Quirks and Quarks

Why are the hottest temperatures measured in Death Valley?

Death Valley is more accessible than the Sahara desert which makes recording temperature much easier.

Death Valley is more accessible than the Sahara desert which makes recording temperature much easier.

Furnace Creek in Death Valley, California reached a record temperature of 54.4 C on August 16th, 2020. (NPS/J. Jurado)

This week's Question comes from Paul Timmins in Huntsville, Ontario. He asks: 

Why does Death Valley have the highest temperatures ever recorded on earth versus some place like the Sahara or somewhere near the equator?

Rachel White, an assistant professor in the Department of Earth, Ocean and Atmospheric Sciences at the University of British Columbia explains that places on or near the equator would have the highest average temperatures over a full year. However, because they have weak seasons, there is less chance of extreme temperatures in summer.

Places on or near the Tropic of Cancer in the northern hemisphere or the Tropic of Capricorn in the southern hemisphere, where the Sun is overhead at the solstices, have hotter summers than places on or near the equator. They also have colder winters.

The Sahara Desert falls within this region, yet Death Valley, California still records higher temperatures. The explanation is simple. Throughout the Sahara desert, especially the very hot areas, it is difficult to go there to record temperatures or even maintain an automotive weather station.

Regardless, recent satellite data suggests that the hottest place on Earth may in fact be The Dasht-e-Lut Desert in Iran, nearer to the Tropic of Cancer. Scientists recently travelled there to verify the satellite data and recorded a temperature of 61 degrees C. That is more than five degrees hotter than the high temperature of 54.4 C recorded in Death Valley this past August. 

Hikers brave the extreme heat in Golden Canyon, Death Valley, California (NPS Kurt Moses)