The atmosphere accumulates carbon when we add more than natural systems can absorb. Carbon sequestration runs that process in reverse: it captures carbon dioxide from the air and stores it somewhere it won’t warm the planet.
Sequestration is not a silver bullet for the climate crisis. The scale of what we need to remove is enormous, and most sequestration methods face real limits in how much they can store, how permanently they can store it, and at what cost. But sequestration is a necessary part of the climate response, and understanding how it works matters for evaluating any climate solution that claims to use it.
Natural carbon sequestration
The largest carbon sinks on Earth are natural ones, and they’ve been sequestering carbon for millions of years.
Forests absorb CO2 through photosynthesis and store it in wood, roots, and soil. Tropical forests are among the most carbon-dense ecosystems on Earth. When forests are cleared or burned, that stored carbon is released back into the atmosphere, which is why deforestation is one of the largest sources of greenhouse gas emissions globally. Projects like TIST in Kenya and Uganda fund smallholder farmers to plant and care for trees, generating verified carbon credits in the process.
Soils hold more carbon than all the world’s vegetation and atmosphere combined. Healthy soils, particularly those managed with low-till or regenerative agricultural practices, can sequester significant amounts of carbon over time. Degraded soils release it. Our Fertile Ground project in India is built on exactly this principle: improving soil carbon while improving crop yields and farmer incomes at the same time.
Oceans absorb roughly a quarter of global CO2 emissions each year. Marine plants like phytoplankton and seagrass photosynthesize like land plants, pulling carbon out of the water column and, when they die, sinking it to the ocean floor. The Sundarbans mangrove forest is one of the most powerful examples: mangroves sequester carbon at rates far above terrestrial forests, while protecting coastlines from storm surge.
Peatlands are among the most powerful natural carbon stores on Earth. Though they cover only about three percent of the land surface, peatlands hold twice as much carbon as all the world’s forests combined. Protecting them from drainage and burning is one of the highest-leverage climate actions available.
Technological carbon sequestration
Natural sequestration has limits. Technological approaches aim to supplement it, though most are still in early stages of deployment at climate-relevant scale.
Direct Air Capture (DAC) uses industrial machines to pull CO2 directly from the atmosphere and store it underground in geological formations. The technology works, but it’s currently expensive, at hundreds of dollars per tonne, and energy-intensive. Several companies are building commercial DAC plants, and costs are expected to fall as the technology scales.
Bioenergy with Carbon Capture and Storage (BECCS) combines biomass energy production with carbon capture. Plants absorb CO2 as they grow; if the energy from burning them is captured and stored underground, the result is net carbon removal. BECCS faces land-use constraints and questions about its full lifecycle emissions.
Mineralization accelerates the natural process by which rocks absorb CO2. Enhanced weathering spreads crushed silicate rock on agricultural fields, where it reacts with CO2 in rain and soil to form stable carbonate minerals. It also improves soil fertility, making it a potentially high co-benefit approach.
How carbon sequestration connects to carbon credits
Many carbon credit projects are built on sequestration: they protect forests that would otherwise be cleared, restore degraded peatlands, fund regenerative agriculture, or plant trees on degraded land. When done with rigorous methodology and independent verification, these projects represent real, measurable removals of carbon from the atmosphere or real prevention of carbon release.
The key word is verification. Sequestration claims are only as credible as the methodology behind them and the auditors who check the numbers. That’s why Cool Effect only lists projects verified under recognized international standards, with third-party audit reports available for every project on the platform. You can read about how we vet every project we list, and browse the full portfolio below.
Whether you want to offset your travel, make a business climate commitment, or simply donate to a verified project, every credit on our platform is backed by a sequestration or emission reduction methodology that has been independently audited.