Rewetting dried wetlands could stop 100 billion tons of CO2 emissions
Dried-out wetlands, such as peatlands, hold vast reserves of carbon that have been locked away for thousands of years. When these areas are drained, the stored carbon is exposed to oxygen, causing the organic matter to decompose and release carbon dioxide into the atmosphere. Scientists estimate that up to 100 billion tons of carbon dioxide could be released from degraded wetlands if no action is taken, a volume comparable to several years of global fossil fuel emissions.
Rewetting these wetlands is emerging as a highly effective yet often overlooked strategy for mitigating climate change. By restoring water levels, the decomposition process is slowed or halted, effectively trapping carbon in the soil and preventing it from entering the atmosphere. This approach offers a direct way to reduce greenhouse gas emissions while also restoring the ecological health of these environments.
Healthy wetlands act as natural carbon sinks, storing more carbon per square meter than most other ecosystems. They have accumulated these reserves over millennia, and their waterlogged conditions prevent organic material from breaking down. Once drained, however, the system changes dramatically. The introduction of oxygen accelerates the breakdown of plant matter, releasing carbon at a rapid pace. This process transforms wetlands from carbon reservoirs into significant sources of emissions.
Rewetting is a relatively simple but powerful intervention. By raising the water table back to natural levels, the conditions that preserve carbon are restored. The benefits extend far beyond climate action. Restored wetlands quickly become vibrant ecosystems, providing habitat for plants, amphibians, birds, and insects. They play a crucial role in water purification by filtering out pollutants, and they also help manage water flow, absorbing excess rainfall to reduce flooding and slowly releasing stored water during droughts.
In addition to supporting biodiversity and improving water quality, rewetted wetlands can increase climate resilience for surrounding communities. Their natural sponge-like capacity helps buffer extreme weather events, which are becoming more frequent due to climate change. These benefits make wetland restoration a multi-faceted solution, addressing both environmental and societal challenges.
Several countries have begun to recognize the value of this approach. In parts of Europe, large-scale rewetting projects are underway, converting former agricultural peatlands back into functioning wetlands. These initiatives are supported by both environmental policy and funding mechanisms aimed at reducing emissions while safeguarding biodiversity.
However, challenges remain. Restoring wetlands requires significant upfront investment, as well as long-term management to ensure they stay protected. In some regions, land use conflicts can slow progress, particularly where drained wetlands have been converted into farmland or other agricultural uses. This can create tension between conservation goals and local economic interests.
Additionally, restoring the delicate hydrology of wetlands is complex, often requiring specialized knowledge and careful monitoring to avoid unintended consequences, such as flooding or changes to surrounding ecosystems. Climate variability and changing weather patterns can further complicate restoration efforts, making adaptive management essential. International cooperation, strong policy frameworks, and sustained funding will be necessary for scaling up these efforts to the levels needed for meaningful climate impact.
Rewetting dried wetlands represents a rare opportunity in climate policy: a single action that can deliver immediate carbon savings while also revitalizing ecosystems and strengthening resilience to climate impacts. As the urgency to reduce global emissions intensifies, strategies like this, rooted in nature and backed by science, will be critical in shaping a sustainable future.
By prioritizing wetland restoration alongside other climate measures, governments and organizations can protect one of the planet’s most effective natural carbon storage systems. The potential to prevent the release of 100 billion tons of carbon dioxide makes this an intervention of global significance, with benefits that extend far beyond carbon accounting. Restoring wetlands is not only a matter of climate mitigation, it is an investment in the health and stability of the planet’s life-support systems.
