Earth Notes: Wupatki's Blowhole

Feb 17, 2021

Blowholes are commonly associated with ocean coastlines, but they exist in the desert too. One of the most well-known of these is at Wupatki Pueblo near Flagstaff.

File image: The blowhole at Wupatki National Monument
Credit nps.gov

Blowholes are essentially small openings in the earth where air blows out or gets sucked in, acting as a natural fan of sorts. Researchers in northern Arizona believe the Wupatki blowhole is connected to an extensive underground system of fractures.

It measures a few inches across and has been enclosed in a masonry box so visitors can lean over for a blast of cold air on a hot summer day.

Temperature and atmospheric pressure determine the direction of airflow through the day. When it’s warmer and outside pressure is lower than inside the blowhole, air flows out – sometimes up to 30mph. The reverse happens when it’s colder outside and air pressure is higher. The heavier, denser air is pulled in.

In the early 1960’s, researchers with the Rand Corporation studied several blowholes in the Wupatki area. They sent chemical tracers into the cracks, some of which showed up at other blowholes 25 miles away.

Blowholes are often associated with archaeological sites. The one at Wupatki Pueblo is beside a spacious ball court believed to have been built by Indigenous people of the area hundreds of years ago for playing ceremonial games. The Hopi, Zuni, Navajo and Southern Paiute all have traditional names for this desert blowhole. All refer to the wind.