Record ocean heat could worsen, as El Niño strengthens, WMO warns

• In the first half of the year, sea surface temperatures were already above 21°C in tropical oceans, with the highest readings seen so far.
• The WMO says that the El Niño event is developing with increasing strength, with sea surface temperatures in some regions reaching more than 2°C above normal.
• According to the WMO, the sea surface temperature anomaly is likely to exceed 60 p.p. in the coming months. By 60 p.p. it means the difference between the current value and the long-term average for the same period, expressed as a percentage.

According to The Conversation, Asharq Al-Awsat,

Sea surface temperatures in June were the highest on record worldwide, with sea surface temperatures in tropical oceans exceeding 21°C. Based on data from The Conversation, sea surface temperature was about 19.6°C for the period from 1870 to 2025.

The Conversation material says that over 90% of the excess heat is retained by the ocean, where it is absorbed and stored. As a result, oceans are warming, and by 2025 they may contain even more heat than before—potentially increasing the risk of extreme events.

According to the WMO, El Niño is expected to further intensify the warming of the oceans. In particular, the WMO notes that, according to the publication, the strength of El Niño has been increasing over the past few months, and it is likely to continue to strengthen; the organization also points to the possibility of a third consecutive year with El Niño conditions.

For the WMO, the seasonal forecast indicates that sea surface temperatures in some regions may be more than 2°C higher than normal. The material also notes that the model of climate change indicates that the atmosphere above the ocean will warm further as El Niño intensifies.

The Conversation publication explains that ocean heat can be linked to climate cycles, increasing atmospheric temperatures and also affecting the intensity of weather events. The author of the material also states that El Niño, which forms in the tropical Pacific Ocean, may continue to warm the ocean and atmosphere in the Indian Ocean, the tropical Atlantic, and the eastern Pacific.

The Conversation material also points out that ocean temperature anomalies in Europe: could reach 6°C higher than normal, while the ocean off the coast of the Mediterranean could be up to 3°C higher. It also notes that the central-south Atlantic Ocean could warm by more than 1.24°C on average, and the tropical Atlantic could warm by as much as 6°C compared with the average.

The WMO also says that the forecast for the coming months indicates that sea surface temperatures could be more than 60 p.p. higher. The WMO adds that this is likely to be caused by the fact that El Niño changes the ocean-atmosphere system, which can lead to stronger heat transfer and more intense weather patterns.

Tags: Weather/Ecology/Research