Carbon removal, or Carbon Dioxide Removal (CDR), refers to the process of actively capturing existing carbon dioxide (CO 2) directly from the atmosphere and storing it durably. This is essential for counteracting historical emissions and achieving net-zero goals, complementing efforts to reduce current emissions.
Carbon removal, often referred to as Carbon Dioxide Removal (CDR), encompasses a range of techniques designed to actively extract existing CO 2 from the ambient air. Unlike carbon capture technologies that trap emissions at their source (e.g., a power plant smokestack), carbon removal targets the vast reservoir of greenhouse gases already accumulated in the atmosphere. This makes it a critical strategy for addressing historical emissions and is considered vital by scientists, including the IPCC, for reaching net-zero targets and limiting global warming.
These technologies and practices are a key pillar of climate action, alongside drastically reducing ongoing emissions. For investors and businesses in the climate finance space, understanding the distinction is crucial. While investing in carbon markets like the EU ETS learn more about how the EU Carbon Market works drives emissions reduction, supporting carbon removal contributes to cleaning up what's already there.
How Carbon Removal Works: Key Approaches
Carbon removal methods can be broadly categorized into nature-based, technological, and hybrid solutions. Each approach captures CO 2 and aims to store it in a stable form for a long duration.
- Nature-based Solutions: These leverage natural processes.
- Afforestation & Reforestation: Planting new trees or restoring old forests, which absorb CO 2 through photosynthesis and store it in their biomass and the soil.
- Soil Carbon Sequestration: Using farming and land management practices (like no-till farming) to increase the amount of organic carbon stored in the soil.
- Technological Solutions: These involve engineered systems.
- Direct Air Capture (DAC): Large-scale facilities use chemical processes to filter CO 2 directly from the surrounding air. The captured CO 2 is then compressed and stored, often underground.
- Enhanced Mineralization: Crushing specific types of rocks that naturally react with CO 2 and spreading them on land or in the ocean to accelerate this natural carbon absorption process.
- Hybrid Solutions:
- Bioenergy with Carbon Capture and Storage (BECCS): Biomass (like trees or crops) absorbs CO 2 as it grows. It is then burned to generate energy, and the resulting CO 2 emissions are captured and permanently stored underground.
Concrete Examples
- Technological Case: A Direct Air Capture (DAC) facility in Iceland, operated by companies like Climeworks, uses giant fans to pull in ambient air. The CO 2 is filtered out, mixed with water, and injected deep underground where it reacts with basaltic rock and mineralizes, turning into solid stone for permanent storage.
- Nature-based Case: A large-scale mangrove restoration project in Southeast Asia. By replanting mangrove forests along coastlines, the project not only draws down significant amounts of atmospheric CO 2 (stored in the trees and soil) but also provides critical co-benefits like coastal protection and restored biodiversity.
For more in-depth scientific details, you can read the IPCC's assessment on Carbon Dioxide Removal.