An aerial view of a section of the Grand Canyon in Arizona on July 7, 2025. (Daniel Slim/AFP/Getty Images)

This edition of Vivien’s Summer Climate Road Trip is a big one, some might say the grandest one…

That’s right, today we dive into how the world’s most famous canyon is impacted by climate change. One of the Seven Natural Wonders of the World, the Grand Canyon draws around 4.5 million visitors every year and was the 4th most visited national park in 2025. It was established by President Theodore Roosevelt in 1919 and has been designated a World Heritage site.

The Grand Canyon first formed when the Colorado River began carving it out more than 5 million years ago. The river is 1,450 miles long, making it the 6th longest river in the United States. Besides the 277 miles that run through the Grand Canyon, the Colorado also passes through seven states, two nations, and 11 state parks and monuments.

The Colorado River flows by the historic Navajo Bridge on June 23, 2021 in Marble Canyon, Arizona. Below average water flow is expected in the Colorado River due to severe drought. (Justin Sullivan/Getty Images)

But the Colorado is shrinking thanks to an extended drought that started in the year 2000. Climate change has accelerated evaporation from reservoirs and is melting snowpack faster, so the rivers that feed the Colorado dry up earlier in the season. This historically long drought has reduced the Colorado River system storage to about 36% capacity.

Lake Mead and Lake Powell are connected by the Colorado river through the Grand Canyon, they are the largest two reservoirs in the country and have hit historically low water levels. This is a huge issue for the roughly 40 million people from Denver to Los Angeles that rely on the river for most of their water needs.

Visitors can raft through the Colorado River in the Grand Canyon, but there is a lottery system every year to determine the 30,000 people who get to go. There are concerns, however, that water levels will soon get too low for rafting the full length of the river. According to the National Park Service, rafting generates about $46 million annually and serves 22,000 tourists.

Visitors ascending the South Keibab Trail with mules take a break at the South Rim of the Grand Canyon National Park in Arizona on July 13, 2014. (Sean Gallup/Getty Images)

There is another lottery for mule rides where you can ride around the south rim in style! A fair warning, though, that these fill up early and can be booked up to 15 months in advance.

You can also take helicopter tours, but that has proved to be controversial, sparking debate over noise pollution for the rest of the canyon-goers, who say the helicopter noise disrupts them trying to soak in the natural environment.

There’s also a climate impact on vegetation and wildlife here. For example, the number of mountain lions — also called cougars — has been dwindling due to species migration and temperature changes. This may sound like a relief if you’re visiting, but these mountain lions are incredibly important predators for the food web in the Grand Canyon region. In fact, you’re more likely to hit one with your car than for it to attack you, and the Park Service advises people to use caution while driving and be on the lookout for mountain lions and other animals.

Hualapai dancers perform at the opening ceremonies for the Skywalk on the western rim of the Grand Canyon on March 20, 2007, on the Hualapai Reservation in Arizona. The Hualapai are one of 11 tribes that have historic connections to Grand Canyon National Park. (David McNew/Getty Images)

There are 11 Tribal communities currently living in the Grand Canyon region. The National Park Service works with these indigenous communities and hosts cultural demonstrations, Native American Artisans Vendor Markets and a new Tribal-run welcome center called the Inter-Tribal Cultural Heritage Site — the first of its kind in the National Parks.

In 2023 the Biden Administration established Baaj Nwaavjo I’tah Kukveni — Ancestral Footprints of the Grand Canyon National Monument. This monument preserves almost a million acres of land adjacent to the Grand Canyon. The proclamation that established it also stresses the importance of incorporating generations of wisdom and knowledge from native tribes into modern day conservation and sustainability efforts.

Vehicles wait in line at an entrance to the Grand Canyon National Park on February 23, 2025. (Brandon Bell/Getty Images)

The Grand Canyon National Park has been given the highest level of protection under the Clean Air Act. Despite this, there is pollution from coal-burning power plants nearby, causing haze. On days with poorer air quality, visibility is also impacted, causing the scenic views that make the canyon grand to be a little less impressive. This has been a point of concern since the 1970s with environmentalists wanting to preserve the Grand Canyon’s air quality.

Want to dive deeper? Check out Bill Weir’s episode of The Wonder List on the Colorado River.

The moon completely covers the sun during a total solar eclipse as seen from Arija, Spain, August 12, 2026. (Borja Suarez/Reuters)