Scientists have recorded the highest temperature ever measured in the world’s oceans, as climate change combines with a powerful El Nino in the tropical Pacific. The global average sea-surface temperature hit a record 21.1 degrees Celsius (70 Fahrenheit) on August 22, according to Europe’s Earth observation agency Copernicus, which has been tracking the metric daily since 1979. The previous single-day record of 21.09 degrees was measured in March 2024. “El Nino is adding heat to the system, but...