November 2008

The key test of whether Obama is serious about reducing climate change will be the US position in international climate change negotiations leading up to the Copenhagen meeting in December 2009.

The Garnaut Climate Change Review did some modeling of 2020 and 2050 allocations for different countries based on a contraction and convergence approach to international emissions allocations, including for the US and Australia. There are two key factors associated with contraction and convergence, the contraction rate (which will determine the eventual stabilisation target) and the convergence date (which has very important equity issues). There is a much better change of a good comprehensive international agreement if the US would be willing to accept C&C, and accept a high contraction rate and an early convergence date.

The convergence date is the date at which all countries are allocated the same amount of per-capita emissions. A late convergence date, such as 2050, rewards high per-capita emitters by giving them more emissions allocations. Earlier convergence dates mean that high per-capita emitters, such as the US and Australia, will have deeper reductions in their 2020 allocations — if these countries pollute more than their allocation, they will have to purchase emission allocations from other countries. The Obama-Biden campaign’s climate policy is as follows:

Reduce Carbon Emissions 80 Percent by 2050: Barack Obama and Joe Biden support implementation of a market-based cap-and-trade system to reduce carbon emissions by the amount scientists say is necessary: 80 percent below 1990 levels by 2050. They will start reducing emissions immediately in his administration by establishing strong annual reduction targets, and they will also implement a mandate of reducing emissions to 1990 levels by 2020.

These figures are consistent with a stabilisation target of 550 ppm if the convergence date was 2050. According to Stern (p 195), a 550 ppm stabilisation target is 99% likely to lead to over 2 degrees C of warming, 69% likely to lead to over 3 degrees of warming, 53% likely to lead to over 4 degrees of warming, and 41% likely to lead to over 5 degrees of warming. This would have an unacceptably high likelihood of catastrophic impacts on civilisation and the planet.

In short, Obama’s policies are not as bad as the Australian policy of a 60% reduction by 2050, but are still not appropriate. They have an unacceptably high risk of catastrophic climate impacts, and shift too much of the job of reducing emissions away from the US.

Unfortunately, the Garnaut Review only modeled a convergence date of 2050, but the Global Commons Institute has tools available for modeling other convergence dates. For stabilisation at 450 ppm and a convergence date of 2050, Garnaut suggested that the US would have to have an allocation in 2020 of approximately 28% less than 2000 levels. Greenhouse gas levels will depend on carbon cycle feedbacks, worse feedbacks would require more reductions in allocations. A stabilisation target of 350 ppm would be much safer than 450 ppm.

Obama has got some policies right, such as 100% auctioning of emission permits, deployment of renewable energy, better energy efficiency, better electricity grid infrastructure, and weatherizing low-income households.


NASA climate scientist Dr James Hansen has made some comments on the US presidential election and on Australian climate change policy.

Hansen describes why he is cautious about whether the winning candidate in the US presidential election will actually deliver on climate change and states:

My caution about what a winning candidate will actually deliver is based on experience. If my “Trip Report” (, recounting dismal failure to help officials in various countries “get it”, did not convince you, I offer another example: Australia. Response to my “Dear Prime Minister Rudd” is at ( hardly illuminates the Australian position, but their subsequently stated goals of 450-550 ppm CO2 does. That plan appears to have been written by the coal industry, and, if adopted globally, practically guarantees destruction of most life on the planet. I would be more critical, except that much of the problem is probably due to our failure to make the climate story clear enough. More later on this topic and the ways in which moneyed interests finagle “cap and trade” to everybody else’s detriment.