A warm month marked by record heatwaves, massive wildfires, melting sea ice and the rise of El Niño will set to be the warmest July on record, at least until next year, federal officials said on Monday.

Last month, the planet and its oceans caught fire as the average global temperature rose 2.02 degrees above average, making July 2023 not only the hottest July on record, but also possibly the hottest month on Earth in at least 174 years of record.

“From a climatological standpoint, July is the hottest month of the year,” the National Oceanic and Atmospheric Administration said in its monthly report released Monday. “July 2023, the hottest July on record, was, at least supposedly, the hottest month on record for the world.”

According to the agency, temperature data through July guarantees that with almost 50% probability 2023 will be among the five warmest years on record. The announcement came as no surprise to the millions of Americans affected firsthand by the extreme heat.

The stubborn presence of a high-pressure heat dome in the American Southwest has caused temperatures in Phoenix to hit a record 110 degrees or higher for 31 consecutive days. More than 40 deaths have been reported in the county, hundreds are under investigation, and dozens of people have been hospitalized for heat-related illnesses and sidewalk burns.

High-temperature wildfires in Greece, Italy, Canada and Algeria have released toxic fumes, forcing residents and tourists to flee for safety. Death Valley rose to 128 degrees, while regions in northwest China rose to 126 degrees. A number of factors caused the heatwave, according to Caryn Gleason, director of the monitoring division at NOAA’s National Centers for Environmental Information.

The onset of El Niño, a climate pattern in the tropical Pacific, warmed regions around the equatorial Pacific, pushing land and ocean temperatures to new extremes. The surface temperature dropped 0.36 degrees above the previous July record set in 2021.

“The warmest month on record for land was the warmest month on record for oceans, and when combined, it was the warmest month on record for land and ocean anomalies,” said Gleason. “So he broke records in all three categories.”

It’s definitely a big deal to see Asia, Africa and South America record the warmest July months, and “to see the three major continents experience their warmest July months on record,” he said. The oceans were also affected by the heat, and July was the fourth month of record high global ocean surface temperatures.

This month, which was 1.78 degrees above normal, saw the highest monthly sea surface temperature anomaly for any month in the NOAA climate record. Ocean temperatures off the Florida coast reached an unprecedented 101 degrees, about the temperature of a whirlpool.

But Gleason noted that El Niño isn’t the only one to blame.

He said the model has rarely followed its La Niña counterpart for three consecutive years, which is known to have a cooling effect that may have masked an ongoing warming trend in some areas.

“Because we were in that long La Niña period, we actually felt like the Earth wasn’t warming while the rest of the ocean basins outside the eastern equatorial Pacific were warm and slowly warming,” Gleason said. “But now these waters are warming, shedding light on how warm other ocean basins really are.”

This greater warming trend is almost entirely due to human-induced climate change, said climate scientist Daniel Swain of the University of California, Los Angeles.

“To sum it up in two words, global warming is definitely the dominant effect,” Swain said. He noted that El Niño is not yet fully developed and the corresponding increase in global temperatures is usually strongest towards the middle and end of the event.

“El Nino potentially helps explain why this July is the hottest month on record, but it doesn’t explain why we’ve gotten to the point where we break these temperature records all the time,” he said. “Maybe more than 80%, maybe even more than 90%, is simply due to the accumulation of greenhouse gases in the atmosphere.”

There could be some tertiary factors contributing to the record temperature, including the 2022 eruption of Hunga Tonga volcano, which released record amounts of heat-trapping water vapor into the stratosphere, Swain said.

He said major changes in shipping regulations may also have played a minor role.

Rules adopted by the International Maritime Organization in 2020 lowered the upper limit for the sulfur content in fuel to achieve cleaner air in ports and coastal areas. But this change can have unintended consequences, as aerosols help reflect some of the sunlight from Earth.

Swain said that unusually warm water is in some ways more noticeable than warm land because more energy is required to warm the ocean. “Imagine how much energy it takes to boil a pot of water,” he said.

Such abnormally high ocean temperatures could have cascading effects, such as the mass bleaching of coral reefs in the Caribbean and Gulf of Mexico, which NOAA says could lead to significant deaths.

“There is a real concern among many scientists who study these reefs that this may be just the case – there may be a regional or local death to many coral reefs in these areas this summer because it was incredibly hot,” Swain said. aforementioned

Warmer temperatures also helped melt sea ice, and July set a record for the world’s lowest July sea ice size, about 470,000 square miles less than the previous low in July 2019.

It was the third consecutive month of record-low Antarctic sea ice, “the size of Argentina,” about one million square miles below the 1991-2020 average, NOAA said. While conditions may seem untenable, officials say global warming is only expected to get worse.

“While July is unusually warm at the moment, we expect this to continue for the rest of the year overall,” said Gleason. “If the forecast continues through the winter months, we don’t see immediate relief.” Indeed, NOAA’s Climate Prediction Center has put the probability of El Niño continuing through the winter at 95%, meaning 2024 could get off to an even warmer start.

“I think everyone in the climate community expects the winter months to be very warm,” Gleason said. Said. “And 2024 may surpass 2023 before all is said and done.” Source