25/08/2026
Record-High Ocean Temperatures Raise Alarm for South Africa Ahead of Summer
Global ocean temperatures have climbed to unprecedented levels, raising fresh concerns about what unusually warm seas could mean as the Southern Hemisphere heads towards its warmest months.
The Copernicus Climate Change Service confirmed that the daily average sea surface temperature across the extra-polar global ocean reached **21.1°C on 22 August 2026**, surpassing the previous record of 21.09°C set in March 2024. Scientists say the latest milestone highlights the exceptional amount of heat being stored in the world's oceans. ([Copernicus Climate Service][1])
The development is particularly concerning for Southern Hemisphere countries such as South Africa, where spring and summer are approaching.
# # South Africa could feel the effects
Warm oceans can influence weather systems by providing additional heat and moisture to the atmosphere. However, scientists caution that record ocean temperatures do not automatically mean that every location will experience the same weather extremes.
For South Africa, one of the biggest concerns is the combination of higher temperatures and the developing **El Niño** climate pattern.
The World Meteorological Organization's seasonal outlook has indicated an increased likelihood of above-normal temperatures across southern Africa, while unusually warm sea surface temperatures are also expected across large sections of the world's oceans. ([World Meteorological Organization][2])
El Niño has historically been associated with hotter and, in many parts of southern Africa, potentially drier summer conditions. This could increase pressure on water resources, agriculture and communities already vulnerable to extreme heat.
Prolonged hot and dry spells can also increase the risk of veld fires, crop stress and heat-related health problems.
# # Marine life and fisheries also at risk
The danger is not limited to conditions on land.
Periods of unusually high ocean temperatures can develop into marine heatwaves, placing stress on fish, seabirds and other marine species. South Africa's Department of Forestry, Fisheries and the Environment has previously highlighted marine heatwaves as an emerging climate risk.
Research off the Cape Peninsula found that marine heatwaves can affect biodiversity and cold-water species, while government research has also documented changes in the distribution of some marine species as ocean conditions shift. ([Forestry and Fisheries Department][3])
That matters for a country where thousands of livelihoods depend directly and indirectly on fisheries and healthy coastal ecosystems.
Researchers monitoring South Africa's Prince Edward Islands have also observed warmer waters increasingly reaching ecosystems normally dominated by colder conditions, prompting warnings that changing ocean temperatures could disrupt marine biodiversity. ([Forestry and Fisheries Department][4])
# # Why scientists are watching closely
The latest ocean record comes after months of extraordinary warmth.
July 2026 recorded an average extra-polar sea surface temperature of **20.96°C**, the highest July figure in the Copernicus dataset. By the end of that month, daily temperatures were already approaching the previous all-time record. ([Copernicus Climate Service][5])
Scientists say human-driven climate change remains the long-term force behind rising ocean temperatures, while natural climate patterns such as El Niño can temporarily push temperatures even higher.
For South Africa, the months ahead will therefore be watched closely.
While it is still too early to determine exactly how individual weather events will unfold, record ocean warmth, strengthening El Niño conditions and forecasts for above-normal temperatures mean households, farmers, municipalities and coastal industries may need to prepare for another challenging warm season.