Carbon removal is the process of removing carbon dioxide from the atmosphere and locking it away for decades, centuries, or millennia.

This could slow, limit, or even reverse climate change — but it is not a substitute for cutting greenhouse gas emissions. Carbon removal is sometimes referred to as carbon dioxide removal or CDR, and technologies for implementing carbon removal are sometimes called Negative Emissions Technologies (NETs).

At the Institute, we believe that scaling carbon removal responsibly will require more than demonstrating techno-economic feasibility. Instead, "responsible" scaling of carbon removal means addressing other aspects of what might make carbon removal approaches better or worse for society: what socio-environmental impacts might result? What co-benefits might be provided? Who gets to have a say in how, when, and where carbon removal happens? Who profits from it? Does it exacerbate ongoing emissions, or entrench existing inequalities?

 Current investment into carbon removal deployment is accelerating at an unprecedented pace; this presents many challenges, but also opportunities to create a paradigm shift in how large-scale projects are built and who has a seat at the table to ensure responsible deployment.

Prominent Methods for Carbon Removal:

• Afforestation/Reforestation- planting massive new forests 
• Soil Carbon Sequestration- using no-till agriculture and other practices to increase the amount of carbon stored in soils 
• Biochar- creating charcoal and burying it or plowing it into fields 
• Bioenergy with CCS or BECCS- capturing and sequestering carbon from biofuels and bioenergy plants 
• Enhanced Mineralization- spreading crushed rocks over land to absorb carbon dioxide from the air or exposing them to carbon dioxide-rich fluids 
• Direct Air Capture- building machines that would suck carbon dioxide directly out of the atmosphere and bury it 

Oceans-Based Methods

• Ocean Alkalinization- spreading alkaline materials, such as lime, over the ocean 
• Ocean Fertilization- fertilizing selected areas of the ocean by spreading nutrients, such as iron, over the surface 
• Artificial Upwelling- fertilizing selected areas of the ocean by pumping nutrient-rich waters from the depths to the surface 
• Artificial Downwelling- accelerating the transport of carbon to the ocean depths by pumping surface waters downward

Similar methods for capturing and storing other greenhouse gases, such as methane, are known as greenhouse gas removal.