Tourists have their pictures taken next to the famous thermometer in Furnace Creek, in Death Valley in the United States, one of the most hostile places on the planet. - Richard Brian / AP / SIPA

  • The temperature climbed Sunday to 54.4 ° C in Death Valley in the United States, according to the US meteorological service, one of the highest values ​​ever measured.
  • When a station measures an extreme temperature, a whole verification process takes place.
  • It is up to the World Meteorological Organization, which depends on the UN, to certify these records.

It was very, very hot in Death Valley in the United States. The mercury reached 54.4 degrees Celsius, a value close to the world record. But how and by whom are these records validated? Know that there is a whole process to check for these extreme temperatures, and that's no joke. Diving into the very rigorous organization of world meteorology.

Incredible 54.4 ° C (129.9 ° F rounded to 130 ° F) at Furnace Creek #DeathValley (USA) this 08-16-2020.
* If the measurement is correct *, it would be a WORLD RECORD of heat in front of 54 ° C on June 30, 2013 at the same station and 54 in Mitribah (Kuwait) on 07-21-2016 (corrected to 53.9 by the WMO) .

- Etienne Kapikian (@EKMeteo) August 17, 2020

How does it work when an extreme temperature is noted in the world?

First step: verification. “When an extreme weather event occurs, we first test the equipment that measured it,” says Dan Berc, meteorologist at the Las Vegas Bureau of Meteorology. The teams on site test the probes and look at the corresponding data to determine if the value is correct, or if it is an anomaly. This work should also be done on the Furnace Creek thermometer in Death Valley "as soon as possible", confirmed the meteorologist.

If the equipment is deemed functional, then “a climatic extremes committee is convened to validate the observation. If it is deemed to be compliant, this temperature will become a given ”. This process can take several months. After this homologation, the record, if it is one, must be validated by a higher body: the World Meteorological Organization (WMO). This body, which depends on the UN, serves as a reference around the world on issues of weather, climate and water.

The WMO rapporteur on weather and climate extremes, Randall Cerveny, has already made a statement about the possible record measured in Death Valley: “Everything I have seen so far indicates that this is a legitimate observation. I recommend that WMO accept this observation on a preliminary basis. In the coming weeks we will of course be reviewing it in detail, working with the US National Committee on Climate Extremes, using one of our international assessment teams. "

Tourists roam America's stifling Death Valley in 2018. - Brian Melley / AP / SIPA

Where was the heat world record measured?

The world record was measured on July 10, 1913… in Death Valley, already one of the most hostile places on the planet. A weather station recorded what remains officially the highest temperature ever measured on Earth: 56.7 ° C. This was followed by the 55 ° C recorded in Kebili, Tunisia, in 1931. In 2016 and 2017, 54 ° C was reached in two places, in Kuwait and in Pakistan.

For the anecdote, the WMO also records the records of multiple events: low temperatures (-89.2 ° C in Vostok in Antarctica in 1983), precipitation (3.93 meters of water fell in 72 hours in the Commerson crater of La Réunion in 2007), the heaviest hailstone (1.02 kg, Bangladesh, 1986) or even the longest lightning: 16 seconds in Argentina in March 2019.

Why is this important?

In a time when climate change has become a major problem, scientists want to rely on solid data. "As meteorological data is used more and more as indicators of climate change / and an increasingly extreme climate, the approval of new weather records should be recognized as a top priority in the global meteorological community", recalls the OMM on its site.

Do errors exist?

If today all these records are closely examined by weather experts, in the past, records were not approved. Thus, for decades, the world heat record officially dated from 1922 in El Azizia, in modern Libya: 58 ° C. But a panel of experts from the World Meteorological Organization had investigated in detail from 2010 to 2012 this planetary record, before concluding that the reading was undoubtedly overestimated by 7 degrees, due to problematic devices and an observer. inexperienced.

The world record of 1913 could in theory also be wiped off the shelves: in 2016, two American experts, William Reid and Christopher Burt, published a long analysis concluding in an error; but no official investigation is underway.


38 ° C… A new heat record in Siberia which extends a list of worrying signals


June 2019 breaks heat record around the world

  • Society
  • Science
  • Weather forecast
  • Temperature