Key facts
- Ocean temperatures reached a record 21.1 degrees Celsius (70 degrees Fahrenheit) on Friday and Saturday.
- The warming is driven by a combination of El Nino and human-caused climate change.
- Warmer oceans are expected to destabilize weather patterns, increase storm intensity, and threaten food security.
- The ocean's capacity to hold oxygen decreases as temperatures rise, impacting marine life.
- The current El Nino is still growing and is projected to peak between November and January, likely causing further ocean warming.
The world's oceans have recorded their hottest temperatures on record, reaching 21.1 degrees Celsius (70 degrees Fahrenheit) on Friday and Saturday, narrowly surpassing the previous daily record set in March 2024. This warming trend is attributed to a growing El Nino phenomenon combined with long-term climate change driven by human activities.
Samantha Burgess, strategic climate lead for Copernicus, described the situation as a sign of the climate system and oceans being under immense strain. Oceanographer Jane Lubchenco expressed deep concern, stating that such warm oceans destabilize weather patterns and threaten food security, economic prosperity, and marine life.
Warmer ocean waters lead to increased acidity and reduced oxygen content, negatively impacting marine ecosystems and industries reliant on them. The phenomenon also alters ocean currents and weather patterns, potentially intensifying storms and increasing storm surge impacts. Furthermore, warmer oceans can amplify heatwaves by diminishing the cooling effect of sea breezes.
While ocean temperatures typically peak in March and April in the Southern Hemisphere, the record was set in August this year. The oceans are expected to continue warming until the current El Nino reaches its peak, anticipated between November and January. Scientists like Boris Worm and John Bruno are particularly worried about the consequences for marine life, including potential fisheries collapse, such as the Peruvian anchovy fishery, and the severe impact on coral reefs.