A recent study led by the University of Münster suggests that rewetting drained peatlands could help reduce carbon dioxide (CO₂) emissions, especially as global temperatures rise. Peatlands are natural reservoirs of carbon, storing large amounts of it in their soil. However, when they are drained—often for agriculture or forestry—they can become significant sources of CO₂, releasing the stored carbon into the atmosphere. The study examined data from 276 site-years across 114 peatlands in temperate and boreal regions, including Germany, Estonia, France, the United Kingdom, and North America. It found that lower water levels in peatlands make CO₂ emissions more sensitive to temperature increases, while maintaining higher water levels can reduce this sensitivity. The findings were published in the journal Nature Communications. To analyze the complex relationships between CO₂ emissions, water levels, and temperature, the researchers used explainable machine-learning techniques. These methods allowed them to study how these factors interact in a nonlinear way. The study found that raising the water table from very low levels—specifically, to less than 60–75 centimeters (about 2–2.5 feet) below the surface—can significantly reduce CO₂ emissions. The researchers identified that water tables at 20 centimeters (about 8 inches) below the surface or higher would be most effective in minimizing emissions. Daily data from 113 site-years with CO₂ measurements further supported these findings. Higher water levels were associated with a reduced impact of high temperatures on CO₂ emissions. Conversely, when the water table was low, rising temperatures had a more pronounced effect on emissions. The study highlights the potential of rewetting drained peatlands as a climate change mitigation strategy, especially as global warming continues. However, the researchers caution that a full assessment of peatlands’ role in the climate system must also consider other greenhouse gases, such as methane and nitrous oxide, which can be affected by rewetting. These gases can either increase or decrease depending on the specific conditions of the rewetted peatland, adding complexity to the overall climate impact.