Assessment of responses and impacts must distinguish between transient and equilibrium situations. Because forests are composed of long-lived organisms, responses to climate change and resulting impacts may take a long time to propagate through the system. To the extent that global change (climate and land-use change) proceeds faster than the life cycle of many late-succession trees, transient responses will predominate. Forest structure today is the result of activities and events that occurred many years (>100) ago; hence, responses and parameters measured today are not in equilibrium with present conditions. Many state variables, such as carbon pools, are expected to change with a time delay. Furthermore, forest responses to climate change and resulting impacts may extend longer than the change in climate.

5.6.3.1. Responses and Impacts: Carbon Storage

There are numerous ways in which forests respond to climate change and other pressures. These responses affect their ability to store carbon. Responses include changes in species distribution, NPP, NEP, and NBP; pests and disease outbreaks; and elevated CO₂, as well as changes in climate variability and weather extremes.

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