There is a curious appeal about round numbers - think the year 2000 end of the world cults that slowly came down from their mountain hideouts a few months later.
'100 months' to stop overheating [Guardian]
Rising greenhouse gas emissions could pass a critical tipping point and trigger runaway global warming within the next 100 months, according to a report today.
The estimate from the New Economics Foundation is based on when emissions will reach such high levels that it "is no longer likely" the world will be able to avoid a 2C rise in average temperatures. "We know climate change is a huge problem, but there's a missing ingredient of urgency," said Andrew Simms, policy director at the foundation.
I am sure that I can confidently predict that the planet will not avoid passing through the 450ppm level of emissions. Given the time taken for the current trade negotiations it will take 100 months just to get some sort of compromised, half baked climate change agreement.
Perhaps the 4 billion that are predicted to suffer severe water shortages and the ensuing migration and inevitable armed conflicts will speed things up. This article also gives me a chance to write about "potentially catastrophic" events.
Andrew Simms (one of the authors) discusses in more detail also in the Guardian. This is an article worth reading in full.
The final countdown [Guardian]
The concentration of carbon dioxide (CO2) in the atmosphere today, the most prevalent greenhouse gas, is the highest it has been for the past 650,000 years. In the space of just 250 years, as a result of the coal-fired Industrial Revolution, and changes to land use such as the growth of cities and the felling of forests, we have released, cumulatively, more than 1,800bn tonnes of CO2 into the atmosphere. Currently, approximately 1,000 tonnes of CO2 are released into the Earth's atmosphere every second, due to human activity. Greenhouse gases trap incoming solar radiation, warming the atmosphere. When these gases accumulate beyond a certain level - often termed a "tipping point" - global warming will accelerate, potentially beyond control.
All this is well known (or should be to G&E readers) as are the feedback mechanisms but Simms' description is a good one:
Because of such self-reinforcing positive feedbacks (which, because of the accidental humour of science, we must remind ourselves are, in fact, negative), once a critical greenhouse concentration threshold is passed, global warming will continue even if we stop releasing additional greenhouse gases into the atmosphere. If that happens, the Earth's climate will shift into another, more volatile state, with different ocean circulation, wind and rainfall patterns. The implications of which, according to a growing litany of research, are potentially catastrophic for life on Earth. Such a change in the state of the climate system is often referred to as irreversible climate change.
The other paragraph that caught my eye concerns those forward looking Cubans.
In terms of what is possible in times of economic stress and isolation, Cuba provides an even more embarrassing example to show up our national tardiness. In a single year in 2006 Cuba rolled-out a nationwide scheme replacing inefficient incandescent lightbulbs with low-energy alternatives. Prior to that, at the end of the cold war, after losing access to cheap Soviet oil, it switched over to growing most of its food for domestic consumption on small scale, often urban plots, using mostly low-fossil-fuel organic techniques. Half the food consumed in the capital, Havana, was grown in the city's own gardens. Cuba echoed and surpassed what America achieved in its push for "Victory Gardening" during the second world war. Back then, led by Eleanor Roosevelt, between 30-40% of vegetables for domestic consumption were produced by the Victory Gardening movement.
Time to go and harvest some runner beans and potatoes from my back garden.