On social networks, misinformation based on weather maps

Climate change critics have found a viral way to spread skepticism on social media during a heat wave: posting weather maps out of context, suggesting that forecasters are exaggerating climate change by overusing the color red.

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During the last two heat waves in Europe, Internet users of different countries and languages ​​misleadingly made weather maps taken from different media on incomparable dates.

These posts generally indicate that the color of the cards has been changed to red, by the media or authorities seeking to create panic.

AFP’s digital verification service has deconstructed several versions of these claims, which have appeared in English, German, Spanish, French, Hungarian and Polish.

In France, two maps, supposed to prove that the media intentionally want to scare people due to the 2022 heat wave, have been shared several thousand times on social networks since July 15.

For a very real map of France’s temperatures on July 17, netizens disputed purported weather forecasts with similar temperatures in 2002, but less red, suggesting that the media is deliberately exaggerating their coverage of this summer’s extreme heat.

“20 years between these two cards… at that time, they were probably doing less brainwashing… living in fear, fearing tomorrow… the media is doing real psychological work on the population… and it’s working not so bad”, As a surfer says on Facebook.

“What a climate catastrophe today was a beautiful summer day in 2002…” a Facebook post on July 16 regrets.

The problem is, the second map is actually from 2019, and the maps came from different sources that didn’t use the same gradients and colors — not, as the post claimed, from a single weather forecaster who messed with his color palette.

Similar leaflets were distributed in May and June, mainly in English and German.

In an example also shared in French on Twitter and elsewhere, two maps of Sweden, side by side, showed similar temperatures: one green and dated 1986, while the other was orange and dated 2022, meaning that over the years, the same temperatures would coincide To more and more annoying colors.

In fact, a numerical investigation revealed that the years indicated on the cards were not correct, and that they came from different media, again using different color codes.

Another type of viral climate post, in Spain, users shared a newspaper photo dating back to 1957 that reported a record temperature of 50 degrees Celsius. The article was correct, but Spanish meteorologists made it clear that the temperature measurement had not been officially adopted or recorded.

Climate scientists agree that carbon emissions from humanity’s burning of fossil fuels are warming the planet, increasing the frequency and intensity of heat waves and other extreme weather events.

With temperatures exceeding 40 degrees Celsius, the heat wave that hit Britain this week has drawn comparisons to the summer of 1976 when the temperature reached 35.9 degrees Celsius. Experts explain that this precedent in no way contradicts the idea of ​​increasing heat waves.

“Of course there have been heat waves in the past, but the big difference with 1976 is the state of the rest of the world,” explains Frederic Otto, a researcher at the Grantham Institute for Climate Change at Imperial College London. “In 1976 there was a heat wave (in Great Britain), in 2022 there were heat waves all over the world, and there were also heat waves in 2021, 2020 and 2019.”

Detailed fact checks mentioned in this article are available on the site factual.afp.com.