Climate is constantly changing, prompting natural and managed ecosystems to adjust. As a natural process, adaptation refers to the reactive changes that species and ecosystems make in response to environmental changes. With human intervention, adaptation refers to management actions and decisions that help ecological, social, and economic systems accommodate challenges imposed by climate change. Management actions can be developed to anticipate climate change and associated changes in natural disturbances such as fire and insects. Adaptation options for resource management may focus on the short term to forestall climate change impacts or on the long term to anticipate and manage ecosystem change.