The planet needs to go on a carbon diet. Our current catastrophes—devastating wildfires, stronger hurricanes, and rising seas—are consistent with the warnings scientists made in the 1980s and 1990s. Past burning of fossil fuels, including oil, coal, and natural gas, has released greenhouse gases into the atmosphere and caused the earth to warm by 2° Fahrenheit (a bit more than 1° Celsius) since the pre-industrial era (1880-1900).
In 2015, the Paris Climate Agreement set goals for countries to try and limit the increase in global warming to well below 2.0°C (3.6°F) above pre-industrial levels to avoid worsening impacts of climate change, and pursue efforts to limit the temperature increase to below 1.5°C (2.7°F). According to the Intergovernmental Panel on Climate Change (IPCC), in order to reach these targets, global greenhouse gas emissions need to be cut in half by 2030, and reach “net zero” by mid-century for the 1.5°C degree target. This not only requires drastically cutting our greenhouse gas emissions fast, but removing CO2 from the atmosphere. The term “net zero” simply means that any greenhouse gas emissions released are balanced by an equal amount being taken out of the atmosphere.
Scientists, engineers, and other researchers are exploring pathways and models to figure out what needs to happen over the next few decades to get the U.S. to net zero. The Net-Zero America Project (NZAP), being released in December 2020, models several technology pathways to reach net-zero GHG emissions by mid-century. Another initiative, the Zero Carbon Action Plan (ZCAP), released in October 2020, looks at decarbonizing six key economic sectors. And there are other net-zero plans and carbon management solutions, including reports from the Center for Energy and Climate Solutions.
While their modeling and projections may incorporate different inputs and show different outcomes, all these projects highlight the same core areas of our economy that need to undergo major transformation in order to get to net zero:
- Creating carbon-free electricity
- Electrifying transportation
- Adopting energy efficiency measures and electrifying our buildings
- Decarbonizing industry and manufacturing
- Transforming our farming and food habits
Most pathways to keeping global temperatures in check—and every pathway to stopping at 1.5 degrees—incorporates absorbing carbon emissions from the atmosphere. Carbon dioxide is the only greenhouse gas that can be taken out of the atmosphere and stored; doing it at a scale large enough to make a difference is a challenge.