The weather map of southern Europe remains a deep, sinister red, as the heat soars above 40C in places and closer to 50C in Sicily and Sardinia. In Madrid, some nights are equatorial rather than tropical, as the temperature stays above 25C. June was the hottest month recorded on Earth for 120,000 years. The hottest week came early this month. “Very dangerous long-duration heat”, to use the language of the recent alert issued by the US National Weather Service in Arizona, sums up the experience of the last few weeks across much of the northern hemisphere. Extreme heat, wildfires and floods are ravaging parts of the US, Canada, Japan, South Korea, India and China.
Global heating is not the sole explanation for the hellish impact of Cerberus and Charon, the heatwaves named after mythical denizens of Hades. As in 2016 – the hottest year ever recorded – an emerging El Niño weather pattern is helping drive the barometer upwards. But each time this natural and sporadic event recurs, typically adding 0.2C to the average global temperature, it heats up a planet that is already warmer than before as a result of greenhouse gas emissions.
