Daniel Wolfram
Global warming just contributed to a concerning record this past August.
According to the Copernicus Climate Change Service, Earth’s atmosphere held more water vapour this past August than in any other month on record.
Data from the agency shows moisture levels reached 27.35 kilograms per square metre.
That broke the previous record set in July 2024. This is a global climate phenomenon also known as El Niño–Southern Oscillation (ENSO), or El Niño for short.
Sky full of water
While a small numerical bump might sound minor, scientists say it represents a massive shift in atmospheric water.
Professor Jason Evans from the UNSW Climate Change Research Centre calculated that the extra moisture equals roughly 20 trillion litres.
Dr Andrew Dessler, a climate scientist at Texas A&M University, highlighted the historic scale. According to The Guardian, he wrote that it was “unimaginable that any month in the last few thousand years, maybe 100,000 years” contained so much water vapour.
El Niño
Record global temperatures and the powerful El Niño in the Pacific Ocean drove the spike. As sea surfaces heat up, evaporation speeds up, pumping vast amounts of steam into the sky.
Dr Julien Nicolas, a senior scientist at C3S, explained that “warmer air can hold about 7% more water vapour per degree of [global] warming.”
This extra energy increases the risk of torrential rain and severe cyclones. Meanwhile, high humidity traps heat near the ground, making heatwaves more frequent and dangerous.
Professor Steven Sherwood of the UNSW climate centre stressed that humidity blocks night-time cooling. He noted, “We know high humidity has effects during heatwaves as it stops night-time cooling, so it gets harder for people to recover from very hot days.”
Endless loop
Climate experts warn that atmospheric moisture acts as a potent greenhouse gas. When air traps heat, temperatures rise further, causing oceans to evaporate even faster.
Dr Kimberley Reid from the University of Melbourne stressed that “temperature and water vapour are closely linked.” She emphasized that fossil fuel emissions and El Niño drive these records.
With climate patterns changing, researchers expect extreme humidity to persist. In the words of Dr Dessler, “We are, as the proverb says, living in interesting times.”
