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• 1. [Article] Carbon Dynamics in the Future Forest: the Importance of Long-Term Successional Legacy and Climate–Fire Interactions

  Understanding how climate change may influence forest carbon (C) budgets requires knowledge of forest growth relationships with regional climate, long-term forest succession, and past and future disturbances, ...

  Citation × Citation Citation Abstract Copy Title: Carbon Dynamics in the Future Forest: the Importance of Long-Term Successional Legacy and Climate–Fire Interactions Author: Loudermilk, E. Louise, Scheller, Robert M., Weisberg, Peter J., Yang, Jian, Dilts, Thomas E., Karam, Sarah L., Skinner, Carl Year: 2013 Understanding how climate change may influence forest carbon (C) budgets requires knowledge of forest growth relationships with regional climate, long-term forest succession, and past and future disturbances, such as wildfires and timber harvesting events. We used a landscape-scale model of forest succession, wildfire, and C dynamics (LANDIS-II) to evaluate the effects of a changing climate (A2 and B1 IPCC emissions; Geophysical Fluid Dynamics Laboratory General Circulation Models) on total forest C, tree species composition, and wildfire dynamics in the Lake Tahoe Basin, California, and Nevada. The independent effects of temperature and precipitation were assessed within and among climate models. Results highlight the importance of modeling forest succession and stand development processes at the landscape scale for understanding the C cycle. Due primarily to landscape legacy effects of historic logging of the Comstock Era in the late 1880s, C sequestration may continue throughout the current century, and the forest will remain a C sink (Net Ecosystem Carbon Balance > 0), regardless of climate regime. Climate change caused increases in temperatures limited simulated C sequestration potential because of augmented fire activity and reduced establishment ability of subalpine and upper montane trees. Higher temperatures influenced forest response more than reduced precipitation. As the forest reached its potential steady state, the forest could become C neutral or a C source, and climate change could accelerate this transition. The future of forest ecosystem C cycling in many forested systems worldwide may depend more on major disturbances and landscape legacies related to land use than on projected climate change alone. Title: Carbon Dynamics in the Future Forest: the Importance of Long-Term Successional Legacy and Climate–Fire Interactions Author: Loudermilk, E. Louise, Scheller, Robert M., Weisberg, Peter J., Yang, Jian, Dilts, Thomas E., Karam, Sarah L., Skinner, Carl Year: 2013 Understanding how climate change may influence forest carbon (C) budgets requires knowledge of forest growth relationships with regional climate, long-term forest succession, and past and future disturbances, such as wildfires and timber harvesting events. We used a landscape-scale model of forest succession, wildfire, and C dynamics (LANDIS-II) to evaluate the effects of a changing climate (A2 and B1 IPCC emissions; Geophysical Fluid Dynamics Laboratory General Circulation Models) on total forest C, tree species composition, and wildfire dynamics in the Lake Tahoe Basin, California, and Nevada. The independent effects of temperature and precipitation were assessed within and among climate models. Results highlight the importance of modeling forest succession and stand development processes at the landscape scale for understanding the C cycle. Due primarily to landscape legacy effects of historic logging of the Comstock Era in the late 1880s, C sequestration may continue throughout the current century, and the forest will remain a C sink (Net Ecosystem Carbon Balance > 0), regardless of climate regime. Climate change caused increases in temperatures limited simulated C sequestration potential because of augmented fire activity and reduced establishment ability of subalpine and upper montane trees. Higher temperatures influenced forest response more than reduced precipitation. As the forest reached its potential steady state, the forest could become C neutral or a C source, and climate change could accelerate this transition. The future of forest ecosystem C cycling in many forested systems worldwide may depend more on major disturbances and landscape legacies related to land use than on projected climate change alone. Close

• 2. [Article] Impacts of Fire and Climate Change on Long-Term Nitrogen Availability and Forest Productivity in the New Jersey Pine Barrens

  Increased wildfires and temperatures due to climate change are expected to have profound effects on forest productivity and nitrogen (N) cycling. Forecasts about how wildfire and climate change will affect ...

  Citation × Citation Citation Abstract Copy Title: Impacts of Fire and Climate Change on Long-Term Nitrogen Availability and Forest Productivity in the New Jersey Pine Barrens Author: Lucash, Melissa S., Scheller, Robert M., Kretchun, Alec M., Clark, Kenneth L., Hom, John Year: 2014 Increased wildfires and temperatures due to climate change are expected to have profound effects on forest productivity and nitrogen (N) cycling. Forecasts about how wildfire and climate change will affect forests seldom consider N availability, which may limit forest response to climate change, particularly in fire-prone landscapes. The overall objective of this study was to examine how wildfire and climate change affect long-term mineral N availability in a fire-prone landscape. We employed a commonly used landscape simulation model (LANDIS-II) in the New Jersey Pine Barrens, a landscape characterized by frequent small fires and fire-resilient vegetation. We found that fire had little effect on mineral N, whereas climate change and fire together reduced mineral N by the end of the century. Though N initially limited forest productivity, mineral N was no longer limiting after 50 years. Our results suggest that mineral N is resilient to fire under our current climate but not under climate change. Also, predictions that do not consider N limitation may underestimate short-term but not long-term productivity responses to climate change. Together these results illustrate the importance of including N dynamics when simulating the effects of climate change on forest productivity, particularly in fire-prone regions such as the New Jersey Pine Barrens. Title: Impacts of Fire and Climate Change on Long-Term Nitrogen Availability and Forest Productivity in the New Jersey Pine Barrens Author: Lucash, Melissa S., Scheller, Robert M., Kretchun, Alec M., Clark, Kenneth L., Hom, John Year: 2014 Increased wildfires and temperatures due to climate change are expected to have profound effects on forest productivity and nitrogen (N) cycling. Forecasts about how wildfire and climate change will affect forests seldom consider N availability, which may limit forest response to climate change, particularly in fire-prone landscapes. The overall objective of this study was to examine how wildfire and climate change affect long-term mineral N availability in a fire-prone landscape. We employed a commonly used landscape simulation model (LANDIS-II) in the New Jersey Pine Barrens, a landscape characterized by frequent small fires and fire-resilient vegetation. We found that fire had little effect on mineral N, whereas climate change and fire together reduced mineral N by the end of the century. Though N initially limited forest productivity, mineral N was no longer limiting after 50 years. Our results suggest that mineral N is resilient to fire under our current climate but not under climate change. Also, predictions that do not consider N limitation may underestimate short-term but not long-term productivity responses to climate change. Together these results illustrate the importance of including N dynamics when simulating the effects of climate change on forest productivity, particularly in fire-prone regions such as the New Jersey Pine Barrens. Close

• 3. [Article] Climate Change Effects on Northern Great Lake (USA) Forests: A Case for Preserving Diversity

  Under business as usual (BAU) management, stresses posed by climate change may exceed the ability of Great Lake forests to adapt. Temperature and precipitation projections in the Great Lakes region are ...

  Citation × Citation Citation Abstract Copy Title: Climate Change Effects on Northern Great Lake (USA) Forests: A Case for Preserving Diversity Author: Duveneck, Matthew Joshua, Scheller, Robert M., White, Mark A., Handler, Stephen D., Ravenscroft, Catherine Year: 2014 Under business as usual (BAU) management, stresses posed by climate change may exceed the ability of Great Lake forests to adapt. Temperature and precipitation projections in the Great Lakes region are expected to change forest tree species composition and productivity. It is unknown how a change in productivity and/or tree species diversity due to climate change will affect the relationship between diversity and productivity. We assessed how forests in two landscapes (i.e., northern lower Michigan and northeastern Minnesota, USA) would respond to climate change and explored the diversityproductivity relationship under climate change. In addition, we explored how tree species diversity varied across landscapes by soil type, climate, and management. We used a spatially dynamic forest ecosystem model, LANDIS-II, to simulate BAU forest management under three climate scenarios (current climate, low emissions, and high emissions) in each landscape. We found a positive relationship between diversity and productivity only under a high emissions future as productivity declined. Within landscapes, climate change simulations resulted in the highest diversity in the coolest climate regions and lowest diversity in the warmest climate region in Minnesota and Michigan, respectively. Simulated productivity declined in both landscapes under the high emissions climate scenario as species such as balsam fir (Abies balsamea) declined in abundance. In the Great Lakes region, a high emissions future may decrease forest productivity creating a more positive relationship between diversity and productivity. Maintaining a diversity of tree species may become increasingly important to maintain the adaptive capacity of forests. Title: Climate Change Effects on Northern Great Lake (USA) Forests: A Case for Preserving Diversity Author: Duveneck, Matthew Joshua, Scheller, Robert M., White, Mark A., Handler, Stephen D., Ravenscroft, Catherine Year: 2014 Under business as usual (BAU) management, stresses posed by climate change may exceed the ability of Great Lake forests to adapt. Temperature and precipitation projections in the Great Lakes region are expected to change forest tree species composition and productivity. It is unknown how a change in productivity and/or tree species diversity due to climate change will affect the relationship between diversity and productivity. We assessed how forests in two landscapes (i.e., northern lower Michigan and northeastern Minnesota, USA) would respond to climate change and explored the diversityproductivity relationship under climate change. In addition, we explored how tree species diversity varied across landscapes by soil type, climate, and management. We used a spatially dynamic forest ecosystem model, LANDIS-II, to simulate BAU forest management under three climate scenarios (current climate, low emissions, and high emissions) in each landscape. We found a positive relationship between diversity and productivity only under a high emissions future as productivity declined. Within landscapes, climate change simulations resulted in the highest diversity in the coolest climate regions and lowest diversity in the warmest climate region in Minnesota and Michigan, respectively. Simulated productivity declined in both landscapes under the high emissions climate scenario as species such as balsam fir (Abies balsamea) declined in abundance. In the Great Lakes region, a high emissions future may decrease forest productivity creating a more positive relationship between diversity and productivity. Maintaining a diversity of tree species may become increasingly important to maintain the adaptive capacity of forests. Close

• 4. [Article] The Effects of Global Change Upon United States Air Quality

  To understand more fully the effects of global changes on ambient concentrations of ozone and particulate matter with aerodynamic diameter smaller than 2.5 μm (PM2.5) in the United States (US), we conducted ...

  Citation × Citation Citation Abstract Copy Title: The Effects of Global Change Upon United States Air Quality Author: Gonzalez-Abraham, Rodrigo, Chung, Serena H., Avise, Jeremy C., Lamb, Brian, Salathé, Eric P., Jr., Nolte, Christopher G., Loughlin, Dan, Guenther, Alex, Wiedinmyer, Christine, Duhl, Tiffany, Zhang, Yang, Streets, David G. Year: 2015 To understand more fully the effects of global changes on ambient concentrations of ozone and particulate matter with aerodynamic diameter smaller than 2.5 μm (PM2.5) in the United States (US), we conducted a comprehensive modeling effort to evaluate explicitly the effects of changes in climate, biogenic emissions, land use and global/regional anthropogenic emissions on ozone and PM2.5 concentrations and composition. Results from the ECHAM5 global climate model driven with the A1B emission scenario from the Intergovernmental Panel on Climate Change (IPCC) were downscaled using the Weather Research and Forecasting (WRF) model to provide regional meteorological fields. We developed air quality simulations using the Community Multiscale Air Quality Model (CMAQ) chemical transport model for two nested domains with 220 and 36 km horizontal grid cell resolution for a semi-hemispheric domain and a continental United States (US) domain, respectively. The semi-hemispheric domain was used to evaluate the impact of projected global emissions changes on US air quality. WRF meteorological fields were used to calculate current (2000s) and future (2050s) biogenic emissions using the Model of Emissions of Gases and Aerosols from Nature (MEGAN). For the semi-hemispheric domain CMAQ simulations, present-day global emissions inventories were used and projected to the 2050s based on the IPCC A1B scenario. Regional anthropogenic emissions were obtained from the US Environmental Protection Agency National Emission Inventory 2002 (EPA NEI2002) and projected to the future using the MARKet ALlocation (MARKAL) energy system model assuming a business as usual scenario that extends current decade emission regulations through 2050. Our results suggest that daily maximum 8 h average ozone (DM8O) concentrations will increase in a range between 2 to 12 parts per billion (ppb) across most of the continental US. The highest increase occurs in the South, Central and Midwest regions of the US due to increases in temperature, enhanced biogenic emissions and changes in land use. The model predicts an average increase of 1–6 ppb in DM8O due to projected increase in global emissions of ozone precursors. The effects of these factors are only partially offset by reductions in DM8O associated with decreasing US anthropogenic emissions. Increases in PM2.5 levels between 4 and 10 μg m−3 in the Northeast, Southeast, Midwest and South regions are mostly a result of increase in primary anthropogenic particulate matter (PM), enhanced biogenic emissions and land use changes. Changes in boundary conditions shift the composition but do not alter overall simulated PM2.5 mass concentrations. Title: The Effects of Global Change Upon United States Air Quality Author: Gonzalez-Abraham, Rodrigo, Chung, Serena H., Avise, Jeremy C., Lamb, Brian, Salathé, Eric P., Jr., Nolte, Christopher G., Loughlin, Dan, Guenther, Alex, Wiedinmyer, Christine, Duhl, Tiffany, Zhang, Yang, Streets, David G. Year: 2015 To understand more fully the effects of global changes on ambient concentrations of ozone and particulate matter with aerodynamic diameter smaller than 2.5 μm (PM2.5) in the United States (US), we conducted a comprehensive modeling effort to evaluate explicitly the effects of changes in climate, biogenic emissions, land use and global/regional anthropogenic emissions on ozone and PM2.5 concentrations and composition. Results from the ECHAM5 global climate model driven with the A1B emission scenario from the Intergovernmental Panel on Climate Change (IPCC) were downscaled using the Weather Research and Forecasting (WRF) model to provide regional meteorological fields. We developed air quality simulations using the Community Multiscale Air Quality Model (CMAQ) chemical transport model for two nested domains with 220 and 36 km horizontal grid cell resolution for a semi-hemispheric domain and a continental United States (US) domain, respectively. The semi-hemispheric domain was used to evaluate the impact of projected global emissions changes on US air quality. WRF meteorological fields were used to calculate current (2000s) and future (2050s) biogenic emissions using the Model of Emissions of Gases and Aerosols from Nature (MEGAN). For the semi-hemispheric domain CMAQ simulations, present-day global emissions inventories were used and projected to the 2050s based on the IPCC A1B scenario. Regional anthropogenic emissions were obtained from the US Environmental Protection Agency National Emission Inventory 2002 (EPA NEI2002) and projected to the future using the MARKet ALlocation (MARKAL) energy system model assuming a business as usual scenario that extends current decade emission regulations through 2050. Our results suggest that daily maximum 8 h average ozone (DM8O) concentrations will increase in a range between 2 to 12 parts per billion (ppb) across most of the continental US. The highest increase occurs in the South, Central and Midwest regions of the US due to increases in temperature, enhanced biogenic emissions and changes in land use. The model predicts an average increase of 1–6 ppb in DM8O due to projected increase in global emissions of ozone precursors. The effects of these factors are only partially offset by reductions in DM8O associated with decreasing US anthropogenic emissions. Increases in PM2.5 levels between 4 and 10 μg m−3 in the Northeast, Southeast, Midwest and South regions are mostly a result of increase in primary anthropogenic particulate matter (PM), enhanced biogenic emissions and land use changes. Changes in boundary conditions shift the composition but do not alter overall simulated PM2.5 mass concentrations. Close