Planet’s Hottest Month Confirmed While Earth Keeps Baking

On the same day that climate agencies in the United States confirmed that July was the planet’s hottest month on record, historic August heat was occurring around the Northern Hemisphere. From the United States to Asia and the Middle East, Monday saw a continuation of extreme heat that has lasted for weeks and even months in many places.

The National Oceanic and Atmospheric Administration confirmed Monday what was already nearly certain: Earth’s average global surface temperature in July was 2.02 degrees above the long-term July average of 60.4 degrees, making July the warmest month in 174 years of record-keeping. It was the 533rd consecutive warmer-than-average month, spanning a stretch of more than 44 years.

“During July 2023, 9.35% of the world’s surface had a record-high July temperature — the highest July percentage,” NOAA said. July was also the fourth consecutive month that global ocean surface temperatures were at record highs.

The record-setting July follows the planet’s warmest June on record. Overall, the first seven months of 2023 ranked as the third-warmest January-to-July, NOAA said. Extreme heat has continued in August in many locations around the globe, with several records reported Monday:

Portland, Ore., surged to a scorching high temperature of 108 degrees, its highest August temperature on record and third-hottest of all-time. Several other locations in the Pacific Northwest also set all-time August records amid the most intense heat since the historic June 2021 heat wave.
Several August and all-time records were set in Louisiana and Florida, including Alexandria, La., and Natchitoches, La., both of which reached 108 degrees. In New Orleans, the temperature reached at least 100 for the fifth straight day, its longest 100-degree stretch on record.
The Pacific Northwest heat extends into British Columbia, where at least 16 daily records highs were set. Lytton reached a high of 106.5 degrees (41.4 degrees Celsius), Canada’s highest temperature this year, while Lillooet topped out at 105 degrees (40.7 degrees Celsius).
In Japan, Nagaoka, about 130 miles north of Tokyo, topped out at 103 degrees, which was an all-time record high. Meanwhile, the low temperature in Itoigawa, about 60 miles to the southwest, didn’t fall below 90.5. That marked Japan’s highest overnight minimum on record and comes amid an extended stretch of extreme heat across Asia. “This heat wave in Japan has no similarities of anything seen in the past,” weather historian Maximiliano Herrera tweeted.
Khanaqin, Iraq, has recorded its seventh straight high temperature above 122 degrees and seventh straight low temperature above 86 degrees, as central and northern portions of the country are “living the worst heat wave in its history,” Herrera tweeted. At least three locations failed to drop below 98 degrees Monday.

The presence of El Niño, which NOAA gives a 95 percent chance of lasting through the winter, favors a continuation of the worldwide warmth. “It is virtually certain (> 99.0%) that 2023 will rank among the five-warmest years on record, with a nearly 50% probability that 2023 will rank as the warmest on record,” NOAA said.

Berkeley Earth was even more bullish in its projections for warmth this year, concluding that it’s “virtually certain” 2023 will be the warmest year on record for the planet.

By Dan Stillman