Climate change policy is aimed at taking concerted action, at the international and national levels, that will give us the best chance of avoiding “dangerous” levels of climate change. This breaks down into several steps:
The near-universal consensus of policy makers is an average global temperature rise of more than two degrees centigrade (3.6 F) would be dangerous. Above this level, feedback mechanisms such as accelerated melting of the icecaps and massive release of methane from melting Siberian permafrost will probably kick in, sending global warming spiraling out of control. What would One-Six degrees of average warming mean?
Setting a Target:
Next we need to set a target for stabilizing CO2 concentrations in the atmosphere that will give us all a good chance of staying within two degrees of warming. (The current level is 383 parts per million, up from 280 ppm before the industrial revolution, and currently rising at over 2 ppm per year.)
There is uncertainty about the climate’s sensitivity to CO2 levels and therefore about the right target to set. Most scientists estimate that it should be a maximum of 400-450 ppm (lower than the 550 ppm that most governments are currently talking about as being politically feasible.) Here’s a helpful discussion of target levels,
This is the hard part. Governments need to agree on binding carbon emission reduction targets that will enable us to keep atmospheric concentrations of CO2 within safe limits.
The Kyoto Protocol signed in 1997 and ratified in 2004 was the first step in this direction. However, the biggest polluters, USA and China didn’t sign up to Kyoto, the target (5.2 % emissions reductions below 1990 levels by 2012) are smaller than many analysts believe are necessary, and some of the countries that did sign up are set to overrun their targets.
The recent Bali meeting was the opening to negotiations for an international agreement to replace Kyoto when it runs out in 2012.
Either system aims to more accurately reflect the social cost of emitting carbon, and to shift the incentives for consumers, businesses and governments away from emitting greenhouse gases and towards clean energy choices. Some of the necessary government policies that would then be economically attractive are to:
- Massively improve the energy efficiency requirements for homes, commercial buildings and new construction.
- Substantially reduce energy loss in power generation.
- Develop and implement technology to capture the CO2 produced by coal power plants and store it underground.
- Substantially increase the proportion of our power that comes from renewable sources, e.g. wind, waves and solar.
- Double or triple the average fuel economy of our cars and trucks.
- Introduce hybrid vehicle technology on a wide scale.
- Invest in improving public transport systems.
Global Justice: what’s holding things up?
The big stumbling block in international negotiations is allocating carbon emission cuts fairly between rich and poor nations. The developed nations, particularly the USA, argue that the developing nations (particularly China and India) which are set to become major greenhouse gas emitters should bear their fair share of emissions targets.
The developing nations respond that the USA and Europe caused most of the climate mess we’re in, and got rich in the process; now the poor countries ought to have a shot at economic development while the rich countries deal with climate change.
Ecoequity does a good job of laying out the issues and proposes a convincing solution with their “greenhouse development rights,” model.