Last month, I summarized the greenhouse gas emissions that are driving global warming. The good news is that a wide variety of solutions are available to either reduce those emissions or to actually remove carbon dioxide from the atmosphere and store it for centuries. The capacity of these solutions is sufficient to reduce net emissions to zero.

The book Drawdown by Paul Hawken and the website describe 82 different climate solutions. Estimates of the potential magnitude and cost of a similar set of solutions by the Intergovernmental Panel on Climate Change are illustrated in the figure below.

Emissions mitigation options and their costs (Figure TS.23, IPCC)

Emissions can be reduced by generating electricity using a variety of carbon-free technologies (wind, solar, hydro, nuclear, geothermal, tidal); by electrifying transportation and supporting walking, bicycling and public transit; by electrifying heating of buildings and homes; by using electricity or hydrogen to produce high heat in industrial processes; by replacing HFC refrigerants with gases that trap much less radiant heat; by adopting a plant-based diet and reducing food waste; and (not included in the IPCC assessment) by educating girls and providing family planning support.

Carbon removal from the atmosphere can be supported by protecting and planting forests, adopting farming practices that add carbon to soil, and by converting solid waste to biochar and adding it to soil.

It is clear from this figure that no one solution dominates when it comes to mitigation. Many are required to cut emissions in half.

Some of these solutions can already pay for themselves because they save or produce energy for less than the cost of energy from fossil fuels. Most solutions cost more than what we use currently, but for half of the potential mitigation, the cost is less than $20 per metric ton of CO2, which is equivalent to twenty cents per gallon of gasoline.

While these solutions are available, they aren’t truly solutions unless they’re rapidly implemented. Next month I’ll describe policies that will accelerate the execution of many of the possible solutions to the climate crisis.


  2. Climate Change 2022: Mitigation of Climate Change. Intergovernmental Panel on Climate.

Climate scientist Steve Ghan leads the Tri-Cities Chapter of Citizens Climate Lobby. Twitter: @citizensclimate