Monday, 1 November 2010

Planetary Desolation

… please remember what the nation’s top climate scientist has said:

… the most serious effects will be visited upon the young and the unborn, the generations that bear no responsibility for the problem.

The most important effects, I believe, will be those that are irreversible for all practical purposes, specifically (1) extermination of species, and (2) ice sheet disintegration and sea level rise. If we continue business-as-usual energy policy, using more and more fossil fuels, it is likely that we will have:  (1) rapid climate change that will combine with other pressures on species to cause the rate of extinction of plants and animals to increase markedly, leading in some cases to ecosystem collapse, snowballing extinctions, and a more desolate planet for future generations.  (2) meter-scale sea level rise this century, and ice sheets in a state of disintegration that guarantees future sea level rise in the 10-meter-scale, with a continual reworking of future global coastlines out of humanity’s control.
I would add that the planetary desolation our continued inaction would leave our children includes the loss of the inland glaciers that provide fresh water for a billion people, irreversible ocean acidification and Dust-Bowlification across much of the habited land mass (see “Hell and High Water “).
Back when I wrote my 2006 book, it took a lot of effort interviewing top climate scientists and finding relevant studies to figure out what will happen in the world of tripled or quadrupled CO2 concentrations (from preindustrial levels) we are heading toward on our current emissions path.  Scientists hadn’t been doing a lot of analysis of those ’scary’ scenarios because they had assumedHomo ’sapiens’ sapiens would not be so stupid as to ignore their science-based warnings.
Now that the scientific community knows better, we’re seeing more and more studies of the impact of a tripling (825 ppm) or quadrupling (1100 ppm) — which is not to say that a doubling (to 550 ppm) wouldn’t be catastrophic:
It’s just that a tripling or quadrupling leads to impacts that are as far beyond catastrophic as those catastrophic impacts are beyond our current climate.  Here’s just a few analyses from the last two years:
And that isn’t the worst case.  No, the worst case is that the temperature rise occurs in 50 years, not 90 — and that the impacts last for centuries:
This is the “plausible worst case scenario” for 2060 from the UK Met Office that occurs in 10% of model runs of high emissions with the carbon cycle feedbacks [temperature in degrees Celsius, multiple by 1.8 for Fahrenheit]:
Graphic of chnage in temperature
Of course, the above temperature plot is just for a mean global warming 5.4°C (9.7°F), which is business as usual for 2100 according to many analyses (see M.I.T. doubles its 2095 warming projection to 10°F — with 866 ppm and Arctic warming of 20° F).
But what’s really scary is that:
  1. All of those beyond catastrophic impacts would be happening simultaneously, making it all but impossible to imagine that the devastated rich countries would be able to offer much assistance to the beyond-devastated poorer countries.
  2. We’re doing this to our children in spite of being warned (see Is the global economy a Ponzi scheme?) — in spite of being told by virtually every major economic analysis that it could be avoided at a net cost of 1/10 of a penny on the dollar, not counting all of the ancillary benefits (improved public health, sharp drop in money flowing overseas to buy oil).

Post  from climate progress