Global warming and El Niño push atmospheric water vapour to record high
Scientists warn that record atmospheric moisture is strengthening storms, bringing heavier rain, worsening heatwave conditions and accelerating a climate feedback loop.
- Atmospheric water vapour reached a record high in August, a result of the combined effects of global warming and the current El Niño event.
- Global warming is a primary driver, as warmer air can hold significantly more moisture (7% for every 1°C rise).
- El Niño contributes by raising sea surface temperatures, which increases the rate of evaporation into the atmosphere.
- This record-high water vapour intensifies storms, worsens heatwaves, and acts as a greenhouse gas, creating a feedback loop that further raises global temperatures.
The European Union’s Copernicus Climate Change Service (C3S) has released concerning data showing that the amount of water vapour in the global atmosphere reached 27.35 kilograms per square metre in August, the highest level ever recorded.
The increase from the previous record was equivalent to more than 20 trillion litres of water.
Global warming was a key factor, as warmer air can hold 7% more moisture for every 1 degree Celsius rise in temperature.
This was compounded by El Niño in the Pacific Ocean, which has raised sea surface temperatures and increased evaporation into the atmosphere.
Scientists warned that this vast accumulation of atmospheric water vapour was having severe knock-on effects across natural systems, particularly by supplying cyclones and storms with vast amounts of additional energy.
Heat is released when water vapour condenses to form clouds.
This strengthens storms and produces heavier-than-normal rainfall in many areas around the world.
High atmospheric humidity also compounds the impact of heatwaves by hampering night-time cooling.
This keeps nights persistently hot and humid, directly affecting health because the human body finds it harder to recover from accumulated heat.
Of greatest concern, water vapour also acts as a greenhouse gas that accelerates a climate feedback loop.
It traps more heat and pushes global temperatures higher.
Scientists expect this intense El Niño event to drive global temperatures to successive record highs through next year.
