Climate Change Impacts
While the climate patterns in North America have been consistent for the past few thousand years, in many places these patterns are now beginning to change. These changes have profound implications for natural communities.
Explore this page:
- Implications of Climate Change for Natural Communities
- How Animals and Plants Are Responding to Climate Change
- Climate Change and Park Management
Implications of Climate Change for Natural Communities
A detailed treatment of global climate change is beyond the scope of this guide. However, it is clear that changes in climate can have far-reaching implications on natural communities anywhere in the world.
The natural ranges of plant and animal species are typically governed by climate, so the climate of any location affects the pool of species found there.
For the past several decades, the United States has seen more record high temperatures and fewer record low temperatures. Precipitation patterns have changed as well.
What are the implications of these changes? It’s a complex question with no simple answer, but here are some possibilities:
- In some places, climate change may translate into more severe drought, resulting in stress to trees and vulnerability to expanded insect or disease outbreaks.
- Wildfires may become more frequent and burn more intensely.
- More severe storms may result in more severe flooding, or blow down more trees and open larger canopy gaps.
- In some places, climate changes may enable non-native invasive species to expand their ranges and replace native species.
- Change in seasonal temperature may also disrupt interactions among plants and animals, such as the timing of blooms with the spring arrival of insect or bird pollinators.
How Animals and Plants Are Responding to Climate Change
Some populations of plant and animal species are shifting their ranges in response to changes in temperature and precipitation. Some species are making shifts in elevation, some in latitude.
In the Great Basin of the American West, the hamster-sized pika has been shifting its range higher at a rate of 145 meters per decade. It has become locally extinct in many areas.
Among 40 songbird species in the West studied by researchers at the University of Massachusetts-Amherst, most have shifted their ranges—some northward and some to higher elevations.
Other species are not able to respond as quickly, for many reasons. A little fish that lives in just one watershed cannot very easily move to another. Trees with long life cycles can only shift their range slowly.
Depending on the responses of different plants and animals, one can expect that the mix of species in natural communities will also change. Some changes may occur quite gradually—over many decades—as long-lived individuals, like many trees, can no longer successfully regenerate. In other cases, change may occur more rapidly, with sudden local extinctions, or where communities can no longer recover from natural disturbances and rapidly transform into new species assemblages.
Climate Change and Park Management
Ecologists and managers have often looked to the past to understand the natural composition and processes for natural communities, and then used that knowledge to recover or maintain natural communities.
Now they are increasingly challenged to look to the future, and to use those predictions to inform management practices that will maintain natural communities that function well today and will continue to do so tomorrow.