Policy Perspective on the Role of Forest Sector Modeling.

Representing 30% of the world’s ice-free land surface area (International Panel on Climate Change, 2019; Food and Agriculture Organization, 2015), forests will continue to play a large role in global environmental systems, economies, and policies, including efforts to reduce greenhouse gas (GHG) emissions – but the extent of that future role is largely unknown. Global forests currently provide important ecological (e.g., habitat, water filtration) and economic [e.g., supported a global forest products economy valued over $US247 billion in 2017 (Food and Agriculture Organization, 2019)] services, and they provided a net global carbon sink over the last century (Nabuurs et al., 2007; Houghton, 2008; Smith et al., 2014). Heightened recognition of the importance of forests in sustainable development and mitigation efforts is reflected in recent reports (e.g., International Panel on Climate Change, 2019; Rogelj et al., 2018; U.S. Global Change Research Program, 2018) as well as commitments to reduce GHGs (e.g., United Nations Framework Convention on Climate Change, 2015). Forest-based mitigation investments represent vast potential GHG mitigation opportunities (Van Winkle et al., 2017; U.S. Environmental Protection Agency, 2005; Sohngen and Mendelsohn, 2003) that are inexpensive relative to other sectors (Rose et al., 2012). In the context of global commitments, land use sector could yield 20%–25% of total emission reductions (Forsell et al., 2016). In the U.S., there has been increased attention to the role of forests in GHG mitigation (U.S. Department of State, 2014; White House, 2016; U.S. Department of Agriculture, 2015) and economic development efforts, including advancement of the U.S. bioeconomy (Biomass Research and Development Board, 2016). Consideration of potential future outcomes from land use, land use change1 and forestry (LULUCF) is integral for achieving these policy goals, especially GHG mitigation goals, as the evolution of forests over time (in terms of size, health, how they are managed and their ability to sequester and store carbon) will have important implications for whether or not commitments can be met (Baker et al., 2017; Van Winkle et al., 2017; International Panel on Climate Change, 2019). It is therefore essential that decisionmakers and the research communities that support them – such as the forest sector modeling community – develop the best data and state-of-the-art tools for evaluating potential future forest sector outcomes to inform policy development. Contributions by the papers in this special issue advance our understanding of forest system dynamics and forest sector