Stephen Jackson, NPR, Christopher Joyce Npr discussed on All Things Considered
Climate scientists are struggling to figure out how a. Warming planet will affect different ecosystems like forests swamps grasslands so researchers looked back at the end of the last ice age to see, what might, be in store for us as NPR's Christopher Joyce reports. They suspect some ecosystems could change completely in a century, much of the northern. Hemisphere was covered by ice sheets twenty thousand years ago then. The earth started warming up by ten thousand years ago. It was warmer by about seven to. Twelve. Degrees Fahrenheit Ecologists. Stephen Jackson, says that makes that period of history much like what greenhouse gases are doing to the earth now the change, over, the next, one hundred hundred fifty years is of similar magnitude. Globally to what we, saw during the last ice retreat Jackson worked for the US Geological Survey he and a team of more than forty. Scientists examined the fossil pollen. And vegetation to figure out how that ancient warming affected various ecosystems the researchers found huge changes after the. Ice age in Jackson's neighborhood in Arizona for example it's now desert cactus and Trump's mostly fifteen thousand years ago though what we'd see, there instead, is juniper Pinon woodland and evergreen woodland utterly different from. The vegetation we'd find here so as climate changes some forests may give way. To Woody shrubs or grassland or grassland could convert to desert. Writing in the journal science the researchers say they can't Predict exactly where and how fast these changes will happen for one. Thing the. Warming now is a lot faster than it was, at the end of the ice age instead of that. Happening, over several thousand years we're cramming all of that climatic change in two century century and a half and their historical record shows a. Climate going from frigid too warm now. It's moving from warm to warmer that may be different but Jackson says one thing is likely more unpredictability maybe even ecosystems that are totally. New and that poses challenges for forests wildlands and even fisheries and for people. Who depend, on them that's gonna create a great deal of chaos ecological chaos out there as they try to adapt and, respond, to those, changes these changes are happening now some forests in. The southwest are dying, and being replaced by smaller plants and shrubs ecologist David Beshir's at the university of Arizona says it's similar to what. Happened in the, past each Changes is very temperature sensitive and I think that's the most important takeaway message because that's what we're dealing with right now I. Think in contemporary times in the journal scientific reports Beshir's and scientists in Australia showed how quickly big changes can happen a. Heatwave in Western Australia. In, twenty eleven caused coral bleaching in the ocean as well as tree deaths damaging insect outbreaks and die-offs of birds all very different ecosystems responding to a warmer environment Christopher Joyce NPR. News You're listening to all, things considered from NPR news is a look at.