These Scientists Tested How Climate Change Affects Wild Meadows—With Alarming Results

Scientists led by Professor John Harte set up a 29-year warming experiment in Colorado's Rocky Mountain meadows in 1991, heating plots 2 degrees Celsius above normal to simulate future climate conditions. Instead of flourishing as once predicted, wildflowers and grasses vanished and were replaced by sage brush and shrubs, which increased 150 percent in the warmed plots, while soil fungi that help plants acquire nutrients declined sharply. A resulting study published in the Proceedings of the National Academy of Sciences warns these meadows will disappear within decades if global warming reaches 2 degrees Celsius above preindustrial levels. The findings signal a broader crisis: alpine grasslands across Europe, the Arctic, and mountains globally are undergoing "shrubification," with tree and shrub species moving uphill as temperatures rise. Researchers caution the ecosystem shift is accelerating faster than climate projections predicted and risks triggering permafrost melting and increased carbon emissions in cold environments worldwide.