As activists convert summer heat into hysteria, one instigator of the panic — the University of Maine’s Climate Reanalyzer — adds a “special notice” alerting readers that its figures are “estimated” and not “‘official’ observational records.” This raises hopes that cooler heads might prevail.

“The earth just broke the record for the hottest day in 120,000 years,” a Democratic congresswoman from Minnesota, Ilhan Omar, tweeted on Monday. “In fact, we broke it on three separate days.” Scary stuff, but in the time since the heat headlines burned across the world, the “settled science” made a quiet shift to conjecture.

“The source for this claim,” Twitter wrote in a community note for context, “appears to be the … Reanalyzer which has added a recent notice making it clear that it should not be taken as official observation records.” This poured cold water on the hype, hanging alarmists like Ms. Omar out to dry.

“The mean global temperature increases in early July 2023,” the Reanalyzer writes halfway down a back page, “estimated from the Climate Forecast System, should NOT be taken as ‘official’ observational records,” never mind how they were presented.

“When news reports declared July 4 ‘the hottest day ever,’” as I wrote in the Sun a week ago, “readers could be forgiven for being concerned.” The Reanalyzer, though, “has aggregated and modeled ‘average global temperatures’ from select locations since only 1979,” not even the blink of a blink in the earth’s long life.

“Biden’s EPA,” the head of Climate Depot, Marc Morano tells me, “shows the 1930s heat waves were much, much worse in the U.S. than recent times.” He also tells me that many studies and data disclose that the “Roman Warming Period and the Medieval Warm Period were as warm or warmer than today.”

The EPA website does indeed show a huge spike during the Dust Bowl, which, it says, “brought some of the hottest summers on record to the United States,” but nobody seems to care much about a hundred years ago when there’s self-pity — meaning taxes to be raised — today.

The United Nations, preposterously cited as an authority, “acknowledged these facts in their first climate report in 1990 before they later altered the data and erased the Medieval Warm Period,” Mr. Morano says. “Congresswoman Omar is just regurgitating the latest media hype promoted by the climate agenda.”

Ms. Omar and other alarmists don’t start the clock in the Medieval Period, 1905, the 1930s, or even 44 before the common era, when Julius Caesar wound up on the wrong end of several daggers, but 120 millennia ago, when there were no thermometers, which Daniel Fahrenheit invented only in 1714. Any figures, therefore, are, at best, just more estimates.

Other stories about the heat are doubtful, too. CBS News, referring to Rome as an “ancient city” as if to imply that its heat records go back to some sweaty centurion, reported that it had hit “a new local record-high temperature on Tuesday and that “all agreed that it had tipped over the previous record of 106 degrees.”

A search of the Sun archives, however, adds a little context of our own. In 1905, also on July 4, we reported “the thermometer registered 100 degrees in the shade in Rome and 104 in Florence,” with highs of 113 degrees in some districts and 17 heat-related deaths between the two cities compared to one in the entire country as of July 12.

Considering the construction at Rome and Florence in the century-plus since, ought we not take into account the “heat island effect,” which the EPA explains can drive “daytime temperatures in urban areas are about 1-7°F higher” as well as the advances in — and proliferation of — temperature monitoring stations?

“Without intended disrespect to science,” the Sun wrote of fears about a “cooling earth” in 1912, “we take melancholy pleasure in the assurance that long before the solar system ‘runs down,’ we shall have attained Nirvana,” and our Big Blue Marble will take no more notice of our departure than it does our actions, its ever-changing climate the only thing we can count on as an official truth.