This paper reviews current scientific knowledge on projected climate changes in the Pacific Northwest, plant responses and adaptability to these changes, and recent model projections of vegetation responses to future climate change scenarios, with emphasis on five major biome types. It includes a discussion of current approaches and resources for developing climate change adaptation strategies, including restoring historical vegetation structure and composition, promoting resistance to change, promoting resilience to change, and facilitating anticipated responses to change.
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.
In these collected papers, leading scientists, resource managers and policy specialists explore the implications of climate change and other manifestations of the Anthropocene on the management of wildlife habitat, biodiversity, water, and other resources, with particular attention to the effects of wildfire. Recommendations include the need for a supporting institutional, legal, and policy framework that is not just different but more dynamic, to facilitate resource management adaptation and preparedness in a period of accelerating environmental change.
The North Cascadia Adaptation Partnership (NCAP) is a science-management partnership that has worked with numerous stakeholders over 2 years to identify climate change issues relevant to resource management in the North Cascades, and to find solutions that will help the diverse ecosystems of this region transition into a warmer climate. The NCAP provided education, conducted a climate change vulnerability assessment, and developed adaptation options for federal agencies that manage 2.4 million hectares in north-central Washington.
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.
This assessment evaluates the vulnerability of forest ecosystems in the Laurentian Mixed Forest Province of northern Wisconsin and western Upper Michigan under a range of future climates. Over 40 managers and researchers contributed to this report from the Climate Change Response Framework, from various federal, state, tribal, non-profit, academic, and private organizations.
This assessment evaluates the vulnerability of forest ecosystems in Minnesota to a range of future climates. Information on current forest conditions, observed climate trends, projected climate changes, and impacts to forest ecosystems was considered in order to draw conclusions on climate change vulnerability.
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.