The world has the potential to hold global warming below 2 degrees Celsius, a new report says, but only if there is a strong policy framework throughout the world and global commitment and action across all sectors.
McKinsey & Company released its report, "Pathways to a Low-Carbon Economy," in January, updating a report that was originally released two years ago. The report charts a pathway that relies on increased energy efficiency, a shift to a low-carbon energy supply, land use changes (growing forests and changing farming practices), and behavioral changes, such as traveling less or eating less meat. If those measures are pursued apace starting next year, the report finds that global greenhouse gas (GHG) emissions could be 35 to 40 percent below 1990 emission levels by 2030. That would result in GHGs peaking at 480 parts per million (ppm) in Earth's atmosphere, which is sufficient to keep warming below 2 degrees Celsius.
However, delaying action by even 10 years would make it difficult to hold GHG peak concentrations below 550 ppm, and doing so would be much more expensive.
The report notes that many GHG abatement methods actually have negative costs, although their capital costs may be quite high. For instance, most energy efficiency measures pay for themselves in saved energy costs, so their total cost to society is negative.
Other measures, such as carbon capture and storage for fossil-fueled power plants, are much more expensive. Rolling it all together, the total worldwide cost would equal less than 1 percent of the forecasted global economic activity in 2030. But that happens only if the most economically rational GHG abatement opportunities are pursued to the full potential, a possibility that the report acknowledges as clearly optimistic.