Today sees publication of the policymakers' summary for the third working group of the IPCC, the international organization that is attempting to deal with the global climate change crisis. Last month we reported on the publication of Working Group II's summary on "Impacts, Adaptation and Vulnerability," and now it's Working Group III's turn with "Mitigation of Climate Change."

Where the last report involved describing what effect anthropogenic climate change was having on the planet, this newest part of the Fourth Assessment Report concerns itself with looking at the costs and benefits that will be associated with minimizing the extent of the damage to the planet's climate and adapting to the changes already underway.

The message from Working Group III is an optimistic one. Utilizing four different scenarios for the future, it lays out two different categories of management strategies. Bottom-up strategies involve the use of technology and practices that are sector-specific: cleaner engine technology in cars, switching from fossil fuel power stations to nuclear and other non-carbon energy sources, increasing industrial efficiency, and so on. Top-down strategies are macroeconomic in scale and assume a concerted global effort to use markets to reduce greenhouse gas (GHG) levels.

Both bottom-up and top-down models find that there is economic benefit to mitigating CO2 and other GHG emissions, which have risen by 70 percent since 1970 and could almost double within the next 25 years if we carry on as usual.

Essentially, the message is similar to the Stern Review, but on a global scale: the price of inaction is going to be far higher than tackling global climate change.