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Chapter 2: Effects of climatic variability and change. In Effects of Climate Variability and Change on Forest Ecosystems: A Comprehensive Science Synthesis for the U.S. Forest Sector; General Technical Report PNW-GTR-870, Washington DC
Citation:
Ryan, M., J. Vose, M. Ayres, L. Band, C. Ford, P. Hanson, J. Hicke, L. Iverson, B. Kerns, S. Klein, J. Littell, C. Luce, D. McKenzie, D. Wear, AND A. Weed. Chapter 2: Effects of climatic variability and change. In Effects of Climate Variability and Change on Forest Ecosystems: A Comprehensive Science Synthesis for the U.S. Forest Sector; General Technical Report PNW-GTR-870, Washington DC. USDA Forest Service, 2012.
Impact/Purpose:
The purpose of the National Climate Assessment is to integrate, evaluate and interpret the findings of the USGCRP. The National Climate Assessment - Forest Sector Technical Report analyzes the effects of global change on forests in the United States. It incorporates advances in our understanding of climate change science and assesses the potential impacts and vulnerabilities to forests in the United States. Future changes in forest ecosystems will occur on both public and private lands and will challenge our ability to provide ecosystem services desired by society, especially as human populations continue to grow and demands for ecosystem services increase. Climate-change effects in forests are likely to cause losses of ecosystem services in some areas, but may also improve and expand ecosystem services in others. Some areas may be particularly vulnerable because current infrastructure and resource production are based on past climate and steady-state conditions. Any change in forest ecosystems that affects water resources will typically result in a significant loss of ecosystem services.
Description:
Climate profoundly shapes forests. Forest species composition, productivity, availability of goods and services, disturbance regimes, and location on the landscape are all regulated by climate. Much research attention has focused on the problem of predicting the response of forests to changing climate, elevated atmospheric carbon dioxide (CO2) concentrations, and nitrogen deposition, deepening our understanding since the publication of the last assessment (Ryan et al. 2008). We have many new examples of how changes in climate over the past 30 years have affected forest ecosystems, including long-term monitoring data on forest change, multi-factor experiments that document the potential interactions between temperature and elevated CO2, and new modeling approaches that predict the impact of projected changes in climate on forest ecosystems, their goods and services, and their disturbance regimes. Climate projections are being done on a finer spatial scale, and global climate models include more detail and feedbacks with terrestrial processes. Downscaled estimates from these models are more readily available and have been used for more regional and local assessments. Despite the large amount of new research, this new information has not substantially altered the primary predictions made in the last assessment (Ryan et al. 2008). In this assessment, we have added Chapter 2: Climate Change Effects -- 2 more detail about the impacts covered in the last assessment (especially altered disturbance regimes and potential impacts on hydrologic processes), provided more information about regional effects, and covered additional topics.