As James Hansen in this video says "We DO have an emergency". He talks about climate tipping points such as the loss of summer Arctic sea ice amplifying the release of methane in permafrost on tundra landscapes and methane hydrates in the shallow East Siberian and Alaskan continental shelves. These tipping points have catastrophic consequences for our climate.
Climate tipping points are processes we don't want to launch. They are climate feedback mechanisms which take any sort of control over global warming out of our hands and threaten widespread species extinction and threaten the viability of civilisation and perhaps even human survival.
They could act either as slowly accelerating feedback mechanisms which keep increasing global temperatures by several degrees or a relatively sudden 'methane bomb' in which a large abrupt release of methane occurs. In either case, it would be disastrous for human civilisation, although in the first instance we would be like the frog in a pot of water being brought slowly to the boil, not having the where-with-all to notice the incremental changes before it is way too late.
Related: The United Nations Environment Program released a scientific report - Policy Implications of Warming Permafrost - at the Doha climate talks highlighting the threat from methane from melting permafrost. See Methane and CO2 in thawing Arctic permafrost a climate tipping point | Radio Ecoshock: Climate: Arctic Thermostat Blows Up , particularly the Interview with Paul Beckwith (MP3) from the Arctic Emergency Methane Group
Here is James Hansen from the video:
"It's hard for the scientists to make the public realise that we do have an emergency. We will certainly get those effects. We can't say exactly what date an ice sheet is going to collapse, but we know that the ice sheets will collapse and sea level will go up many metres. If we burn all the fossil fuels then we will certainly cause the methane hydrates to eventually come out and cause several degrees more of warming, and it's not clear that civilisation could survive that extreme climate change." said James Hansen. "you don't want to push the system past those kind of tipping points, because if we do we lieave a situation for our children and grandchildren that will be out of control; they won't be able to stop it."
David Wasdell is a UK based expert on feedback dynamics of climate change. From the video he says:
"The question about a tipping point is also profoundly important. Not only do the feedbacks accelerate climate change, but they reach the point where the power of the feedback overwhelms our capacity to intervene and damp the system's behaviour. At that point we move into runaway change, over which we have no further control. Once we pass that threshold we precipitate a mass extinction event similar to the five we have experienced in geological time. With the potential to wipe out 80-89% of life on this earth. We don't want to go there. We have to work very fast to prevent the system moving in an accelerated and destabilised process that pushes us beyond that critical threshold, the point of no return."
Arctic climate scientist Natalia Shakhova has been researching methane release from permafrost and methane hydrates from sediments for several years, particularly on the East Siberian Continental shelf. She says in the video:
"The total amount of methane in the current atmosphere is about 5 Gt. The amount of carbon preserved in the form of methane in the East Siberian Arctic Shelf is ~ from hundreds to thousands Gt. What divides this methane from the atmosphere is a very shallow water column and a weakening permafrost, which is losing its ability to serve as a seal. This area is very seismically and tectonically active and there was some investigation that the tectonic activity is increasing.
You can read an interview with Natalia Shakhova published January 2012 on Skeptical Science: Arctic methane outgassing on the E Siberian Shelf part 2 - an interview with Dr Natalia Shakhova
More and more climate scientists, such as those in the Arctic Methane Emergency Group, and many concerned citizens are publicly calling for greater action in combatting this climate emergency. Certainly most climate scientists believe that the next eight years are critical for limiting climate change.
There is substantial risk in underestimating the climate feedbacks, tipping points that we may trigger if we continue on with business as usual, or only take minimal ineffectual action (as currently most countries are doing). We appear to be not adequately factoring in those risks in the science policy which Government decisions are based on.