Carbon sequestration and storage are vital in complementing the reduction of anthropogenic greenhouse gas (GHG) emissions to mitigate climate change. Globally, forests are recognized for their significant carbon sequestration and storage potential, serving as a natural solution to climate change. This study examines the temporal dynamics of carbon sequestration in the forests of Stockholm County, Sweden, focusing on tree species composition, forest age, and local hydroclimatic conditions. The research underscores the variability in sequestration capacity across different forest types and ages, with middle-aged forests identified as key contributors to carbon capture. Projections indicate a 27% increase in sequestration potential by 2040, driven by natural forest aging and expansion, provided current forest management practices are maintained. However, this potential increase may be influenced by land use change, climate change impacts, and forest management strategies. Effective forest management is important to enhance and sustain carbon sequestration capacities, aiding Stockholm County in achieving its net zero emissions goal by 2040. Further research is necessary to refine sequestration estimates and optimize forest management practices for long-term climate mitigation.