The barrier islands at Cape Hatteras National Seashore are in danger of disappearing as rising sea levels threaten to make the seashore, which draws millions of visitors a year, an underwater attraction. The shore’s Cape Hatteras Lighthouse, the tallest brick lighthouse in the United States has already been moved 2,900 feet inland because of sea level rise, and the National Park Service fears that in the face of rising seas and stronger storms, another move will come sooner rather than later.
With thermometers rising globally, heat itself will become a real problem in areas that are notorious for their already high temperatures. Being outdoors may prove to be unbearable for many visitors to national parks, especially Death Valley National Park, known as the hottest place on earth. In the park, average high temperatures already reach a blistering 99°F in May, 109°F in June, 115°F in July, 113°F in August, and 106°F in September. With the park’s record high temperature at 134°F, and known global warming trends, expect the scorching season to get longer. Expect the same at Zion, Arches, Joshua Tree and Lake Mead National Recreation Area.
Everglades National Park is suffering tremendous sea level rises, serious enough to submerge the unique plant habitats that hold the park in balance, including buttonwood forests, mangrove swamps and endemic orchids and herbs. The low elevation of the Everglades makes this park particularly vulnerable, as studies suggest that a sea level rise of six feet will submerge virtually all of the park, which includes the largest freshwater sawgrass prairie in North America, the largest protected mangrove ecosystem in the Western Hemisphere, and a wide variety of rare and endangered species. As little as two feet of sea level rise will radically alter the ecosystem with an influx of salt water.
Glacier National Park’s namesake glaciers have been rapidly melting and may be gone by 2030. Out of approximately 150 glaciers present in 1850, only about 25 remain large enough (at least 25 acres in area) to be considered functional glaciers today. According to reports from the National Park Service, glacier recession models predict that in less than two decades, Glacier National Park will be without glaciers. This estimate may occur even earlier, however, as glaciers are retreating faster than their predicted rates.
Populations of trout, a cold-water fish, may plummet as a warming planet raises water temperatures. Grand Teton National Park has a worldwide reputation for its excellent trout fishing, as one of the only places to catch fine-spotted cutthroat trout. But with recent projections, fishing in the park may become restricted. That means a potential end to fly-fishing on the Snake River, a popular activity among tourists to the park.
A hotter climate is projected to worsen concentrations of ground-level ozone, an air pollutant serious enough to cause respiratory problems in some people, according to the U.S. Environmental Protection Agency. In Great Smoky Mountains National Park, ground-level ozone levels are chronically high (up to two times higher than in nearby cities), and have visibly affected sassafras and cutleaf coneflower plants, as well as forest trees. In addition, about 90 percent of black cherry trees and milkweed plants throughout the park are showing signs of ozone damage, such as reddening on plant leaves.
A combination of higher temperatures and decreased moisture threaten to eliminate the iconic joshua trees in Joshua Tree National Park. If the Joshua trees go, the entire ecosystem will suffer, as animals such as the desert wood rat, blacktail jack rabbit and antelope ground squirrel, who find moisture by gnawing through the bark of live trees, with perish in extreme drought. Without its signature trees, the park would lose its unique character, and as one tourist told NPR, “It would not be Joshua Tree any longer. It would just be space.”
As the climate changes, moderate rain has turned into frequent and intense downpours that have increased the likelihood of flooding, especially in Mount Rainier National Park, where 18 inches of rain fell in 36 hours in November 2006. The debris flows and floods from the storm destroyed trails, damaged campgrounds, and severed power lines, causing the park to close for six months, a time when about 170,000 people normally would have visited. According to the Park Service, the heavy rainfall “changed the landscape of the park forever.”
With visitors flocking to cooler national parks to escape the oppressive heat, northern and mountain parks run the risk of overcrowding. In Rocky Mountain National Park, surveys suggest that as soon as 2020, the number of visitors expected to arrive could increase the number of visitor days by more than one million a year—nearly a one third increase.
A mountain wildland that's home to bears, wolves and herds of bison and elk, Yellowstone National Park has an ecosystem in peril—especially for its grizzly population. The mountain pine beetle, which is spreading further into Yellowstone thanks to a longer warm season, is killing off the whitebark pine, a major source of food for grizzlies. The bears depend on the large and nutrient-rich seeds of this tree, but with a dwindling supply, grizzly bears will suffer a lower survival rate and lower birth rates if pregnant females lack enough fat entering hibernation.
A changed climate is destined to reduce water availability, with particular vulnerability to the Colorado Plateau, which is expected to become hotter and drier. The North Fork of the Virgin River, which carved the spectacular Zion Canyon, is drying up. Because this section of river is undammed, it depends on natural precipitation to maintain its flow—precipitation that's expected to drop significantly in coming decades. Zion's piñon forests are also threatened by reduced rainfall.