This project uses a temperature gradient spanning 5 degrees Celsius to perform studies on responses to warming in a tropical system, including: soil carbon response, soil microbial community response, and carbon stock and flux responses for above and below ground carbon pools and fluxes. These studies take place in the Hawaii Experimental Tropical Forest and Hakalau Forest National Wildlife Refuge, across an area where canopy vegetation, soil type, soil moisture, and successional history are all relatively constant.
This project uses a model study system across the North Hilo-Hamakua Districts of Hawaii Island to model climate change and invasive species impacts on hydrological yield of 86 streams, and the potential response of yield to management including watershed restoration (invasive plant removal) and protection (fencing).
Across this system, total annual rainfall ranges from just under 2000mm per year to over 6000mm per year, but temperature, soils, and vegetation vary minimally. This project integrates hydrological modeling with spatial data on stream habitat condition (measured for the project area), critical habitat for plants and animals, ownership type and conservation status, cost of management, and management efficacy in order to create a watershed decision support tool (WDST). This tool will forecast: 1) climate change and invasive plant effects on stream flow; 2) threat management effects on stream flow; and 3) costs and hydrological benefits of management.
Maps of forest species-climate profiles were developed to help predict how forests, plant communities, and species may change on the landscape in response to climate change. Each species map depicts a ‘viability score’, which is an index on the interval zero to one that indicates how consistent the climate at a location is with the contemporary occurrence of a species. A low score at a given point in time or space indicates that the species does not occur (or very rarely occurs) in climates like those depicted at that location.
These maps provide information on where suitable future climate may be located for specific tree species under different climate scenarios.
Rising sea levels are being caused by a change in the volume of the world's oceans due to temperature increase, deglaciation (uncovering of glaciated land because of melting of the glacier), and ice melt. This data viewer can provide a preliminary look at sea level rise and how it might affect coastal resources across the United States (with the exception of Alaska and Louisiana). Data and maps can be used at several scales to help gauge trends and prioritize actions for different scenarios.
This data viewer can provide a preliminary look at sea level rise and how it might affect coastal resources across the United States (with the exception of Alaska and Louisiana). Data and maps can be used at several scales to help gauge trends and prioritize actions for different scenarios.
This synthesis integrates recent research concerning socioecological resilience in the Sierra Nevada, southern Cascade Range, and Modoc Plateau. Among the focal topics are forest and fire ecology; soils; aquatic ecosystems; forest carnivores; air quality; and the social, economic, and cultural components of socioecological systems. A central theme is the importance of restoring key ecological processes to mitigate impacts of widespread stressors, including changes in climate, fire deficit and fuel accumulations, air pollution, and pathogens and invasive species.
Ten headwater catchments in the southern Sierra Nevada have been studied since 2003 with regard to climate conditions, water yield, and water quality. Five of the catchments are in the current rain-snow interface climate zone and five are in the snow-dominated zone. Since there is only a 1,000 foot difference between these zones, the higher elevation catchments are expected to transition to a combination of rain and snow as climate changes in California. Studying how the lower elevation area functions gives us insight about how the higher elevation area will function with a changing climate; for the southern Sierra Nevada this is predicted to be less snow and more rain with about the same total amount of precipitation. This knowledge is very important as 50% of the surface water for California originates in the Sierra Nevada.
What will the rivers of the Pacific Northwest look like in the future? Will they be stable or unstable? Will they have salmon or other species? Will the waters be cold and clear or warm and muddy? These questions motivate our study of the effects of climate warming on streams draining the Cascade Mountains.
Previous studies have shown that snowpacks throughout the Cascades are highly vulnerable to warming temperatures, readily changing from snow to rain, and melting earlier. Less certain is how these changes are likely to affect streamflows, particularly in streams that derive much of their flow from deep groundwater and springs. These groundwater streams, which are currently characterized by very stable bed, banks, and vegetation, are particularly sensitive to increasing peak flows in the winter. We want to know how changing snowpacks and increased peak flows are likely to affect these channels, potentially changing their suitability as habitat for threatened species such as bull trout and spring Chinook. Results from our work, which include field and modeling components, will be used to guide management decisions affecting these streams: how dams are operated, whether water suppliers need to worry about turbidity, and how we should manage riparian vegetation.
A key challenge for resource and land managers is predicting the consequences of climate warming on streamflow and water resources. Over the last century in the western US, significant reductions in snowpack and earlier snowmelt have led to an increase in the fraction of annual streamflow during winter, and a decline in the summer. This study explores the relative roles of snowpack accumulation and melt, and landscape characteristics or 'drainage efficiency', in influencing streamflow. An analysis of streamflow during 1950-2010 for 81 watersheds across the western US indicates that summer streamflows in watersheds that drain slowly from deep groundwater and receive precipitation as snow are most sensitive to climate warming. During the spring, however, watersheds that drain rapidly and receive precipitation as snow are most sensitive to climate warming. Our results indicate that not all trends in the western US are associated with changes in snowpack dynamics; we observe declining streamflow in late fall and winter in rain-dominated watersheds as well. These empirical findings have implications for how streamflow sensitivity to warming is interpreted across broad regions.
Water stress represents a common mechanism for many of the primary disturbances affecting forests, and forest management needs to explicitly address the very large physiological demands that vegetation has for water. This study demonstrates how state-of-science ecohydrologic models can be used to explore how different management strategies might improve forest health.
Widespread threats to forests due to drought stress prompt re-thinking of priorities for water management on forest lands. In contrast to the widely held view that forest management should emphasize providing water for downstream uses, we argue that maintaining forest health in the face of environmental change may require focusing on the forests themselves and strategies to reduce their vulnerability to increasing water stress in the context of a changing climate. Management strategies would need to be tailored to specific landscapes but could include: a) thinning; 2) encouraging drought-tolerant species; 3) irrigation; and 4) strategies that make more water available to plants for transpiration. Hydrologic modeling reveals that specific management actions could reduce tree mortality due to drought stress. Adopting water conservation for vegetation as a priority for managing water on forest lands would represent a fundamental change in perspective and potentially involve tradeoffs with other downstream uses of water.
Environmental Protection Agency, Oregon State University
The Environmental Protection Agency’s (EPA) Climate Economics Branch (CEB) analyzes cost-effective strategies to reduce greenhouse gas (GHG) emissions, both in the U.S. and internationally. EPA relies on the Forest and Agricultural Sector Optimization Model with Greenhouse Gas (FASOM-GHG) model for analysis of GHG mitigation from the U.S. forest, agriculture and bioenergy sectors. This project will involve model development, results interpretation, testing, analyses, and documentation associated with the forestry and bioenergy sectors and related land use in the FASOM-GHG. The overarching objectives of the project are to make the forest sector portion more flexible, able to simulate a broader range of alternative bioenergy and CO2 sequestration policies, and to simplify the basic model code to reduce compilation and run time.
The Environmental Protection Agency’s (EPA) Climate Economics Branch (CEB) analyzes cost-effective strategies to reduce greenhouse gas (GHG) emissions, both in the U.S. and internationally. EPA relies on the Forest and Agricultural Sector Optimization Model with Greenhouse Gas (FASOM-GHG) model for analysis of GHG mitigation from the U.S. forest, agriculture and bioenergy sectors. The model is developed and maintained by the FASOM-GHG team, with expert members at Texas A&M University, Oregon State University, the Nicholas Institute at Duke University, Research Triangle Institute, Electric Power Research Institute, Environmental Protection Agency, USDA and the U.S. Forest Service.