Threshold for dangerous climate change closer than believed?

[Readers interested in this subject should also see the TED talk about the West Antarctica Ice Shelf (WAIS). The WAIS sits on ground that is below sea level and so if the warming seas get underneath the ice sheet it could break up very fast. New evidence indicates this could start to happen if the planet warms up more than 1C. We have already warmed up the planet .8C Must view: Scary stuff- Discovering ancient climates in oceans and ice - http://bit.ly/96Fnyz

The fact that ICT now accounts for almost 42% of energy consumption in US homes and projections by the IEA that ICT could consume 40% of the world’s electricity by 2030 means we in the ICT industry have to do something before we become the new climate villains. This is unsustainable and needs to be stopped. ICT is the one industry that has the “smarts” and is used to moving at Internet speeds with easy access to VC money. We need to act now.


--BSA]


http://www.cejournal.net/?p=4054

Threshold for dangerous climate change closer than believed?
Recent research suggests current target for limiting global warming is actually unsafe

The overarching goal for international climate policy is to limit global warming to no more than 2 degrees C over pre-industrial levels. Beyond that threshold, climate scientists have believed, lies dangerous climate change, including sea level rise that could inundate major cities.
But a study published in the September issue of the Journal of Quaternary Science suggests that the threshold may be lower than 2° C. (Click for a press release on the research.)
“The results here are quite startling and, importantly, they suggest sea levels will rise significantly higher than anticipated and that stabilizing global average temperatures at 2˚C above pre-industrial levels may not be considered a ’safe’ target as envisaged by the European Union and others,” says study co-author Chris Turney of the University of Exeter in the U.K. (quoted in a press release).
This isn’t the first suggestion that targets for preventing dangerous climate change have been set too high. Based on research into ancient climates, James Hansen, head of NASA’s Goddard Institute for Space Studies, and a group of colleagues, have made a similar argument:
If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm, but likely less than that.
Current emissions targets are supposed to help achieve the goal spelled out in the United Nations Framework Convention on Climate Change, signed by 192 nations in 1992: avoid “dangerous interference with the climate system.” But what exactly is the threshold of danger?
As I wrote in a post back on December 17th, 2009, the IPCC’s Fourth Assessment Report, published in 2007, concluded with high confidence that an increase in the global mean temperature of more than 2 degrees C above the long-term average would lead to widespread losses in biodiversity, declining productivity of agriculture globally, and a “commitment” to widespread de-glaciation of Greenland’s ice sheets (and thus a significant rise in sea level). With medium confidence, the report concluded that such a temperature increase would lead to de-glaciation of West Antarctica’s ice sheets as well.
Based on this, 16 developed and developing nations that account for about 80 percent of the world’s greenhouse gas emissions agreed at the 2009 G8 Summit, in July 2009 that an increase in the global mean temperature of more than 2 degrees C above the long-term average would put the world at substantial risk of dangerous climate change.
To avoid that unhappy outcome, climate policy makers have been trying to forge an agreement to keep CO2 concentrations from rising above 450 parts per million, which is considered necessary for limiting global warming to no more than 2 degrees C.
Like James Hansen and his colleagues, Turney believes his new research shows this won’t be nearly good enough.
He and his co-author analyzed a set of global data on climatic conditions during the last interglacial period, which lasted from approximately 130,000 to 116,000 years ago. Like the current geologic period, the last interglacial was marked by relatively warm conditions and a retreat of glaciers and ice sheets. The analysis suggests that at that time, global temperatures were about 1.9°C higher than pre-industrial levels.
Most significantly, with temperatures just a little shy of 2°C higher than pre-industrial times, sea level was 6.6 meters to 9.4 meters higher than it is today, and it rose at double the rate being observed now. A sea level rise of that degree would swamp many coastal cities, affecting many tens of millions of people.
“The inevitable conclusion is emission targets will have to be lowered further still,” Turney concludes.

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