The Azimuth Project
Stabilization wedges (Rev #1)

Contents

Idea

Stephen Pacala and Robert Socolow have sketched a flexible plan for tackling the global warming problem:

They list 15 measures, each of which could reduce carbon emissions by 1 billion tons per year by 2057. They believe global warming would be manageable, though still a serious problem, if 12 of these measures were carried out by that time. They call these measures stabilization wedges, thanks to their appearance in a chart that illustrates their effects.

Details

Here are the 15 stabilization wedges:

wedge

Here’s a summary of what Pacala and Socolow claim:

  • If we adopt 12 of these measures, we could lower our carbon emissions from the current figure of 8 billion tons per year to 4 billion tons per year by 2057. This might mean 450 parts per million of CO2 in the atmosphere by this time, and a global temperature rise of 2 °C. With this, we could still expect coastal flooding that affects millions of people per year. Cereal crop yields will tend to decrease in low latitudes. And up to 30% of species might face the risk of extinction, with most coral reefs being bleached. But this is the “good” scenario.

  • If adopt only 8 of the measures, we could hold our carbon emissions constant at the current figure of 8 billion tons per year. This might mean 525 ppm of CO2 in the atmosphere, and a global temperature rise of 3 °C. With this, we can expect the widespread death of coral reefs. We can also expect the bad consequences listed above, and: 30% of coastal wetlands being lost, with most ecosystems becoming carbon sources as permafrost thaws and vegetation burns or rots.

  • If we adopt none of the measures, we can expect carbon emissions to double by 2057, to 16 billion tons per year. This might mean 800 ppm of CO2 in the atmosphere, and a global temperature rise of 5 °C. With this, we can expect that more than 40% of species will face extinction. We can also expect the bad consequences listed above, and cereal crop yields decreasing in some mid- to high-latitude regions.

category: action