Global Sea Surface Temperature Hits Record 21.1°C
Copernicus Climate Change Service reports new high, surpassing March 2024 record.
AI-assisted coverage comparison, editor-supervised · How this was made
Temperatura superficial diaria del mar (°C) para 2024 (amarillo), 2025 (naranja) y 2026 (rojo). C3S/ECMWF
Photograph: Eldiario.es (embedded from source)
What this story says
- The average global sea surface temperature reached 21.1°C on August 22, 2026.
- This new record surpasses the previous high of 21.09°C recorded in March 2024.
- Scientists attribute the record temperature to a combination of global warming and the El Niño phenomenon.
- The Mediterranean Sea also recorded a summer high of 33.02°C.
Who covered it
Percentages are shares of the 31 outlets carrying a published leaning rating. 31 of the 62 outlets we know ran this story carry no rating and are not counted in them. Coverage measured .
Trust
42/100
Craft
61/100
Hype
41/100
62 sources · methodology
The average global sea surface temperature reached a record 21.1°C on August 22, 2026, according to the Copernicus Climate Change Service (C3S). This figure surpasses the previous record of 21.09°C, which was set in March 2024. The C3S reported that global ocean temperatures typically peak in March or April, making the August record unusual. This new high follows a series of monthly sea surface temperature records observed throughout 2026, indicating persistent warming.
Scientists attribute this record temperature to the combined effects of ongoing global warming and the El Niño phenomenon. The World Meteorological Organization anticipates El Niño will strengthen in the coming months. The Mediterranean Sea also experienced a record high this summer, reaching 33.02°C.
Disagreement on previous record
While the Copernicus Climate Change Service reported the previous record was 21.09°C in March 2024, one report stated the previous high was 21.09°C in March 2024, and another mentioned a previous record of 20.98°C in 2023. One digest also noted the previous high was recorded in 2024.
What the coverage left out
None of the digests mention the specific figure of 33.02°C for the Mediterranean Sea's record high temperature, which was only detailed in the full report from Eldiario.es.
Still developing. We have re-checked which outlets are covering this 3 times, most recently on 24 Aug 2026, 20:30, and will add the sides that appear.
How each side covered it
Our own reading of the reporting listed below, written from the outlets’ articles rather than quoted from them. The reasoning is set out on our methodology page.
Left
14 rated outlets
- Eight of the 14 left-rated reports highlighted the record sea surface temperature and its connection to climate change and El Niño. Several reports quoted scientists on the unprecedented nature of the warming. Eldiario.es noted that ocean temperatures are rising at a 'dizzying speed' due to climate crisis and El Niño, and quoted Samantha Burgess, strategic climate lead at ECMWF, stating, 'This record is another clear sign that the ocean is under increasing pressure.' The outlet also detailed the consequences of warmer oceans, including sea-level rise and increased intensity of marine heatwaves. Le Huffington Post and HotNews.ro also noted the unusual timing of the record temperature.
Centre
9 rated outlets
- Seven of the nine centre-rated reports focused on the record sea surface temperature and the alarm expressed by scientists. Staten Island Advance and Cleveland.com reported that scientists say the ocean warmth may rival levels not seen for thousands of years. Tagesschau and wz.de highlighted that climate experts find the timing of the measurement unusual. France24 and Euronews mentioned the record temperature and the potential for El Niño to be the most significant known.
Right
8 rated outlets
- Six of the eight right-rated reports focused on the record sea surface temperature, attributing it to global warming and El Niño. Sapo and Observador reported the absolute record of 21.1°C on Saturday. Globo's headline stated that ocean temperature in 2026 is the highest already recorded. N-tv and Frankfurter Allgemeine mentioned El Niño as a reason, but not the only one. La Razón quoted a European expert stating the record is a 'clear sign that the ocean is under increasing stress'.
Questions about this coverage
- How did the left and right cover Global Sea Surface Temperature Hits Record 21.1°C?
- Of the 31 outlets on this story carrying a published leaning rating, 45% are rated left, 29% are rated centre, 26% are rated right. Those percentages are shares of the rated outlets, not of every outlet that ran it, which was 62. The sections above set out what each side emphasised, in its own terms.
- Is Global Sea Surface Temperature Hits Record 21.1°C left or right?
- Neither side dominates it. Of the 31 rated outlets on this story, 45% are rated left, 29% are rated centre, 26% are rated right, and no side holds the 70% this site would want before calling a field one-sided. A story is not left or right in any case; the outlets that carried it are what carry ratings.
- Is the coverage of Global Sea Surface Temperature Hits Record 21.1°C biased?
- Global Sea Surface Temperature Hits Record 21.1°C is one event reported by 62 outlets, and this page does not rate the story as biased or unbiased. What it publishes is the spread: which outlets ran it, where named rating organisations place each of them on the spectrum, and what each side chose to lead with. A leaning rating describes an outlet's record over time, not this article, and the two should not be run together.
- Which outlets covered Global Sea Surface Temperature Hits Record 21.1°C?
- 62 that we know of, every one of them listed further up this page with a link to its own report and to what we hold on the publisher. Nothing here is a summary of somebody else's summary: the outlets are named so the original reporting can be read.
- What was the record global sea surface temperature?
- The average global sea surface temperature reached a record 21.1°C on August 22, 2026. This surpassed the previous record of 21.09°C set in March 2024.
- What is causing the record ocean temperatures?
- Scientists attribute the record ocean temperatures to a combination of global warming and the El Niño phenomenon. El Niño is expected to strengthen in the coming months.
- Did any other bodies of water set temperature records?
- Yes, the Mediterranean Sea also reached a record high this summer, recording a temperature of 33.02°C.
Read it at the source
62 outlets, grouped by the leaning a published rating gives them. Every headline links to the original; an underlined outlet name opens our profile of that publisher.
Left
14- Copernicus Measurement: World Seas with 21.1 Degrees Celsius as Warm as Never Before (opens Spiegel in a new tab)
- The Oceans No Longer End up Heating and Are Beating a New Sad Temperature Record (opens Le Huffington Post in a new tab)
Le Huffington Post — is Le Huffington Post biased? Our profile of this outlet
- The World's Oceans Have Recorded an Absolute Daily Record of Heat. Why Such a Temperature Is Unusual Now - HotNews.ro (opens Hot News in a new tab)
- The World's Oceans Have Warmed to a Record Temperature of 21.1 Degrees. The Previous Maximum Was Recorded in 2024 (opens Meduza in a new tab)
- The Average Temperature of the World's Oceans Is Setting a Historic Record at 21.1°C (opens Liberation in a new tab)
Liberation — is Liberation biased? Our profile of this outlet
- The Oceans Record Their Warmest Day (opens Radio-Canada in a new tab)
Radio-Canada — is Radio-Canada biased? Our profile of this outlet
- Climate Change: Sea Temperatures as High as Ever (opens Sueddeutsche Zeitung in a new tab)
Sueddeutsche Zeitung — is Sueddeutsche Zeitung biased? Our profile of this outlet
- The World's Oceans Reach a Record Daily Average Temperature at 21.1°C (opens franceinfo.fr in a new tab)
franceinfo.fr — is franceinfo.fr biased? Our profile of this outlet
Show 6 more
- The Oceans of the Planet Record the Highest Temperature Since Data (opens El Pais in a new tab)
- Earth's oceans just hit their hottest temperature ever recorded (opens Scientific American in a new tab)
Scientific American — is Scientific American biased? Our profile of this outlet
- Ocean Temperatures Have Reached a Historic High. The Consequences Could Be Serious (opens Novinky.cz in a new tab)
Novinky.cz — is Novinky.cz biased? Our profile of this outlet
- Ocean Temperature Marks a New Absolute Record Pushed by El Niño: “We’ve Never Seen Anything Like It” (opens Eldiario.es in a new tab)
Eldiario.es — is Eldiario.es biased? Our profile of this outlet
- The Oceans Recorded a Record Average Temperature on Saturday (opens La Presse in a new tab)
- World's Oceans Record Warm at Unusual Time of Year (opens Aftonbladet in a new tab)
Aftonbladet — is Aftonbladet biased? Our profile of this outlet
Centre
9- Earth’s oceans reach a milestone scientists say may be unprecedented in millennia (opens Cleveland in a new tab)
- Earth’s oceans reach a milestone scientists say may be unprecedented in millennia (opens Staten Island Advance in a new tab)
Staten Island Advance — is Staten Island Advance biased? Our profile of this outlet
- EU Climate Service Copernicus: 21.1 Degrees - World Oceans Warmer than Ever (opens Tagesschau in a new tab)
Tagesschau — is Tagesschau biased? Our profile of this outlet
- Climate: the World's Oceans Have Recorded a New Average Daily Temperature Record (opens Sud Ouest in a new tab)
- Copernicus: World Seas as Warm as Never Before (opens wz.de in a new tab)
- On Saturday, the World's Oceans Recorded an Average Daily Temperature Record at 21.1°C. (opens France24 in a new tab)
- World's oceans hit hottest temperature ever recorded in August (opens Euronews in a new tab)
- The Temperature of the Oceans Reaches an Absolute Record: an Alarming New Signal of Global Warming (opens La Libre in a new tab)
Right
8- Ocean Temperature Recorded an Absolute Record of 21.1 oC on Saturday, According to Copernicus. (opens Sapo in a new tab)
- Ocean Temperature in 2026 Is the Highest Already Recorded, Points to EU Climate Change Service (opens Globo in a new tab)
- Ocean Temperature Recorded Absolute Record of 21.1 oC on Saturday (opens Observador in a new tab)
Observador — is Observador biased? Our profile of this outlet
- Sea Temperatures as High as Never Before (opens n-tv in a new tab)
n-tv
- World Seas at Record High: Copernicus Measures 21.1 Degrees (opens Frankfurter Allgemeine in a new tab)
Frankfurter Allgemeine — is Frankfurter Allgemeine biased? Our profile of this outlet
- The Temperature of the Sea Breaks Its World Historical Peak and Reaches 21.1oC (opens La Razón in a new tab)
- Global Sea Surface Temperature breaks record as El Nino gains strength (opens The Hindu Business Line in a new tab)
The Hindu Business Line — is The Hindu Business Line biased? Our profile of this outlet
- Global sea surface temperature hits record high of 21.1C: EU climate agency (opens Anadolu Ajansı in a new tab)
Anadolu Ajansı — is Anadolu Ajansı biased? Our profile of this outlet
Not rated
31- World Ocean Warms to Record 21.1°C: Scientists Warn of Threat to Planet (opens Gazeta.ua in a new tab)
- Sea and Ocean Temperatures Are at Their Highest Point in History. The Effects Will Also Reach Poland. (opens Rzeczpospolita in a new tab)
Rzeczpospolita — is Rzeczpospolita biased? Our profile of this outlet
- The Average Daily Temperature of the Sea Surface Records a New Record of 21.1 Degrees Celsius (opens El Economista in a new tab)
El Economista — is El Economista biased? Our profile of this outlet
- Climate Warming: the Oceans Reach an Absolute Record at 21.1°C (opens Stéphane Larue in a new tab)
Stéphane Larue — is Stéphane Larue biased? Our profile of this outlet
- The Oceans Have Reached a Record Temperature This Weekend (opens cnews.fr in a new tab)
- Copernicus Warns Viru Risks: Mierer Uechter d'Welt Esou Waarm Wéi Nach Ni (opens rtl.lu in a new tab)
- The Oceans Have Reached Their Highest Temperature (opens Le Grand Continent in a new tab)
Le Grand Continent — is Le Grand Continent biased? Our profile of this outlet
- EL NIÑO INFLUENCE ⟩ New Record Surface Temperature Measured in the World's Oceans (opens pmo.ee in a new tab)
Show 23 more
- Sea Temperatures as High as Never Before Since the Beginning of the Measurement (opens Moneycab in a new tab)
- Climate Change: the Temperature of the Oceans Broke a New Record This Summer (opens Radio France in a new tab)
Radio France — is Radio France biased? Our profile of this outlet
- Oceans: Water Temperature Reaches a Record 21.1°C (opens RTS in a new tab)
- Ocean Temperature Recorded Absolute Record of 21.1 oC on Saturday (opens IOL Portugal in a new tab)
IOL Portugal — is IOL Portugal biased? Our profile of this outlet
- The Water in the Oceans Has Warmed to Record Levels. (opens tvrain.tv in a new tab)
- The Average Temperature at the Surface of the Oceans Has Just Broken a New Record (opens Reporterre, le quotidien de l'écologie… in a new tab)
- Ocean Temperature Recorded Absolute Record of 21.1 oC on Saturday (opens O Minho in a new tab)
- Copernicus: World Seas as Warm as Never Before (opens onetz.de in a new tab)
- On Saturday, the World's Oceans Recorded an Average Daily Temperature Record at 21.1°C. (opens MARINE & OCÉANS in a new tab)
MARINE & OCÉANS — is MARINE & OCÉANS biased? Our profile of this outlet
- Oceans Overheated, an Absolute Record that Worries (opens Le Singulier in a new tab)
Le Singulier — is Le Singulier biased? Our profile of this outlet
- World's Oceans Are the Warmest in History, Risks Are Rising. One Thing Surprised Scientists (opens iDNES.cz in a new tab)
- Oceans Never Warmer - Record Measured in August Fuels Flooding and Devastating Storms (opens n1info.rs in a new tab)
- The World's Oceans Have Never Been Warmer (opens Vísir in a new tab)
- Ocean Temperature Recorded Absolute Record of 21.1 oC on Saturday (opens Noticias ao Minuto in a new tab)
Noticias ao Minuto — is Noticias ao Minuto biased? Our profile of this outlet
- Oceans Hit a New Temperature Record at an Average of 21.1oC (opens SIC Notícias in a new tab)
SIC Notícias — is SIC Notícias biased? Our profile of this outlet
- On Saturday, the World's Oceans Recorded an Average Daily Temperature Record at 21.1°C. (opens LaProvence.com in a new tab)
LaProvence.com — is LaProvence.com biased? Our profile of this outlet
- Ocean Temperature Marks a New Absolute Record Pushed by El Niño: “We’ve Never Seen Anything Like It” (opens elDiarioAR in a new tab)
elDiarioAR — is elDiarioAR biased? Our profile of this outlet
- Ocean Surface Temperature Hits New Record in Mid-August (opens Publico in a new tab)
- With El Niño, Oceans Have the Hottest Day of History - 24/08/2026 - Environment (opens Folha de S.Paulo in a new tab)
Folha de S.Paulo — is Folha de S.Paulo biased? Our profile of this outlet
- The Maximum Daily Temperature of the Sea Reaches a New Record: 21.1 °C on August 22 (opens efeverde.com in a new tab)
efeverde.com — is efeverde.com biased? Our profile of this outlet
- Copernicus: World Seas as Warm as Never Before (opens inFranken.de in a new tab)
inFranken.de — is inFranken.de biased? Our profile of this outlet
- Ocean Temperature Record Raises Fresh Fisheries Concerns - International Fishing News - The Fishing Daily - Irish, UK and European Fishing Industry News (opens The Fishing Daily in a new tab)
The Fishing Daily
- World's Oceans Are the Warmest on Record. The Consequences Are Already Visible, Scientists Say (opens Hospodárske Noviny in a new tab)
Hospodárske Noviny — is Hospodárske Noviny biased? Our profile of this outlet
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