Evaluation of national Greenhouse Gas Removal potential under a changing climate using a process-based land surface model

Abstract. Global warming and climate change caused by greenhouse gas emissions (GHG) will have multiple impacts on forest ecosystems. As the UK’s currently planned contribution to global efforts to mitigating these impacts, the Climate Change Act has set a goal of net zero emissions of GHG by 2050. A core part of the strategy to meet this target is to use afforestation and forestry management to implement large-scale Greenhouse Gas Removal (GGR). These measures will need to be resilient to some level of climate change even if the international community successfully meets the goals of the Paris Agreement in limiting global warming. However, the effectiveness of afforestation as a GGR strategy is difficult to fully evaluate with standard empirical models due to a myriad of changing environmental conditions. Here we use the process-based land surface model, coupled to a model of large-scale forest demography (JULES-RED). We focus on a low climate change scenario, which would yield peak global warming close to 2^oC. We project that widespread Sitka Forest afforestation could potentially sequester 15 MtCO₂ annually by 2080 assuming a plantation rate of 30,000 ha year^-1 from 2025 to 2050. If the world fails to meet the goals of the Paris Agreement, UK woodlands will need to be resilient to more severe regional climate changes and the plantation locations will need be selected more precisely.