Death Valley National Park is located in Eastern California. During the summer it is one of the hottest places on Earth where the highest recorded temperature of it reached 54.4°C or 130F.However, whenever the hottest temperature gets updated a historical artifact claiming that the hottest temperature it reached is actually 57°C or 134F. This was assessed and is claimed as an observer error.

Death Valley National Park

The Automated Surface Observing Systems (asos) is what we use to collect data of temperatures, precipitation, cloud cover, wind speed, and pressure.We have been using the asos since the mid-90s and on average these send data reports every 20 minutes.Official weather-taking themometers are different from the ones that people install in their houses. These official thermometers need to be shielded from external factors that can influence the temperature outcome.

How We Record Temperatures

Our systems for measuring temperature are more accurate now with all the automated readings and less of the "to decipher" handwritten records. Although there is still a chance for an anomaly to occur, it's pretty rare.What happens now is that due to the temperatures rising worldwide and with the data we have, we cannot and should not ignore the wrath of intensified weather.

Why Temperatures Matter

<img src="https://img.connatix.com/b9979545-b5b2-4ef1-a527-a877cdc17c6e/dc0779c6-a67d-4eca-9fc3-df27dfa107e2.jpg?crop=600:338,smart&amp;width=600&amp;height=338&amp;format=jpeg&amp;quality=60&amp;fit=crop" alt="The Best PS5 games to show off the console’s next-gen features" width="600" height="338">Some records are a little trickier to define than others, though. Take Death Valley in California as an example. This is the hottest, driest, and lowest national park in the US and is no stranger to intense heat. High temperature averages are 100 degrees Fahrenheit and above for at least a third of the year, and just last week produced the highest daily average temperature observed on the planet <a href="https://www.washingtonpost.com/weather/2021/07/12/death-valley-record-heat-earth/" rel="noreferrer noopener" dir="ltr">at 118.1 degrees</a>. On Friday, July 9, the high temperature reached a scorching 130 degrees Fahrenheit, one of the highest recorded temperatures of all time.But every time Death Valley has a wildly high temperature, a weird historical artifact pops up—the one time in 1913 that the temperature <a href="https://www.nbclosangeles.com/weather-news/death-valley-world-record-temperature-heat/2394047/" rel="noreferrer noopener" dir="ltr">was recorded as 134 degrees Fahrenheit</a>. Over a century ago, US Weather Bureau observer Oscar Denton measured a week-long string of <a href="https://www.wunderground.com/blog/weatherhistorian/an-investigation-of-death-valleys-134f-world-temperature-record.html" rel="noreferrer noopener" dir="ltr">suspiciously high temperatures</a> in Death Valley’s Greenland Ranch. If you look at the other temperatures recorded nearby, <a href="https://www.washingtonpost.com/news/capital-weather-gang/wp/2016/10/25/new-analysis-shreds-claim-that-death-valley-recorded-earths-hottest-temperature-in-1913/" rel="noreferrer noopener" dir="ltr">this recording stood out like a sore thumb</a>—temperatures creeping into the high 120’s didn’t start reappearing until the late 1990s when the IPCC had <a href="https://www.newscientist.com/article/dn9912-timeline-climate-change/" rel="noreferrer noopener" dir="ltr">begun to recognize global warming</a>.&nbsp;While that reading is still technically listed as the world’s hottest temperature ever recorded, some argue that this month’s high is likely a more realistic record.&nbsp;“If Friday’s observation passes an investigation (instrument calibration, etc.) then, yes, this is a new reliably measured global extreme heat record,” weather records expert Christopher Burt told <a href="https://yaleclimateconnections.org/2021/07/death-valley-california-breaks-the-all-time-world-heat-record-for-the-second-year-in-a-row/" rel="noreferrer noopener" dir="ltr">Yale Climate Connections</a>. That’s because it was shockingly tricky to get accurate temperature readings in the past, which makes it difficult to know which temperatures are legitimate and which aren’t.<h2>How we record temperatures</h2>Like many modern-day data capturing methods, temperatures (as well as precipitation, cloud cover, wind speed and pressure) have been collected automatically in <a href="https://www.ncei.noaa.gov/products/automated-surface-weather-observing-systems" rel="noreferrer noopener" dir="ltr">Automated Surface Observing Systems</a> since the mid-90s, explains Jon Erdman, a senior meteorologist at the Weather Channel. There are over 900 of these systems throughout the US, and on average report weather data around every 20 minutes.&nbsp;But the thermometer that records temperatures all day every day from stations around the world isn’t exactly like the ones you might have outside your house, Erdman adds. Official weather-taking thermometers need to be shielded from the sun and wind, and have what looks like little lampshades on them so that they can measure the actual surface temperature without being influenced by other sources.&nbsp;“If you don’t shield the thermometer from direct sunlight, it’s going to heat up more,” he says. So if you’re ever wondering why your personal thermometer might show a bit more heat than the Weather Channel is showing, that could be a reason why.&nbsp;Scientists have been shielding their thermometers since the late 1800s, starting with the Stevenson screen, which looked a bit like a <a href="https://www.weatheronline.co.uk/reports/wxfacts/The-Stevenson-Screen.htm" rel="noreferrer noopener" dir="ltr">little white birdhouse or cabinet and held a variety of weather-investigating </a>tools. Like today’s setup, this contraption protected the thermometer from the elements to just get surface temperature.In the 21st century, the setup hasn’t changed much—the key difference is just how involved humans used to be. “What you’ll see in these [historical] measurements is literally hand-written measures of every single day, going and seeing what that thermometer says,” says Karen McKinnon, a professor of statistics and sustainability at UCLA.So, occasional errors are completely within expectation. But how could a person record such a high temperature by accident? From a technological standpoint, in a place as toasty as Death Valley, even a little bit of direct sunlight or scorching hot sand brushing against the meter could rack up some extra degrees, Erdman says.&nbsp;McKinnon has also found<a href="https://dash.harvard.edu/handle/1/32097099" rel="noreferrer noopener" dir="ltr"> in her research that people often round up to preferentially</a> chosen numbers rather than be uncertain about the exact temperature. Then, when it comes to the Global Historical Climate Network Daily database, everything gets rounded up to the closest 0.1 degree Celsius, despite the level of precision it was initially recorded. In her findings, 63 percent of temperature samples were biased by this double-rounding.&nbsp;In a <a href="https://www.wunderground.com/blog/weatherhistorian/an-investigation-of-death-valleys-134f-world-temperature-record.html" rel="noreferrer noopener" dir="ltr">lengthy 2016 take-down </a>of the record, geographer William T. Reid and weather historian Christopher Burt also raised concerns about the observers’ credibility to accurately record temperatures, exaggerating the temperature beyond what anyone could explain meteorologically.&nbsp;“Things can always go wrong,” McKinnon says. “People can misrecord temperatures, which is probably the most likely situation”<h2>Why does any of this matter?</h2>This isn’t the first time a global heat record has been challenged. Back in 2012, a reading of <a href="https://www.eurekalert.org/pub_releases/2012-09/asu-wht091112.php" rel="noreferrer noopener" dir="ltr">136.4 degrees Fahrenheit in El Azizia, Libya on Sept. 13, 1922, was removed</a> from its record-holding spot after an international team found five major concerns with the recording, from unreliable equipment to an inexperienced observer. And there’s certainly a chance that the 1913 Death Valley record could come into reassessment under the <a href="https://www.ncdc.noaa.gov/extremes/ncec/," rel="noreferrer noopener" dir="ltr">National Climate Extremes Committee</a>.&nbsp;And even though our systems are much more accurate nowadays, with automated readings and no deciphering of hand-written notes, there’s still a chance that our modern systems may mess up. “You can certainly have problems at individual sites,” Erdman says, “But those are pretty rare.” Just take some of <a href="https://www.baynews9.com/fl/tampa/weather/2018/10/05/weather-blog--tampa--record-highs--caused-by-sensor-error" rel="noreferrer noopener" dir="ltr">Tampa’s 2018 record highs that ended up being inaccurate</a> due to being too closely located to toasty parking lots and highways, picking up too-high temperatures.&nbsp;Just like every anomaly, there’s a chance that the old record was truly a one-in-a-million occurrence. But whether it stands or not, what really matters is that these records are being broken more and more often in a pattern, we cannot ignore—temperatures are rising worldwide, and the entire planet is now experiencing the wrath of intensified weather.&nbsp;“What you’re gonna see is that there’s an upward trend,” McKinnon says. “And you can see breaking records with a greater probability.”&nbsp;&nbsp;<img src="https://www.popsci.com/uploads/2021/04/16/IMG_7805.jpg?crop=80:80&amp;width=80" width="80" height="80" alt="Sara Kiley Watson">
 <a href="https://www.popsci.com/authors/sara-kiley-watson/" dir="ltr">Sara Kiley Watson</a>is an assistant editor at PopSci. Her work has also been featured in NPR and Business Insider. Contact the author <a title="Contact to Sara Kiley Watson" href="mailto:sarakiley@popsci.com" dir="ltr">here.</a>

In Death Valley and beyond, the quantity of horrifically hot days is what actually matters—not just one blip recorded a century ago.

scienceandnature

Science & Nature

Some records are a little trickier to define than others, though. Take Death Valley in California as an example. This is the hottest, driest, and lowest national park in the US and is no stranger to intense heat. High temperature averages are 100 degrees Fahrenheit and above for at least a third of the year, and just last week produced the highest daily average temperature observed on the planet <a dir="ltr" href="https://www.washingtonpost.com/weather/2021/07/12/death-valley-record-heat-earth/" rel="noreferrer noopener">at 118.1 degrees </a>. On Friday, July 9, the high temperature reached a scorching 130 degrees Fahrenheit, one of the highest recorded temperatures of all time.

But every time Death Valley has a wildly high temperature, a weird historical artifact pops up—the one time in 1913 that the temperature <a dir="ltr" href="https://www.nbclosangeles.com/weather-news/death-valley-world-record-temperature-heat/2394047/" rel="noreferrer noopener">was recorded as 134 degrees Fahrenheit </a>. Over a century ago, US Weather Bureau observer Oscar Denton measured a week-long string of <a dir="ltr" href="https://www.wunderground.com/blog/weatherhistorian/an-investigation-of-death-valleys-134f-world-temperature-record.html" rel="noreferrer noopener">suspiciously high temperatures </a>in Death Valley’s Greenland Ranch. If you look at the other temperatures recorded nearby, <a dir="ltr" href="https://www.washingtonpost.com/news/capital-weather-gang/wp/2016/10/25/new-analysis-shreds-claim-that-death-valley-recorded-earths-hottest-temperature-in-1913/" rel="noreferrer noopener">this recording stood out like a sore thumb </a>—temperatures creeping into the high 120’s didn’t start reappearing until the late 1990s when the IPCC had <a dir="ltr" href="https://www.newscientist.com/article/dn9912-timeline-climate-change/" rel="noreferrer noopener">begun to recognize global warming </a>.

While that reading is still technically listed as the world’s hottest temperature ever recorded, some argue that this month’s high is likely a more realistic record.

“If Friday’s observation passes an investigation (instrument calibration, etc.) then, yes, this is a new reliably measured global extreme heat record,” weather records expert Christopher Burt told <a dir="ltr" href="https://yaleclimateconnections.org/2021/07/death-valley-california-breaks-the-all-time-world-heat-record-for-the-second-year-in-a-row/" rel="noreferrer noopener">Yale Climate Connections </a>. That’s because it was shockingly tricky to get accurate temperature readings in the past, which makes it difficult to know which temperatures are legitimate and which aren’t.

Like many modern-day data capturing methods, temperatures (as well as precipitation, cloud cover, wind speed and pressure) have been collected automatically in <a dir="ltr" href="https://www.ncei.noaa.gov/products/automated-surface-weather-observing-systems" rel="noreferrer noopener">Automated Surface Observing Systems </a>since the mid-90s, explains Jon Erdman, a senior meteorologist at the Weather Channel. There are over 900 of these systems throughout the US, and on average report weather data around every 20 minutes.

But the thermometer that records temperatures all day every day from stations around the world isn’t exactly like the ones you might have outside your house, Erdman adds. Official weather-taking thermometers need to be shielded from the sun and wind, and have what looks like little lampshades on them so that they can measure the actual surface temperature without being influenced by other sources.

“If you don’t shield the thermometer from direct sunlight, it’s going to heat up more,” he says. So if you’re ever wondering why your personal thermometer might show a bit more heat than the Weather Channel is showing, that could be a reason why.

Scientists have been shielding their thermometers since the late 1800s, starting with the Stevenson screen, which looked a bit like a <a dir="ltr" href="https://www.weatheronline.co.uk/reports/wxfacts/The-Stevenson-Screen.htm" rel="noreferrer noopener">little white birdhouse or cabinet and held a variety of weather-investigating </a>tools. Like today’s setup, this contraption protected the thermometer from the elements to just get surface temperature.

In the 21st century, the setup hasn’t changed much—the key difference is just how involved humans used to be. “What you’ll see in these [historical] measurements is literally hand-written measures of every single day, going and seeing what that thermometer says,” says Karen McKinnon, a professor of statistics and sustainability at UCLA.

So, occasional errors are completely within expectation. But how could a person record such a high temperature by accident? From a technological standpoint, in a place as toasty as Death Valley, even a little bit of direct sunlight or scorching hot sand brushing against the meter could rack up some extra degrees, Erdman says.

McKinnon has also found<a dir="ltr" href="https://dash.harvard.edu/handle/1/32097099" rel="noreferrer noopener">in her research that people often round up to preferentially </a>chosen numbers rather than be uncertain about the exact temperature. Then, when it comes to the Global Historical Climate Network Daily database, everything gets rounded up to the closest 0.1 degree Celsius, despite the level of precision it was initially recorded. In her findings, 63 percent of temperature samples were biased by this double-rounding.

In a <a dir="ltr" href="https://www.wunderground.com/blog/weatherhistorian/an-investigation-of-death-valleys-134f-world-temperature-record.html" rel="noreferrer noopener">lengthy 2016 take-down </a>of the record, geographer William T. Reid and weather historian Christopher Burt also raised concerns about the observers’ credibility to accurately record temperatures, exaggerating the temperature beyond what anyone could explain meteorologically.

“Things can always go wrong,” McKinnon says. “People can misrecord temperatures, which is probably the most likely situation”

This isn’t the first time a global heat record has been challenged. Back in 2012, a reading of <a dir="ltr" href="https://www.eurekalert.org/pub_releases/2012-09/asu-wht091112.php" rel="noreferrer noopener">136.4 degrees Fahrenheit in El Azizia, Libya on Sept. 13, 1922, was removed </a>from its record-holding spot after an international team found five major concerns with the recording, from unreliable equipment to an inexperienced observer. And there’s certainly a chance that the 1913 Death Valley record could come into reassessment under the <a dir="ltr" href="https://www.ncdc.noaa.gov/extremes/ncec/," rel="noreferrer noopener">National Climate Extremes Committee </a>.

And even though our systems are much more accurate nowadays, with automated readings and no deciphering of hand-written notes, there’s still a chance that our modern systems may mess up. “You can certainly have problems at individual sites,” Erdman says, “But those are pretty rare.” Just take some of <a dir="ltr" href="https://www.baynews9.com/fl/tampa/weather/2018/10/05/weather-blog--tampa--record-highs--caused-by-sensor-error" rel="noreferrer noopener">Tampa’s 2018 record highs that ended up being inaccurate </a>due to being too closely located to toasty parking lots and highways, picking up too-high temperatures.

Just like every anomaly, there’s a chance that the old record was truly a one-in-a-million occurrence. But whether it stands or not, what really matters is that these records are being broken more and more often in a pattern, we cannot ignore—temperatures are rising worldwide, and the entire planet is now experiencing the wrath of intensified weather.

“What you’re gonna see is that there’s an upward trend,” McKinnon says. “And you can see breaking records with a greater probability.”

<a dir="ltr" href="https://www.popsci.com/authors/sara-kiley-watson/">Sara Kiley Watson </a>is an assistant editor at PopSci. Her work has also been featured in NPR and Business Insider. Contact the author <a dir="ltr" href="mailto:sarakiley@popsci.com" title="Contact to Sara Kiley Watson">here. </a>

What the 'hottest day on record' really means | Popular Science

Death Valley National Park

How We Record Temperatures

Why Temperatures Matter

CURATED BY

Related collections

More like this