Why is Death Valley so hot?

The Science of National Parks

View from Golden Canyon Trail head in Death Valley

As an engineering student, relocation every 8 months has been part of the college experience. As a result of my internships being all over the country, I had to complete my 3rd cross United States drive this month and this time I wanted to make it a little more fun by visiting 8 national parks and diving into the science behind them. Now back home, I want to share that science with you all!

Driving from Santa Rosa, CA to Gainesville, FL my first stop was Death Valley National Park, the hottest and driest place in the United States. I experienced 113 degrees Fahrenheit weather with a painfully hot wind, but temperatures can reach up to 134 degree Fahrenheit (57 degrees Celsius). The record 134 degrees is the hottest temperature ever recorded on Earth and was recorded back in 1913 in Furnace Creek. So what lets this intense heat occur?

Death Valley’s crazy heats are caused by a combination of the lack of water, geography, and materials that make up the valley.

The average yearly rainfall in Death Valley is only 2 inches. This is less than many other deserts in the world, averaging around 10 inches of rain annually. This intense lack of water also creates a lack of plants in the area resulting in the expanses of sand in the valley open to constant heating by the sun.

Sea level in Death Valley

Driving into the valley you get to experience the geography of the environment, traveling from 1000 feet to 4000 feet above sea level and down to 100 feet below sea level. These mountain ranges you drive over top 4000 feet and surround the lowest point in the United States of 282 feet below sea level. This creates an interesting phenomenon of trapping the hot air within the valley.

Sand and rocks make up the valley floor which radiate a large amount of heat. However, because of the geography, this hot air cannot escape. Instead, the hot air rises along the valley walls, cools slightly and then falls back to the valley floor to be heated even more by the hot sand and low elevation air pressure. This concept of movement by heating and cooling is called convection and exists in many other life circumstances like the boiling of water or in a kitchen oven. Despite the movement of air and possibility of high winds, the winds do not do much to cool down the hikers in the valley because the wind is still very hot.

The heat can be so extreme that signs in the park advise turning off the air conditioning in certain areas to avoid overheating of cars, making the experience an even toastier one. Additionally, hiking is recommended only before 10am and with lots of water.

Despite the heat it is worth braving the heat to experience the truly unique views of Death Valley. This unique environment allows for rock formations, salt flats and expanses unlike anything else in the United States.

Want to learn more about Death Valley and the national parks? Visit their website here!

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Drive through Death Valley