Monday might have set a global record for hottest day ever. Then Tuesday broke it

The entire planet sweltered for the two unofficial hottest days in human record keeping Monday and Tuesday, according to scientists at the University of Maine’s Climate Reanalyzer project.

For two consecutive days, the global average temperature spiked into uncharted territory. After scientists talked about Monday’s dramatic heat, Tuesday pushed the mercury up another 0.31 degrees — a huge temperature jump in terms of global averages and records.

The same University of Maine climate calculator, which uses satellite data and computer simulations, forecasts a temperature in similar record territory for Wednesday, with an Antarctica average that is a whopping 8.1 degrees warmer than the 1979-2000 average.

High temperature records were surpassed Monday and Tuesday in Quebec, northwestern Canada and Peru. Cities across the U.S., from Medford, Ore., to Tampa, Fla., have been hovering at all-time highs, said Zack Taylor, a meteorologist with the National Weather Service. Beijing reported nine straight days last week when the temperature exceeded 95 degrees.

“The increasing heating of our planet caused by fossil fuel use is not unexpected — it was predicted already in the 19th century after all,” said climate scientist Stefan Rahmstorf at the Potsdam Institute for Climate Research in Germany. “But it is dangerous for us humans and for the ecosystems we depend on. We need to stop it fast.”

The daily but preliminary and unofficial heat record comes after months of “truly unreal meteorology and climate stats for the year,” such as off-the-chart record warmth in the North Atlantic, record low sea ice in Antarctica and a rapidly strengthening El Niño, said University of Oklahoma meteorology professor Jason Furtado.

This global record is not quite the type of measurement regularly used by gold-standard climate-measurement entities like the National Oceanic and Atmospheric Administration. But it is an indication that climate change is reaching into uncharted territory. It legitimately captures global-scale heating, and NOAA will take these figures into consideration when it does its official record calculations, said Deke Arndt, director of the National Center for Environmental Information, a division of NOAA.

“In the climate assessment community, I don’t think we’d assign the kind of gravitas to a single-day observation as we would a month or a year,’’ Arndt said. Scientists generally use much longer measurements — months, years, decades — to track the Earth’s warming. In addition, this preliminary record for the hottest day is based on data that go back only to 1979, the start of satellite record keeping, whereas NOAA’s data go back to 1880.

But Arndt added that the Earth would not be seeing anywhere near record-warm days unless it was in “a warm piece of what will likely be a very warm era” driven by greenhouse gas emissions and the onset of a “robust” El Niño. An El Niño is a temporary natural warming of parts of the central Pacific Ocean that changes weather worldwide and generally makes the planet hotter.

Human-caused climate change is like an upward escalator for global temperatures, and El Niño is like jumping up while on the escalator, Arndt said.

On Tuesday, the Fourth of July, Earth’s average temperature spiked at 62.9 degrees, according to the Climate Reanalyzer. That was about 1.8 degrees warmer than the 1979-2000 average, which is itself is warmer than the 19th and 20th century averages.

On Monday, the Reanalyzer reported the average global temperature at 62.6 degrees Fahrenheit.

“A record like this is another piece of evidence for the now massively supported proposition that global warming is pushing us into a hotter future,” said Stanford University climate scientist Chris Field, who was not part of the calculations.

Hotter global average temperatures translate into brutal conditions for people all over the world.

In the U.S., heat advisories are in effect this week for more than 30 million people in places including portions of western Oregon, inland in the far north of California, central New Mexico, Texas, Florida and the coastal Carolinas, according to the National Weather Service. Excessive heat warnings are continuing across southern Arizona and California, they said.