The El Niño Southern Oscillation, or ENSO as it is also called, is the most powerful fluctuation in the climate system anywhere on Earth. It happens every three to seven years, and in the warming phase, warmer waters come to the surface of the tropical Pacific and push heat into the atmosphere.

“Climate scientists aren’t surprised about the global daily temperature record being broken, but we are very concerned,” Friederike Otto, senior lecturer in climate science at Imperial College London, said.

It “should be a wake-up call for anyone who thinks the world needs more oil and gas,” she added.