UN Geneva - Multimedia Newsroom : Warmest July on record

UN weather agency warns that July likely warmest on record

As wildfires raged across Southern Europe and North Africa, top UN and partner agency climate scientists said on Thursday that it was virtually certain that July 2023 will be the warmest on record.

“We can say that the first three weeks of July have been the warmest three-week period ever observed in our record,” said Carlo Buontempo, Director of Copernicus Climate Change Service at the European Centre for Medium-Range Weather Forecasts (ECMWF). “If we look at the top 21 hottest day in terms of the global mean temperature, they have all occurred this month.”

Echoing that warning in New York, UN Secretary-General António Guterres said that “short of a mini-Ice Age” in coming days, July 2023 would likely “shatter records across the board”.

The UN chief added that the consequences were as clear as they were tragic: “children swept away by monsoon rains, families running from the flames (and) workers collapsing in scorching heat.”

In Geneva, Chris Hewitt, Director of Climate Services at the World Meteorological Organization (WMO) described conditions this month as “remarkable and unprecedented” and urged action on climate shock adaption.

At the same time, Copernicus’s Mr. Buontempo said that the July anomaly was “so large with respect to other record-breaking months in our record that we are virtually certain that the month, the month as a whole will become the warmest July on record, the warmest month on record”.

From a historical perspective, July’s likely record conditions have been driven by concentrations of greenhouse gases in the atmosphere which continue to increase, explained Mr. Hewitt. “The three main greenhouse gases - carbon dioxide, methane and nitrous oxide - have all reached record observed highs,” he said, adding that there was “an almost certain likelihood” that one of the next five years will be the warmest on record.

Equally concerning is the clear indication that there is now a 66 per cent chance that global average temperatures will “temporarily” exceed 1.5C above pre-industrial levels “for at least one of the five years”, Mr. Hewitt continued.

Turning from the impact of rising global temperatures on land to the sea, the climate scientists warned that ocean temperatures are also at their highest-ever recorded levels for this time of year. This trend has been apparent since the end of April.

Citing “a clear and dramatic warming decade on decade” since the 1970s, WMO’s Mr. Hewitt noted that 2015 to 2022 saw the eight warmest years on record, based on a 173-year dataset. This was despite the fact that the La Niña sea-cooling phenomenon prevailed towards the end of that period in the Pacific region, which reined in global average temperatures slightly, he explained.

“But now the La Niña has ended” - to be replaced by the sea-warming El Niño effect - waters have begun to heat up in the tropical Pacific, bringing the “almost certain likelihood that one of the next five years will be the warmest on record”, the WMO scientist continued.

“It’s not looking at the moment like the warmth will abate. And so, if this carries on with the El Niño conditions growing in the Pacific, we could anticipate it being a very warm year, if not a record year. But we'll have to wait and see.”

Underscoring the need for countries to adapt to searing heatwaves, Mr. Hewitt explained that this was necessary “to take care of vulnerable societies or whatever it might be...So, yes, there's a need to adapt to increases in temperature and then as you asked in the question, there are other extremes as well, so, extremes of flooding, droughts, windstorms.”

Echoing that message, Mr. Buontempo warned that “in all likelihood, we have never experienced a world so hot in modern history.”

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