown continues the impacts are expected to get worse.

Here is a quick overview of some of the big, currently known, impacts...

Multiple feedback loops amplify global warming.

As the sea ice disappears, a series of interconnected feedback loops are significantly increasing global warming. The stronger these feedback loops grow, the faster and deeper our cuts in fossil fuel CO2 emissions will need to be to compensate.

 New sources of global warming include:

1. Albedo flip.
    Sea ice reflects sun's rays back into space keeping the planet cooler. As sea ice disappears the uncovered ocean absorbs this energy, making the planet hotter. One estimate says the extra heat gained equals the global warming from an additional 20 years of human CO2 pollution. 
   
2. Permamelt. As the Arctic rapidly heats up, the "permanently" frozen soils (permafrost) also have started to melt at any increasingly rapid pace. As permafrost thaws it releases methane and CO2 -- both potent greenhouse gases. A new study by University of Victoria climate scientist Andrew Weaver and others predicts that Canada's melting permafrost will accelerate global warming more than 0.5 C by the end of the century. That is about half the warming we still have left before most climate scientists predict dire impacts on humans.
   
3. Methane hydrates melting. Tremendous amounts of methane are frozen on the bottom of the Arctic Ocean. As water temperatures increase, the threat of large emissions of methane bubbling out of the sea grows. Climate scientist James Hansen of NASA says the melting of methane hydrates in the earth's past has triggered rapid global warming leading to major extinction events.
   
4. Dying forests. 
   Rapid warming is causing the entire western boreal forest to start dying faster than it is growing back according to recent research. This gigantic swath of landscape has shifted from an absorber of CO2 to an emitter of CO2 in recent years. This is creating a feedback loop where over-heating forests release CO2 that then over-heats the forests even more. Forest fires are also increasing in the boreal and arctic, releasing ever more CO2. Meanwhile, the voracious mountain pine beetle that has been unleashed by warming temperatures has already eaten half the pine trees in BC and across large areas of western North America. These dying pine forests are releasing huge amounts of CO2 into the atmosphere. Experts predict that with unchecked global warming the native pine beetles will expand in a few decades into the boreal forest and eat that forest down from coast to coast.
   
5. More fossil fuels to burn.
   The Arctic Ocean has huge quantities of oil and methane that humans have not yet been able to turn into CO2. The sea ice has kept us from extracting and burning them. Now, as the sea ice vanishes, a black gold rush is kicking in. Shell Oil just put the very first drilling rig in. Scrabbling for more carbon to burn in an over-heating Arctic reminds me of people smoking cigarettes through their tracheotomy hole. It might not be illegal, but piling on more of what caused a crisis is likely to end badly.
   
6. Vanishing spring snow cover. 
   One of the most dramatic but least discussed climate changes on our planet has been the rapid decline in our spring snow cover. Warmer temperatures are melting snow earlier each year. In fact the area of missing snow cover is much greater than thearea of missing sea ice. The snow cover is retreating northward at a rate of 60 km per year. This huge decline in snow cover is driving the same kind of global warming feedback loop as the vanishing sea ice. Instead of snow reflecting sunlight back into space in spring and summer, the snow-free land absorbs it, ratcheting up global temperatures.
   

More extreme weather

In addition to the global warming feedback loops mentioned above, the Arctic meltdown is also driving extreme weather in another surprising way -- by destabilizing the polar jet stream.

The polar jet stream is a huge river of air that circles the globe. It pushes and steers the storm systems across much of Canada, USA, Europe, Russia and northern Asia.

The speed of the jet stream is driven by the difference in air temperature between the Arctic and the tropics. This difference is shrinking as the vanishing sea ice pushes the Arctic to heat up faster than any place on earth. Similar to what happens when you remove a hot-tub cover, the removal of the sea ice cover allows heat from the water below to escape and warm the air above.

Measurements show the polar jet stream has been slowing down and getting "stuck" more easily. Weather patterns are staying stationary for longer periods. Also known as "blocking" patterns, this stuck weather phenomenon has been behind several of the worst extreme weather events, and crop failures, in recent years.

Sunny weather that gets stuck can turn into extreme heatwaves and drought, as seen in Russia, Europe and the USA recently. Rainy weather that gets stuck can turn into weeks of extreme rain and flooding as seen around the globe recently. Snowy weather that gets stuck can turn into "snowmaggedons".

Arctic ecosystems unravelling

The amplified warming in the Arctic is unravelling huge ecosystems. Animals that depend on summer ice like polar bears, walrus, seals and whales are struggling. Permfrost is collapsing, wave heights growing, shorelines eroding, sea level rising, wildfires increasing, temperature zones shifting, forests dying and a string of record-breaking storms pounding away on it all.

NASA satellite image of an unusually powerful and long lasting Arctic storm in August 2012.

Now what? More fossil fuel CO2?

With extreme weather increasing, crops failing and a series of nasty feedback loops accelerating in the Arctic it seems like a prudent time to stop throwing fuel -- fossil fuel CO2 -- on the climate fire.

In BC, the promising first steps towards removing carbon pollution -- and therefore carbon risk -- from our economy have faltered. The current Clark government is instead working to increase the amount of carbon flowing through the BC's economy. In addition they have frozen the carbon tax, exempted whole industries from paying it and are keeping most of our economy's carbon off the books.

Pumping ever more carbon into our economy, while ignoring most of it when making policy decisions, seems increasingly reckless. It increases the pace of climate change while also increasing our economy's exposure to carbon risk.  

This kind of wilful ignorance of accelerating risk didn't work out well for Enron, dot-com shareholders or American mortgage holders. In the end, unsustainable bubbles pop.

The rapidly destabilizing Arctic shows that we are already late in waking up to the carbon threats facing our climate and our economy.

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