Changing Climate Will Make Massive Shifts in Earth's Vegetation [NASA study]

Scientific American Magazine/ By Lauren Morello and ClimateWire

Climate change will alter the mix of vegetation on 49 percent of Earth's land surface by the end of this century, scrambling and shifting existing ecosystems, according to a new study.

Researchers at NASA and the California Institute of Technology say the changing climate will also convert 37 percent of the world's land ecosystems from one type -- such as tundra, forest or grassland -- into another by 2100.

Those vegetation shifts are likely to affect animals and insects that have evolved to live among particular plant species and within certain temperature and precipitation ranges, said the study's lead author, independent scientist Jon Bergengren.

"Animals that are dependent on plants will either have to migrate with the plants, if the plants can successfully migrate, or hang on with plants that are struggling to survive," said Bergengren, who conducted the research as a postdoctoral fellow at Caltech's Jet Propulsion Laboratory. "Either way, there are problems."

Bergengren said that widespread human development will complicate and in some cases prevent plants and animals from migrating to new habitats as climate change alters existing ecosystems.

"A lot of times, when a plant or animal wants to migrate, it runs into a monoculture agricultural zone, or it runs into a city," he said.

The study, published by the journal Climatic Change, is based on the output of a computer model of vegetation change. Researchers used the model to project how the world's vegetation would shift over the next three centuries under the "middle of the road" greenhouse gas emissions scenario developed by the Intergovernmental Panel on Climate Change. It assumes the world's greenhouse gas emissions will double by 2100, then stabilize.

Northern forests move into the tundra.   More >>