Jumat, 06 Maret 2015

Save the Arctic sea ice while we still can!

The Arctic Ocean is coming close to complete summer meltdown, writes John Nissen - indeed it could happen as soon as September, triggering a severe deterioration in climate across the northern hemisphere. With fast-rising temperatures predicted in the coming decade, we must act now to save the Arctic, before it's too late.



By John Nissen

John Nissen: "Nothing has been said by the
IPCC. Nothing has been said in the
mainstream media. Nothing has been said
by the scientific community at large. This
is a terrible omission. It is quite scandalous."
Fossil fuel companies, and their supporters in government, seem blissfully unaware of the dangers ahead, threatening everybody on this planet.

The sea ice is declining far more rapidly than anyone expected. It is declining towards disappearance in summer months, yet the colossal negative impact of a low albedo Arctic has hardly been discussed. This is tragic because the whole situation could have been avoided with good leadership at negligible economic cost.

And as reported this week on The Ecologist, new scientific research indicates that the apparent 'pause' in global warming has, in fact, been no such thing. Instead the surplus heat - two Hiroshima bombs-worth a second - has simply been 'buried'
deep in the Pacific Ocean.

That's because of two important climate cycles, the Pacific Decadal Oscillation and the Atlantic Multidecadal Oscillation, whose operation has masked the warming. But soon they will tip the other way and the 'Big Heat' is set to begin - a five to ten year burst of rapid warming that will be most severe in the Arctic.

Commercial advantages for some ...

If you read the mainstream media, only the positive impact of a melting Arctic is mentioned: an Arctic ripe for exploitation.

Through not grasping the huge negative impact of a low albedo Arctic, the fossil fuel companies still appear entirely happy for the sea ice to disappear as quickly as possible - the sooner the better. Therefore they naturally resist any action to save the sea ice. In particular they don't want geoengineering deployed to cool the Arctic, because it might succeed in saving it!

Certain fossil fuel companies have already invested heavily in exploiting the vast store of oil and gas in the Arctic. These companies, and the governments who support them, are preparing for a bonanza when the sea ice disappears in summer: it will be so much easier and safer to extract the fossil fuel when the sea ice and freezing conditions have gone during summer months.

Furthermore, the disappearance of the sea ice will open up the Northwest Passage and the Northern Sea Route (formerly known as the Northeast Passage) to trade through summer months. So China and nations bordering the Atlantic (including the UK) are expecting to benefit enormously. Russia is investing heavily in ports and infrastructure to support the anticipated heavy traffic.

Various environment groups and the UK Environment Audit Committee have argued against drilling in the Arctic because they are concerned about oil spills and gas blow-outs which could ruin the local environment. They also seek to protect the wild life and Arctic ecosystem. But their arguing will be futile once the sea ice has gone in summer. It will be too late to protect the environment.

Environmentists have less concern about the opening up of the trade routes, because this will reduce CO2 emissions from transport of goods which at present have much longer journeys.

The Arctic bombshell is waiting to go off

While there is all this talk of exploiting the Arctic, little or nothing is said about the adverse effects of having an Arctic free of sea ice during summer months.

Nothing has been said by the IPCC. Nothing has been said in the mainstream media. Nothing has been said by the scientific community at large. This is a terrible omission. It is quite scandalous.

While most experts agree that there will come a time when the Arctic Ocean will be free of ice during summer months, there is no such agreement on the time-scale. Models suggest that it will take decades.

But observations of an exponential trend of sea ice decline suggest that this time could be within a decade. Scientific reports of especially rapid temperature rise in Alaska have also emerged. For example Barrow, Alaska, has experienced a 7°C temperature rise over 34 years, attributed to the decline in sea ice.

So what are the effects? During summer months, a vast area of reflective ice will have been replaced by open water, absorbing 90% of sunshine and warming the Arctic air above. It is clear that the Arctic will be warming much faster than at present - likely at over 2°C per decade.

As heat dissipates around the planet, there will be a huge contribution to global warming in the long term. Estimates put this at equivalent of 3.3 W/m2 (Flanner, 2011) or about twice the current warming from CO2.

But what are the immediate consequences of this super-rapid warming in the Arctic? At present we have an acceleration of three particular processes, affected by Arctic warming to date:
  • Firstly, we have a dramatic rise in Northern Hemisphere weather extremes, as the jet stream behaviour is disrupted.
  • Secondly we have an exponential increase in meltwater from the Greenland Ice Sheet, flowing through moulins on the surface of the ice into the sea and raising the sea level.
  • And thirdly we have a dramatic increase in methane emissions from the Arctic Ocean seabed.
As the temperature in the Arctic continues to increase, these processes will continue almost indefinitely. We can expect worsening Northern Hemisphere climate causing widespread crop failures; faster sea level rise causing progressive flooding of low-lying regions; and growing methane emissions leading to even more catastrophic global warming.

These are three immediate results of the switching on of heat as the Arctic Ocean enters the low sea-ice state. The combination will be devastating for all mankind - with mass starvation and mass migration liable to trigger a world war.

This is the terrifying bombshell. The bonanza will be short-lived, as the effects of a seasonally ice free Arctic Ocean begin to bite.

For a few billion dollars a year, we can save the Arctic

Something must be done to prevent the ocean entering this low-ice state. Therefore the Arctic must be cooled enough to save the sea ice.

The first moment at the end of summer that the sea ice finally disappears from the ocean is called the 'blue ocean event'. It is significant because it could mark the entry of the ocean into a permanent low-ice state for subsequent years - the point of no return. The point of no return could be a soon as next September.

By any ordinary standards, we have left it too late to cool the Arctic. But any reduction in the risk of passing the point of no return is worthwhile, when all our futures are at stake.

Fortunately researchers are increasingly confident that a stratospheric aerosol haze, produced from sulphur dioxide, SO2, could provide significant cooling of the Arctic for modest expenditure of the order of a few billion dollars per year.

This type of cooling could be replaced by cloud brightening using ultra-fine seawater droplets when the technology is ready for large-scale deployment within a year or two.

There should be no significant negative economic impact from this action, except that the resources in the Arctic become frozen assets. But they should be frozen assets in any case if global warming is to be kept below 2°C, according to a recent paper.

There should be positive political impact, because governments will be working together in a common cause to protect their own citizens and all the citizens of the world. The fossil fuel industry has to be persuaded that preserving the Arctic sea ice is essential for the future of themselves and their stakeholders.

Objections from the anti-geoengineering lobby have to be overcome, because we have no other realistic option to reduce the colossal risk of passing a point of no return this September.



John Nissen is Chair of the Arctic Methane Emergency Group
This post earlier appeared in The Ecologist

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