Ahead of the United Nations Climate Change Conference, or COP28, which starts Nov. 30, Climate Central released a report Thursday showing the past 12 months were the hottest on record.
Daily average temperatures and heat waves were analyzed for 175 countries, 154 states/provinces, and 920 major cities.
The period between November 2022 and October 2023 was warmer by an average of 1.32°C, scientists said. That’s compared to the pre-industrial baseline set between 1850 and 1900.
The previous record for the warmest 12-month period was between October 2015 and September 2016 at 1.29°C above the baseline. The period ending in September 2023 then tied this record.
Within the most recent period ending in October, 90% of people — or 7.3 billion — experienced at least 10 days of temperatures that were hotter mostly due to human-induced climate change, and 73% — or 5.8 billion — experienced more than a month’s worth of these temperatures.
"We don't experience 1.3 degrees. We experience our daily weather, right? That's how climate change impacts us," said Andrew Pershing, vice president for science at Climate Central. He spoke on a panel during a virtual media conference Wednesday.
Extreme heat in Florida
A handful of Florida cities were listed in the report for having extreme heat days, which are defined as warmer than 99% of days in a 30-year normal.
Miami had the most extreme heat days with 34. Tampa had 23, Tallahassee and Jacksonville both had 14, and Orlando had 11.
“El Niño is really going to start to bite next year, and so that's going to lead to even more warming as we move on into 2024.”Andrew Pershing, vice president for science at Climate Central
Miami experienced two heat streaks that lasted more than five days — the longest being 10 days starting Aug. 6.
Tampa and Orlando each had heat streaks that lasted seven days starting Aug. 7.
Tallahassee’s heat streak lasted five days starting Aug. 10, which was the same day Jacksonville’s six-day streak began.
Even hotter in 2024
“The southern U.S., especially Houston with 22 days … had the longest streak among the large cities around the world,” said Pershing.
“But Mexico City and a couple other places in the southern U.S. and Mexico had very long streaks. We had long streaks in Indonesia, and in China, but you can see they're really occurring everywhere around the world during the last 12 months.”
He said we can expect even more warming next year due to weather patterns.
“El Niño is really going to start to bite next year, and so that's going to lead to even more warming as we move on into 2024,” Pershing said.
Based on historical data, the report said it is highly likely that the next 12 months will be even hotter, possibly exceeding 1.4°C above the baseline.
"These impacts are only going to grow as long as we continue to burn coal, oil and natural gas — that is the ultimate driver of the changes that we're seeing around the planet,” Pershing said.
Extreme heat solutions
The report said rapidly reducing carbon pollution every year is required to halt the warming trend.
Friederike Otto, with the Grantham Institute and World Weather Attribution, also spoke about solutions Wednesday, pointing to the latest Intergovernmental Panel on Climate Change report.
“One of the most important findings of the IPCC report that somehow no one talked about: so, when we stop burning fossil fuels, temperatures will stop rising,” Otto said.
“We are very certain now that when we stop burning fossil fuels, so when we stop adding fossil fuels into the atmosphere, the greenhouse gases into the atmosphere, global temperatures will stop rising, which means that heat waves will stop getting worse, extreme rainfall events will stop getting worse.”
