For addressing the climate impact of cars, balancing out their tailpipe CO2 emissions by speeding up the rate at which CO2 is removed from the atmosphere in other locations is a strategy that is just as essential as any other option. The importance of this insight is not widely appreciated (at least not yet, when this page was first written). Moreover, it applies to much more than cars. Balancing CO2 emissions is even more crucial for other energy-intensive forms of transportation, notably trucks and aircraft.

The need to balance the carbon cycle is fundamental for climate mitigation. Thinking "Beyond Carbon Neutral" in order to develop ecologically and economically sound ways to pull more CO2 out of the air is a crucial complement to the more widely known options for cutting CO2 and other greenhouse gas (GHG) emissions through energy efficiency and non-carbon sources of energy such as solar, wind and nuclear.

Although Carbon Dioxide Removal (CDR, as it's often termed) can counterbalance the CO2 emitted from any source, including power plants and factories, it has a special role in addressing the Liquid Carbon Challenge. This challenge refers to the fact that liquid hydrocarbon fuels are by far the most convenient energy carriers for the vast majority of transportation applications and that it is not practical to capture CO2 from tailpipes or jet exhausts. Liquid hydrocarbons are the largest source of energy for the global economy and likely to remain so for at least two decades or longer. 

Posts linked to this page will provide basic background on the global carbon cycle and discuss CDR options as a way to help orient individuals who have mainly looked at climate mitigation in terms of energy technologies and policies for reducing emissions.


In a commentary published in the Proceedings of the National Academy of Sciences, Bill Schlesinger and I argue that now and for the foreseeable future, it is far better to pursue natural climate solutions that counterbalance fossil fuel CO2 emissions than it is to pursue most forms of bioenergy. The short summary of our article on "Reconsidering Bioenergy" given here includes a link to the PNAS piece itself. 


Understanding what it takes to balance CO2 emissions is critical for unraveling the long-running debates about the role of biofuels for climate protection. Many people assume that the CO2 emitted from biofuel combustion is automatically balanced by CO2 uptake during biofuel crop growth. However, such an assumption is rarely valid and is in fact far from the truth for biofuels as they are actually produced today. See the post "When do biofuels really balance carbon?" for an explanation.

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