A Summary of Conclusions from “Six Degrees – Our Life on a Hotter Planet” by Mark Lynas
Book Cover
In his book Mark refers to a vast library of scientific reports and studies in order to outline the effects on the planet of climate change equivalent to global temperature rises of one, two, three, four, five and six degrees. Colin Carritt of Sustainable Woodstock has summarised the conclusions for each degree rise and has kindly given permission for us to publish the summaries on the CNL website. This article covers the one and two degree rise situations.
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One Degree
Return of the “Mid-west American dust bowl” but with greater vengeance.
Africa’s three highest peaks will have lost half their glacial area compared to 1987. This will affect downstream water supply, wildlife and bio-diversity.
The Arctic “tipping point” is coming. Already:-
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world temp has risen 0.7°C over past 10 years
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we have lost permafrost that has led to the draining of 10,000 lakes worldwide
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each year an extra 10,000 sq km of ocean is created from melting artic ice sheet
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in Sept 2005 an area of the arctic ice sheet the size of Alaska vanished.
Snow and ice reflect 80% of sun’s heat whereas the dark ocean absorbs 90% of the sun’s heat.
Rock-falls will be widespread in alpine regions due to loss of alpine permafrost
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which will have implications for population settlements in those regions.
Coral reefs are already in serious danger. Some 70% of reefs world-wide are dead or dying.
The increase in hurricane activity is due to warmer oceans
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in 2004 the first ever hurricane in Brazil in the southern hemisphere, a certain sign of climate disturbance
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hurricane Vince landed in Huelve, Spain, the first tropical cyclone ever recorded in Europe.
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hurricanes in 2005 (Katrina, Wilma, Rita, etc.) killed 1000 people left 1,000,000 homeless and caused $200 billion damage
The lives of ¼ million people on tropical attols are threatened eg Tuvalu (probably lost already), Kribati, Marshall Islands, Tokelau and the Maldives.
Two Degrees
By now, the release of greenhouse gases are beginning to alter the oceans. Just two degrees of global warmimg may render some parts of the southern oceans toxic to CaCO3 and thus to one of life’s essential building blocks, plankton.
Heatwaves.
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in Europe in 2003 35,000 people died prematurely due to heat related illnesses
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crop losses were $12 billion
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forest fires cost $1.5 billion
With 2° warming, summers like 2003 will occur almost every other summer.
Wildfires may penetrate as far north as the Baltic coast
Glacial melt rates will double. One particular Greenland glacier has already thinned by 15 metres every year since 1995 and the flow rate has doubled.
If the entire Greenland ice sheet were to melt (possible with 2° though it would take perhaps 140 years) then Miami, Manhattan, London, Bombay, Bangkok, and Shanghai, to name but a few, would be inundated.
The disappearance of mountain glaciers and snow-pack will create water shortages
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in the Indian sub-continent, Peru, Ecuador and Bolivia
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by 2050 the Andes glaciers will have shrunk by 40% – 60%
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crippling droughts can be anticipated in Los Angeles and California.
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From Nebraska to Texas the anticipated drought would be many times worse than the 1930s “dust bowl” phenomenon.
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polar bears would probably rapidly become extinct.
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the tundra would disappear releasing massive volumes of methane (a major greenhouse gas)
The Mediterranean countries will become drier and hotter with significant water shortages.
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sea level rise may affect the homes of millions around the world as the sea invades low lying cities
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IPCC estimate sea level rise of 18 to 59 cm – many say the figure will be more
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monsoons would increase in India and Bangladesh leading to mass migration of its populations.
Crop Production.
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some areas would benefit – Indiana, Illinois, Ohio, Michigan, Wisconsin – where yields might double. Canada will be a net beneficiary.
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citrus growers in Miami may benefit provided they are not hit by hurricanes.
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in the UK sweet corn, soft fruits and vegetables may benefit.
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but maize, a staple for so many will suffer particularly in Central and South America
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most of Africa will suffer loss of production
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US soya bean production will be cut by 50%
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international food price stability will have to be agreed to prevent widespread starvation.
· “Nature 2004” estimate that more than a third of all species will suffer potential extinction at 2° C rise
Readers:
You should be aware that if the climate change world summit in Copenhagen in December 2009 cannot agree to act to limit the rise to two degrees, the science suggests that changes may escalate out of control.
The predictions for three and four degrees will be published next month.
Geoff Feasey
16th September 2009
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