Warming Will Create Micro-Climates, Scientists Say
MELISSA BLOCK, host:
From NPR News, this is ALL THINGS CONSIDERED. I'm Melissa Block.
ROBERT SIEGEL, host:
And I'm Robert Siegel.
Scientists who study climate are pretty sure that 100 years from now things are going to be warmer. But that won't necessarily mean the same thing in the Rocky Mountains as it will in the Amazon. Each local climate will respond differently, so will the animals and plants that live in those places.
NPR's Christopher Joyce talked to scientists who say this could mean that in the 100 years the Earth will have some totally new kinds of climates.
CHRISTOPHER JOYCE: The ultimate multi-taskers are ecologists. They look at a forest or a desert and they track rainfall patterns, or air and soil temperatures, what plants grow there and who eats what. It's like juggling a dozen balls at once.
Now ecologists have to factor in climate change. How will it affect local climates - the sum of temperature, rainfall, and everything else that makes up the local weather. What will happen in the Rockies or the Florida Everglades? Well, Stephen Jackson, a botanist and climate scientist at the University of Wyoming, says one thing that will happen is there will be some totally new climates.
Professor STEPHEN JACKSON (Botany, University of Wyoming): I think it like a "Twilight Zone" world, where a lot of what's familiar to us will disappear and climates that are completely unfamiliar to us will appear.
JOYCE: Remember, for example, the dioramas in a dinosaur museum - weird plants and animals we don't see anymore. Climates were different in the distant past and now these scientists say new ones are emerging.
Prof. JACKSON: It's certainly been at least several million years since we've seen climates quite like these, and it's very possible that the planet's never experienced those kinds of climates ever. And those climates will of course not only be new to humans, they'll be new to ecological communities - communities of plants, animals, microbes and so forth.
JOYCE: Jackson and a team of scientists have used computer models to predict how different some of the future climates will be. Two things, they say, will happen - some climates will just disappear. John Williams is a geographer at the University of Wisconsin.
Professor JOHN WILLIAMS (Geography, University of Wisconsin): Our analyses suggests at places such as regions around the Arctic or high elevation regions such as the Peruvian Andes or the East African Highlands such as Mt. Kilimanjaro and Mt. Kenya, these are areas that are at the cold end of the current range of our global climates are the ones that disappear.
JOYCE: And new climates will appear in new places. Take a mountain, for example. Williams explains that climate zones are stacked up the slope like layers of a cake.
Prof. WILLIAMS: You might start off in grasslands and then you'd move to some (unintelligible) woodland or shrubland, maybe a juniper woodland. And then move up into Ponderosa pines, then in upper elevations spruce and fir forest, and then finally to some sort of alpine tundra up at the top.
JOYCE: A warming climate will push each of these zones upwards, along with all the plants and animals that live in them, except it won't be that neat and tidy.
Prof. WILLIAMS: Different species would move at different rates up the side of the mountain, so we would get some reshuffling of these species. So you get both the possibility of having new zones along that side of the mountain and then of course for the species at the top of the mountain, there's no place for them to go.
JOYCE: Williams and his colleagues report their work in today's issue of the proceedings of the National Academy of Scientists. They can't say how many current climates will disappear or how many new ones will emerge, though they think it will be a lot. Most of the disappearances will be in colder regions and most new ones will pop up in tropical areas.
Now, it's true that climates have been changing throughout Earth's history, but climate scientist Jonathan Overpeck at the University of Arizona at Tucson says this time the change will be fundamentally different from anything that's come before.
Dr. JONATHAN OVERPECK (Geosciences, University of Arizona): It's going to come a rate much faster than plants and animals on Earth have ever seen in the time they've been on Earth. And that's at the same time that we're going to be hitting them with a lot of other challenges besides climate change - pollution and land use change, deforestation and fragmenting of the landscape.
JOYCE: Overpeck says these new climates will not only emerge faster but they'll be hard to predict. Some places will be rainier, others drier, or windier or sunnier, and the plants and animals will respond in unpredictable ways.
Dr. OVERPECK: It's kind of scary in the sense that it'll be very hard to manage the response of this change because we really don't know in any one location exactly how climate's going to change, particularly with rainfall.
JOYCE: At this point, these scientists say, all that they could be sure of is that the climates our grandchildren will experience are going to be rather different from ours.
Christopher Joyce, NPR News.