Explore interventions

Fire is important to the healthy functioning of boreal ecosystems. However, as wildfires increase, they release greater amounts of GHGs into the atmosphere, contributing to climate change. While boreal fires typically contribute 10% of global CO2 emissions, in 2021, an extreme fire year, they accounted for 23% of global emissions (Zheng et al. 2023). Particulate matter in wildfire smoke (soot or black carbon, see also Black carbon mitigation) can also reduce albedo on sea ice and glaciers, enhancing ice melt (e.g., Aubry-Wake et al. 2022). Wildfires are projected to increase in both frequency and intensity over the coming decades (UNEP 2022). By 2050, wildfires in North American boreal forests alone could contribute close to 12 Gt CO2, almost 3% of the remaining global CO2 emissions to keep temperatures to below 1.5oC (Phillips et al. 2022a).

Although the rate of deforestation has slowed over the last few decades, the world is still losing forest cover (FAO 2020). Adequate management, protection, and restoration of existing forests, and the planting of unforested areas, play a crucial role in climate mitigation scenarios (IPCC AR6 WG3), and many countries now include forests in their climate mitigation targets (NDCs).The Northern and Arctic regions are essential in this endeavor since they are home to large swaths of boreal forests that make up 27% of total global forest area (FAO 2020).

In many Arctic and Northern regions, domesticated or semi-domesticated reindeer (Rangifer tarandus) are the only large herbivores (Uboni et al. 2016). Reindeer play a crucial role in these ecosystems and in the livelihoods and traditions of multiple local and indigenous populations. In light of the major impact of climate change in the Arctic, the capacity of large herbivores to mitigate some of these effects is being explored. Herbivores can have different climate positive effects as they can reduce shrubification and slow ecosystem responses to climate change (Olofsson and Post 2018; Happonen et al. 2021), modify summer and winter surface albedo (te Beest et al. 2016), trample winter snow to thicken permafrost (Beer et al. 2020; Windirsch et al. 2022), and increase biomass and soil carbon sequestration (Ylänne et al. 2018; Ylänne et al. 2021; see also soil management).

Natural climate solutions like conservation or restoration can significantly contribute to climate change mitigation efforts (Griscom et al. 2017). One such category of natural climate solutions is re-wilding.

Wetlands and peatlands play important roles in global carbon cycles. Wetlands are areas that are seasonally covered by water. Globally mangroves are often the main topic of focus when it comes to wetlands (IPCC AR6 WG3, 2022, 7.4.2.8). In the Arctic and Northern regions, peatlands are important wetland elements, and will be the focus of what follows. Such peatlands are very carbon rich and store carbon in biomass below and above ground and in soil carbon. Although they only make up 3% of the Earth’s surface, peatlands store up to 21% of terrestrial carbon, and damaged peatlands contribute close to 5% of anthropogenic CO2 emissions (Leifeld et al. 2019). Peatland drainage between 1850 and 2015 has globally already released 80 Gt CO2-eq, and this figure may climb to 250 Gt CO2-eq by 2100 (Leifeld et al. 2019).

Compared to the global state of such areas, Arctic and Northern wetlands and peatlands remain relatively intact (UNEP 2021), and only around 2% of boreal peatlands are currently converted into croplands (Leifeld and Menichetti 2018). However, increasing attention is being paid to the importance of restoring destroyed areas, which make up 78% of total global peatlands, and preserving endangered ones, especially in light of the effects of climate change on such ecosystems. The Resilience and Management of Arctic Wetlands notes (CAFF 2021) therefore highlight the need for increased wetlands resilience to protect against future damage.

Terrestrial carbon can be stored in biomass above or below the ground, and in soils themselves. Soil organic matter can form differently, and have different amounts of plant and microbial components depending on the availability of water (Cotrufo and Lavallee, 2022). The large amounts of the Earth that have been brought under cultivation over the past 12.000 years have significantly degraded soil carbon levels, and have released some 110 billion metric tons of carbon (Sanderman et al. 2017). Soil security and health is increasingly being recognised as essential for planetary health (Kopittke et al. (2022).

There have been several isolated suggestions to mitigate permafrost thaw or influence the thaw processes in the active layer by physically covering the surface with materials (see for example https://groups.google.com/g/geoengineering/c/u2b9Xb5B0C8/m/aXQia-nNDbcJ) in a similar way to how glaciers might be preserved (see Glacier Insulation, and Passive Radiative Cooling). Although different materials have been suggested, these have not been worked out further, and are likely to be a very costly, and impractical solution.

Thermosyphon technologies that passively cool soils if the air temperature is colder than surface temperatures have been used on a smaller scale to stabilize permafrost that supports infrastructure (Xu and Goering, 2008).

Passive daytime radiative cooling (PDRC) promises to provide energy free cooling through thermally-emissive surfaces that reflect incoming solar radiation whilst simultaneously enhancing longwave heat transfer to space through the infrared window of the atmosphere (8–13 µm) (Yin et al. 2020).

Surface albedo has a significant impact on global climate (Zhang et al. 2022). Plants play an important role in this. Matthews et al. (2003), for example, estimate that the spread of agriculture has led to a global cooling of around 0.17°C, as agricultural crops tend to have a higher albedo than wild vegetation (Monteith and Unsworth 1990).

The built environment takes up an ever greater portion of the earth’s surface. This mostly unused surface area could be coated in albedo enhancing paints or material which would allow them to reflect incoming sunlight.

Some have suggested that it might be possible to capture methane or methane hydrates and transform it into useful materials.