The role of boreal forests in climate mitigation
Conserving and increasing the carbon uptake and stock in forests is a key mitigation measure to limit global warming in line with the ambitions of the Paris Agreement. Global emission pathways consistent with limiting the global temperature increase below 1.5°C and 2°C rely heavily on land-based measures through varying degrees of afforestation/reforestation, reduced deforestation, and bioenergy. According to the 2019 IPCC special report on land and climate, up to 12 million km2 more forested area is projected globally by 2050. Simultaneously, forests are facing a range of other demands, including biodiversity and bioeconomy.
Through the project «Quantifying climate Impacts of Future Forest management strategies in Norway (QUIFFiN)», scientists from CICERO, NTNU and NIBIO are working to strengthen the knowledge about how vegetation changes following forest management can affect climate when considering a broad set of relevant mechanisms. Such knowledge is needed to understand the potential role of Norwegian forests for meeting the 2°C target.
Alternative management models can result in different changes in the structure and extent of the forest. In addition to the update and release of CO2, changes in vegetation affect climate through a range of mechanisms, including through increased or decreased surface albedo, or reflectivity. Results from the project also suggest that large-scale changes in forest cover can increase or decrease the amount of so-called secondary organic particles in the atmosphere, particles which affects the Earth?s energy balance. The albedo effect is particularly important at high, northern latitudes, affecting the net climate effect of vegetation changes. However, as demonstrated in a recent review paper published in Atmospheric Chemistry and Physics, weighting the effect of albedo changes against that due to CO2 fluxes is challenging.
Recent calculations suggest a wide range in future scenarios for wood outtake volumes in Norway, depending on underlying assumptions about socio-economic development and climate and energy polices. Furthermore, different management strategies, such as more intensive harvest and species change, can be used to meet increased demand for wood and higher outtakes. These can in turn change the forest in very different ways and including detailed information about forest characteristics is important for quantification of subsequent climate effects. Moreover, assessing the local climate impacts of vegetation changes requires confidence in the models' ability to represent local conditions. By analyzing multi-model output, QUIFFiN researchers are studying how current regional climate models represent observed snow cover and distribution, and the associated snow-atmosphere interactions.
By combining ecosystem modeling and high-resolution climate modeling, QUIFFiN investigates the interaction between forest changes and climate in detail in order to contribute knowledge of relevance for sustainable forestry in Norway.
The international community has agreed to limit the global temperature increase to 2°C above the pre-industrial levels. This will require a large-scale shift away from the fossil economy towards one based on renewable materials and energy, such as biomass.
Forests can play multiple roles in climate mitigation, such as sequestering carbon or provision of energy. Changes in forest management can alter the distribution, structure, and functioning of terrestrial ecosystems, which in turn affect climate. Whether a certain type of land use or management change will result in a net cooling or warming contribution for the regional and global climate is highly dependent on site specific conditions and vegetation. As a consequence detailed data about vegetation characteristics is essential. Moreover, the quantification of regional and global climate responses requires both high resolution modeling and inclusion of a broad set of the mechanisms which affect climate on different time scales.
Currently, little or no information exist about the regional climate response to changes in forest cover and structure following future forest management strategies. This limits our ability to confidently determine which management options lead to climate benefits.
By combining environmental systems analysis and detailed ecosystem modeling with high-resolution climate modeling, QUIFFiN will:
- Provide detailed data for vegetation changes under various future strategies for management of the Norwegian forest
- Improve our holistic understanding and quantify climate impacts from the regional to global scale following vegetation changes in a Norway
- Identify possible win-win solutions of forest management practices for simultaneous provision of bio-resources and mitigation of climate change
QUIFFiN aims to provide robust scientific knowledge of relevance for designing policies for climate mitigation and sustainable management of Norwegian forest resources.