Greenhouse Gasses






Sea-Level Rise













What Targets Should We Adopt? (page 30)

Germany’s Potsdam Institute has found that if we are to keep the rise in temperature below 2C, we can only burn 190 billion tonnes (Gt) of carbon between now and 2050, on top of the 500 billion tonnes we have already burnt. At the current rate of 8.5 Gt a year, we will hit the absolute limit in 22 years. Since we can’t stop suddenly, the world’s nations will need to organize and ration the decline, signing onto a 4-5% annual decrease in their carbon emissions.

Source: The Climate Interactive Scoreboard - an open-source world for climate simulations where you can try out various scenarios.

Earth’s Future Electricity (page 46)

A paper from Harvard that looked at the global wind energy potential found that a network of land-based 2.5 MW turbines restricted to non-forested, ice-free, non-urban areas operating at only 20% capacity (compared to 40% for most new turbines) could supply more than 40 times the world’s current use of electricity, and more than 5 times the world’s total use of energy. In the United States, specifically in the central plain states, wind could supply 16 times the current use of electricity.

Source: PNAS, April 2009

Nuclear - Hope or Hype? (page 56)

A Vermont Law School analysis found that nuclear electricity would cost 12-20 cents kwh, compared to 6 cents for renewable energy. Adding 100 new nuclear reactors would cost between $1.9 and $4.1 trillion more, over the reactors’ lifetime, compared to efficiency and renewables.

Source: Scientific American blog, June 2009

In Ontario, the only ‘compliant’ quote for two new nuclear power plants that the Ontario government received came in at three times the expected cost, and would have cost $26 billion, wiping out the province’s entire non-nuclear expansion budget for 20 years. Similarly, Turkey’s only bid came in at 21 cents kWh.

Source: Climate Progress, July 2009

Clean Coal - Hope or Hype? (page 60)

Harvard’s Belfer Center for Science and International Affairs has published a major study on the Realistic Cost of Carbon Capture, finding the likely cost of avoided carbon to be $150/tonne, and the resulting cost of “clean coal” electricity to be 20 cents kWh, compared to much lower prices for renewables and efficiency. The only way the cost could be reduced was if carbon capture was used for “enhanced oil recovery” in hard-to-extract oil wells - but this would produce as much new CO2 from the extracted oil as was buried, rendering the exercise pointless. 

Source: Climate Progress, 2009

A study from the University of Toronto’s Munk Centre for International Studies warned of dramatic unintended environmental consequences that could result from storing large quantities of CO2 in the Earth’s mantel, including water contamination and unexpected leakage. It noted that coal-plants using the CCS process would require 25-33% more water.

Source: New York Times, October 2009

Earth’s Future Farms (page 62)

In November 2009, the prestigious Worldwatch magazine published a striking critique of the seminal report Livestock’s Long Shadow, in which the authors conclude that the global warming impact of livestock is not 18% of GHGs by 51%. They make a lot of valid points, but two of their big ones are very questionable. To Livestock’s Long Shadows estimate of 7.5 Gt of annual GHGs they add 8.8 Gt for livestock respiration, which the IPCC discounts as invalid because all respiration is, by definition, carbon neutral. They also ask “what if all land used for livestock was growing forest instead?” and add 2.6 Gt of CO2, but this seems to assume that all grasslands would become forest, which is ecologically not true, and ignores the enormous potential of grasslands to store carbon if we change the way cattle graze (see Solution #43)

Source: Worldwatch Magazine, Nov 2009

Earth’s Future Atmosphere (page 66)

The Worldwatch Report Mitigating Climate Change Through Food and Land Use looks at the potential for reduced GHGs and carbon sequestration from land-use, involving farming, forestry and habitat protection. The IPCC’s estimates for changed farming methods suggest that between 1.5 and 4.3 Gt a year of CO2 could be sequestered each year by 2030, and that a changed approach to forestry could sequester 5.8 to 13.8 Gt. Together, these amount to 7.3 to 18.1 Gt, representing 20% to 50% of the total 2008 CO2 emissions of 36.6 Gt.

Source: Worldwatch Institute, 2009









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