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Deserts and grasslands will need to move rapidly to adapt to the changing climate.

From beetles to barnacles, pikas to pine warblers, many species are already on the move in response to shifting climate regimes. But how fast will they - and their habitats - have to move to keep pace with global climate change over the next century?

In a new study, a team of scientists including Dr. Healy Hamilton from the California Academy of Sciences have calculated that on average, ecosystems will need to shift about 0.42 kilometers per year to keep pace with changing temperatures across the globe.

How well particular species can survive rising worldwide temperatures attributed to excess levels of heat-trapping "greenhouse" gases emitted by human activity hinges on those species' ability to migrate or adapt in place. The farther individual species -- from shrubs and trees to insects, birds and mammals -- need to move to stay within their preferred climate, the greater their chance of extinction.

"Things are on the move, faster than we anticipated," says Dr. Hamilton. "This rate of projected climate change is just about the same as a slow-motion meteorite in terms of the speed at which it's asking a species to respond."

Mountainous habitats will be able to move more slowly, since a modest move up or down slope can result in a large change in temperature. However, flatter ecosystems, such as flooded grasslands, mangroves, and deserts, will need to move much more rapidly to stay in their comfort zone - sometimes more than a kilometer per year. This is especially crucial for plant species, which due to their being rooted in the ground cannot migrate at nearly the pace of animals in response to habitat changes.

Mangrove ecosystems will also need to move rapidly to stay in their comfort zone.

Climate change will be felt most swiftly by inhabitants of largely flat landscapes, such as mangroves and prairie grasslands, where the rate of warming may more than double the quarter mile per year average calculated for ecosystems generally, the study found.

Nearly a third of the habitats studied in the report face climate change rates higher than even the most optimistic plant migration estimates.

Lowland deserts are likewise subject to a higher velocity of climate change, although the trend toward protecting large swaths of desert may ease the problem there.

By contrast, much of the world's forest habitats and grasslands already have been severely fragmented by development, making mitigation of climate change in those landscapes harder and leaving their species more vulnerable.

The study suggests that scientists and governments should update habitat conservation strategies that have long emphasized drawing boundaries around environmentally sensitive areas and restricting development within those borders.

A more "dynamic" focus should be placed on establishing wildlife corridors and pathways linking fragmented habitats, said Hamilton.

"One of the most powerful aspects of this data is that it allows us to evaluate how our current protected area network will perform as we attempt to conserve biodiversity in the face of global climate change," says Healy Hamilton, Director of the Center for Applied Biodiversity Informatics at the California Academy of Sciences.


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