When permafrost soils thaw in the Arctic, they release not just CO₂ but also the more potent greenhouse gas methane. To better predict future emissions, CLICCS is investigating various processes in detail, so that they can be represented as accurately as possible in climate models

In soils, a thicker active layer and increased subsoil temperatures promote the decomposition of organic matter, and with it, the production of methane. In addition to the carbon released as CO₂, methane makes up nearly seven percent of emissions in the moist tundra; in dry soils, it accounts for less than 0.3 percent.

Taken together, these findings paint a different picture: moist and dry soils emit roughly the same amount of methane when cloud formation is also factored in. Heavier cloud cover forms over moist soils, producing lower temperatures below. In turn, this reduces the overall output of the carbon cycle, so that less methane is released from moist soils.

And how are the Arctic’s extensive pond and lake landscapes reacting? Here, changes in vegetation are responsible for the majority of additional methane emissions. Thanks to warmer temperatures, the vegetation in and around the ponds is becoming lusher. This in turn increases emissions: like a straw, the plants’ long stems pass methane released by the soil directly on to the atmosphere.

How can harvests remain stable despite higher future temperatures? In a dialogue with local farmers, CLICCS is working to develop efficient agricultural solutions. Field experiments conducted in Namibia have shown that, when sown together with high-efficiency bacteria, cowpea harvests can be doubled. Local farmers are willing to make the change.