That thick black line is the observed reality, plumetting below all the predictions. I've copy-pasted their executive summary below, but you should really just spare a few minutes and read the whole PDF here.
• Climate change impacts are happening at lower temperature increases and more quickly than projected.
• The Arctic's floating sea ice is headed towards rapid summer disintegration as early as 2013, a century ahead of the International Panel on Climate Change (IPCC) projections.
• The rapid loss of Arctic sea ice will speed up the disintegration of the Greenland ice sheet, and a rise in sea levels by even as much as 5 metres by the turn of this century is possible.
• The Antarctic ice shelf reacts far more sensitively to warming temperatures than previously believed.
• Long-term climate sensitivity (including "slow" feedbacks such as carbon cycle feedbacks which are starting to operate) may be double the IPCC standard.
• A doubling of climate sensitivity would mean we passed the widely accepted 2°C threshold of "dangerous anthropogenic interference" with the climate four decades ago, and would require us to find the means to engineer a rapid drawdown of current atmospheric greenhouse gas.
• Carbon dioxide (CO2) emissions are now growing more rapidly than "business-as-usual", the most pessimistic of the IPCC scenarios.
• Temperatures are now within ≈1°C of the maximum temperature of the past million years.
• We must choose targets and take actions that can actually solve the problem in a timely manner.
• The object of policy-relevant advice must be to avoid unacceptable outcomes and seemingly extreme or alarming possibilities, not to determine just the apparently most likely outcome.
• The 2°C warming cap is a political compromise; with the speed of change now in the climate system and the positive feedbacks that 2°C will trigger, it looms for perhaps billions of people and millions of species as a death sentence.
• To allow the reestablishment and long-term security of the Arctic summer sea ice it is likely to be necessary to bring global warming back to a level at or below 0.5°C (a long-term precautionary warming cap) and for the level of atmospheric greenhouse gases at equilibrium to be brought down to or below a long-term precautionary cap of 320 ppm CO2e.
• The IPCC suffers from a scientific reticence and in many key areas the IPCC process has been so deficient as to be an unreliable and dangerously misleading basis for policy-making.
1 comment:
I read through that one a couple days ago, and I think it's the type of message that needs to be pushed, but won't be (I'm extremely pessimistic on humanity's chances of accomplishing anything other than an eventual die off). I find it hard to explain to friends that things are much, much worse than they've been lead to believe, and it's possibly too late already. The "draw CO2 from the atmosphere" plan seems great, until you realize we have no idea how to do this (maybe grow massive ocean kelp farms, harvest it, and bury it every year?) on a large scale.
Worse, the IPCC report, with what I thought were clearly understatements of the problems and scale of the necessary solutions, isn't being acted upon by those that have the most to do (North America, Asia). Kyoto, which was, even at the time it was drafted, seen as a first step just to get started on larger actions, has targets that haven't been met by all but a few.
I'm thinking I may need to re-consider my love for living near the ocean. Although a houseboat would be pretty good.
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