there’s a virtual “climate crystal ball” just a few miles from washington d.c. in edgewater, md, where the nation’s longest-running carbon dioxide experiment is still going strong. smithsonian scientists are using a chesapeake bay salt marsh to get a glimpse of what plant life will look like at the end of the century if atmospheric co2 levels continue to rise.

energynow! chief correspondent tyler suiters looks at how the smithsonian environmental research center is duplicating the effects of rising co2 levels on a small-scale, then forecasting what it means for plant ecosystems. he interviews patrick megonigal, a biogeochemist at the center and gary peresta, an environmental engineer. they give him a tour of the center and a look at how the research — and the researchers themselves — have evolved over the past two decades.