Spatially explicit modeling of 1992–2100 land cover and forest stand age for the conterminous United States

Abstract

Information on future land-use and land-cover (LULC) change is needed to analyze the impact of LULC change on ecological processes. The U.S. Geological Survey has produced spatially explicit, thematically detailed LULC projections for the conterminous United States. Four qualitative and quantitative scenarios of LULC change were developed, with characteristics consistent with the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emission Scenarios (SRES). The four quantified scenarios (A1B, A2, B1, and B2) served as input to the forecasting scenarios of land-use change (FORE-SCE) model. Four spatially explicit data sets consistent with scenario storylines were produced for the conterminous United States, with annual LULC maps from 1992 through 2100. The future projections are characterized by a loss of natural land covers in most scenarios, with corresponding expansion of anthropogenic land uses. Along with the loss of natural land covers, remaining natural land covers experience increased fragmentation under most scenarios, with only the B2 scenario remaining relatively stable in both the proportion of remaining natural land covers and basic fragmentation measures. Forest stand age was also modeled. By 2100, scenarios and ecoregions with heavy forest cutting had relatively lower mean stand ages compared to those with less forest cutting. Stand ages differed substantially between unprotected and protected forest lands, as well as between different forest classes. The modeled data were compared to the National Land Cover Database (NLCD) and other data sources to assess model characteristics. The consistent, spatially explicit, and thematically detailed LULC projections and the associated forest stand-age data layers have been used to analyze LULC impacts on carbon and greenhouse gas fluxes, biodiversity, climate and weather variability, hydrologic change, and other ecological processes.

Integrated climate and land use change scenarios for California rangeland ecosystem services: wildlife habitat, soil carbon, and water supply

“…The FORE-SCE LULC change model was used to distribute the demand for future regional LULC change on the landscape for each scenario (Sohl et al , 2014. Demand was allocated spatially according to probability of occurrence raster datasets (suitability surfaces).…”

Grand Challenges in Understanding the Interplay of Climate and Land Changes

“…Given the variety of socioeconomic factors that affect land use and their interplay with climate change, modeling the potential impacts of climate change on land use is complicated (Rindfuss et al 2008;Brown et al 2013). Ideally, a modeling framework would include feedbacks between climatological, economic, and policy driving forces from local to global scales (Sohl et al 2010;Rounsevell et al 2012;Meyfroidt et al 2013). However, current land-use modeling efforts suffer from 1) an incomplete representation of processes affecting land-use change, 2) an inability to represent the feedbacks between driving forces operating at multiple scales, and 3) a limited ability to assess modeling uncertainties.…”

“…Similarly, econometric models have been widely used within the U.S. to project regional-scale land use based on concepts of optimizing economic return (Murray et al 2005;Lubowski et al 2006;Radeloff et al 2012), yet these too often neglect the impacts of climate change. Overall, it is impossible to perfectly represent all biophysical and socioeconomic processes that affect land-use change across all relevant spatial and temporal scales (Moreira et al 2009;Sohl et al 2010), and each of the modeling frameworks described here necessarily sacrifices the representation of some processes or geographic scale. The challenge for future applications is to include pertinent driving forces operating at multiple scales, while reducing model complexity to a reasonable level and maintaining the capability to quantify uncertainties (Sohl and Claggett 2013).…”

“…In an attempt to link global-level driving forces to local-scale, land-use change, more recent modeling efforts have attempted to downscale IAMs and climate impacts on land-use systems to much finer spatial scales for both Europe ) and for the United States (Sleeter et al 2012;Sohl et al 2014;West et al 2014). However, the direct modeling of feedbacks between the bottom-up and top-down drivers of land use and climate change remains a major challenge (Sohl and Claggett 2013).…”

“…In an attempt to link global-level driving forces to local-scale, land-use change, more recent modeling efforts have attempted to downscale IAMs and climate impacts on land-use systems to much finer spatial scales for both Europe ) and for the United States (Sleeter et al 2012;Sohl et al 2014;West et al 2014). However, the direct modeling of feedbacks between the bottom-up and top-down drivers of land use and climate change remains a major challenge (Sohl and Claggett 2013). Integrated approaches that attempt to link models across disciplines typically do so in a ''waterfall'' approach (van Delden and McDonald 2010), where output from one model is used as input to another model, without any real-time linkage or feedback between models (Sohl and Claggett 2013).…”