Rising Temperatures Put Alpine Wildlife at Risk
If you are hiking in Yosemite's high country, you may spot a pika, the adorable alpine relative of the rabbit that lives on rocky mountaintops and talus slopes. In Grinnell's day, they had the run of the mountains from 7,500 feet elevation and above. Today, scientists can't find them below 9,500 feet. What has prompted an entire species to shift 2,000 feet in just 100 years? Researchers say that warming temperatures are forcing pikas to climb higher in search of alpine conditions. With temperatures projected to increase further, their upward march may continue until their habitat recedes right off of the mountaintops. Other beloved high-country animals could follow in their footsteps.
Mild Winters Endanger World-Renowned Mountain Meadows
Yosemite's broad, expansive Tuolumne Meadows cradle some of the most stunning wildflowers in the American West, with brilliant displays of arrow-shaped shooting stars, bright yellow monkeyflowers, purple meadow paintbrushes and others. Global warming, however, may dull the beauty of this national treasure. Mountain meadows like Tuolumne exist where the combination of heavy snow cover in the winter and a brief growing season in the summer make it impossible for tree seedlings to survive. But the rising temperatures, shrinking snowfalls and longer summers brought on by global warming could allow trees to creep into the meadows, choking out the open range flowers and wildlife depend on. Tuolumne Meadows isn't alone in being at risk; countless other meadows throughout Yosemite could also disappear in a forest of trees.
Hotter Weather Prompts More Overcrowding in the Park
Many visitors to Yosemite know the frustration of sitting in RV-clogged traffic or waiting in line to climb a rock wall. It's no wonder, considering more than 3 million people visit the park each year. Thanks to higher temperatures, more people are likely to seek refuge in cool mountain parks. Yosemite, sitting in the nation's most populous state, is most at risk. A recent study found that, faced with global warming, people likely will come to a mountain national park more often and stay longer. Overcrowding would also aggravate one of the most serious current problems in the national park system: a shortage of funds to meet the needs of the people who visit the parks now.
Warming Accelerates the Melting of Yosemite's Glaciers
The handiwork of glaciers is visible across Yosemite's unique landscape, from towering rocky spires to granite domes worked smooth over millennia. With global warming putting the heat on Yosemite's glaciers, however, the glaciers themselves could disappear. Scientists studied six glaciers in Yosemite and found that the glaciers had decreased in area from 31 percent to 78 percent in the last century. Lyell Glacier, Yosemite's largest, has lost 35 percent of its west lobe and 70 percent of its east lobe, with much of the loss occurring since 1944.
Changing Climate Leads to Dirtier Air
Californians come to Yosemite to escape thick smog, but in the future, they may find the air pollution that they thought they left at home. High temperatures fuel the production of ozone -- a potent form of smog. The pollutants that create ozone come mainly from sources far from the park, but they can travel long distances. Yosemite already has an ozone problem, with levels high enough to cause health problems for visitors. Hotter temperatures brought on by global warming will most likely make Yosemite's air even more polluted.
