Earth's average temperature remained at a record high Wednesday after two days in which the planet reached unofficial records. It's the latest marker in a series of climate-change-driven extremes.
The average global temperature was 62.9 degrees, according to the University of Maine's Climate Reanalyzer, a tool that uses satellite data and computer simulations to measure the world's condition. That matched a record set Tuesday and came after a previous record of 62.6 degrees was set Monday.
Not only that but last month was the world's hottest June since records have been kept, the European Union's climate monitoring service said, according to Agence France-Presse. "The month was the warmest June globally ... exceeding June 2019 -- the previous record -- by a substantial margin," the EU monitor said in a statement from its C3S climate unit.
Scientists have warned for months that 2023 could see record heat as human-caused climate change, driven largely by the burning of fossil fuels like coal, natural gas and oil, warmed the atmosphere. They also noted that La Nina, the natural cooling of the ocean that had acted as a counter to that warming, was giving way to El Nino, the reverse phenomenon marked by warming oceans. The North Atlantic has seen record warmth this year.
"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.
University of Maine climate scientist Sean Birkle, creator of the Climate Reanalyzer, said the daily figures are unofficial but a useful snapshot of what's happening in a warming world.
While the figures are not an official government record, "this is showing us an indication of where we are right now," said National Oceanic and Atmospheric Administration chief scientist Sarah Kapnick. And NOAA indicated it will take the figures into consideration for its official record calculations.
Even though the dataset used for the unofficial record goes back only to 1979, Kapnick said that given other data, the world is likely seeing the hottest day in "several hundred years that we've experienced."
Scientists generally use much longer measurements - months, years, decades - to track the Earth's warming. But the daily highs are an indication that climate change is reaching uncharted territory.
Some parts of the world saw extraordinary heat waves.
High-temperature records were surpassed this week in Quebec and Peru. Beijing reported nine straight days last week when the temperature exceeded 95 degrees and ordered a stop to all outdoor work Wednesday as high temperatures were forecast to pass 104 degrees.
The marks were set in communities that aren't used to feeling such heat. North Grenville, Ontario turned ice hockey rinks into cooling centers Wednesday as temperatures hit 90 degrees, with humidity making it making it feel like 100 degrees.
"I feel like we live in a tropical country right now," city spokeswoman Jill Sturdy said. "It just kind of hits you. The air is so thick."
Some 38 million Americans were under some kind of heat alert Wednesday, Kapnick said.
Cities across the U.S. from Medford, Oregon to Tampa, Florida have been hovering at all-time highs, said Zack Taylor, a meteorologist with the National Weather Service.
But according to data from the Climate Reanalyzer, many of the largest temperature anomalies this week was seen over the world's oceans, especially the Antarctic Ocean.
"Temperatures have been unusual over the ocean and especially around the Antarctic this week because wind fronts over the Southern Ocean are strong, pushing warm air deeper south," said Raghu Murtugudde, professor of atmospheric, oceanic and earth system science at the University of Maryland and visiting faculty at the Indian Institute of Technology, Bombay.
Murtugudde said ocean heat is also going deeper. He said, "Oceans take up 93% of additional heat we are generating because of increasing greenhouse gases and they are now a huge reservoir of heat."
Some places experienced unusually cold weather for the time of year, including southeast Australia and much of India.
With many places seeing temperatures near 100.40 degrees, an average temperature record of 62.9 degrees might not seem very hot. But Tuesday's global high was nearly a 1.8 degrees higher than the 1979-2000 average, which already topped the 20th- and 19th-century averages.
Alan Harris, director of emergency management for Seminole County, Florida, said the county has already surpassed last year for the number of days it's activated its extreme weather plan - something that happens when the heat index hits 108 degrees or greater.
"It's just been kind of brutally hot for the last week, and now it looks like potentially for two weeks," Harris said.
In the U.S., heat advisories include portions of western Oregon, inland far Northern California, central New Mexico, Texas, Florida and the coastal Carolinas, according to the National Weather Service Weather Prediction Center. Excessive heat warnings are continuing across southern Arizona and California.