Death Valley’s ‘world’s hottest temperature’ record may be due to a human error
Death Valley has held the record for the hottest air temperature ever measured near the Earth’s surface for 112 years, but scientists are now calling for the title to be revoked.
According to U.S. Weather Bureau data, the air temperature at Greenland Ranch in Death Valley reached 134 degrees Fahrenheit (56.7 degrees Celsius) on July 10, 1913. This is still the highest air temperature ever recorded, but its authenticity has been debated by meteorologists and climatologists, because – despite global warming — temperatures in the region have rarely reached 130 F (54.4 C) since 1913.
For the study, Spencer and his colleagues analyzed July temperatures recorded at stations within 150 miles of Greenland Ranch between 1923 and 2024. The stations were between 3,000 and 3,700 feet (910 to 1,130 meters) above sea level, while Greenland Ranch is 178 feet (54 m) below sea level. adjusted the data based on altitude. (These were the closest stations to the ranch and provided the most reliable long-term data.) The team then compared the values and looked at high-elevation July temperatures from 1913 to estimate the temperature at Greenland Ranch that day.
They found that the air temperature at Greenland Ranch on July 10, 1913, was about 120 F (48.9 C), far from 134 F. “The unusually warm temperatures measured at Greenland Ranch in early July 1913 were found to be inconsistent with temperatures at surrounding stations,” they wrote in the study published September 24 in the journal. Bulletin of the American Meteorological Society.
Many scientists were previously skeptical on the Death Valley temperature record, but little I really questioned it because the World Meteorological Organization (WMO) accepted it and observations from the early 1900s to examine the Greenland Ranch data were rare, Spencer said.
“All deserts are hot in the summer, but Death Valley is particularly hot because it is below sea level,” he said. “The Death Valley record has more entertainment value than climatological value, with an element of ‘bragging rights’ from a tourism perspective.”
The U.S. Weather Bureau set up a station to measure temperatures at Greenland Ranch in 1911. The shelter was initially placed on the edge of an irrigated alfalfa field, but later photographs suggest that the ranch’s foreman, Oscar Denton, moved it to a warmer site above bare ground without official approval or documentation, according to the study.
Denton may have done this because ranch workers were accustomed to measuring warmer temperatures on the ranch veranda than recorded by the station and he wanted their experience reflected in the data, the researchers wrote. The veranda had a double roof, which could vent hot air onto the veranda, they noted.
“Although the station’s distance from the irrigated field does not explain the excessively warm temperature measurements, particularly those of the first two weeks of July 1913, they confirm a tendency to deviate from proper observation protocol,” they wrote.
Denton may also have replaced some of the station’s readings with the readings from the thermometer on the veranda, Spencer said. “Newspapers, magazines, books and even correspondence with the San Francisco Weather Bureau at the time show that higher temperatures of 135 degrees were obtained from this veranda using one or more thermometers of unknown origin,” he said.
Results suggest Death Valley’s world record should be overturned, even if temperatures of 130 F recorded in 2020 And 2021 could help the valley preserve it, Spencer said. The period from July 2 to 18, 1913 and other recorded years also show abnormally high temperatures that should be scrutinized, the researchers noted in the study.
“I would support further investigation of this by WMO and NOAA’s National Center for Environmental Information,” said Dan McEvoyassociate research professor of climatology at the Desert Research Institute who was not involved in the study.
The true story behind the value recorded on July 10, 1913, may never be known, but the study’s conclusion that 134 F is incorrect is compelling and based on solid historical evidence, McEvoy told Live Science in an email.
“They sample from many surrounding stations, not just picking one place,” he said.
