The world's oceans have reached their highest temperature on record, with an average surface temperature of 21.1C (70F) outside the polar regions. This is attributed to human-caused climate change and the growing El Niño weather phenomenon. Warmer oceans can have severe consequences, including supercharging extreme weather, raising sea levels, and harming marine life. The record temperature is particularly notable as it occurs in August, a time when ocean temperatures are typically not at their peak.