canary islands ocean temperature record 2026

Canary Islands sea hits second-hottest year on record

Compiled with the help of artificial intelligence, based on Spanish-language information. Source below the article.

Second-hottest year on record for Canary Islands waters

The ocean surrounding the Canary Islands is recording the second-highest average temperature since records began this year. Figures from the Spanish Institute of Oceanography’s Ocean Observation System (IEOOS) show that the Canary Islands Marine Demarcation – the maritime area around the islands over which Spain exercises sovereignty – has reached daily temperature peaks close to 25.76C, the highest in the historical series, recorded in 2023.

IEOOS indicators reveal that ocean temperatures in the archipelago usually peak in August, September and October. 2026 began with values similar to the average, but in mid-June temperatures soared and, since then, have generally remained above those recorded since 1982, with the exception of 2023. This year’s maximum was reached on 29 September, with an average temperature of 25.54C.

A global phenomenon

These figures are not an isolated phenomenon. On a global scale, the average sea surface temperature (excluding the polar regions) reached 21.05C in September, the highest value recorded for that month since data began, according to the Copernicus Climate Change Service (C3S). The reading is 0.13C above the previous record for a September, set in 2023, when the average was 20.92C. Copernicus also notes that during that period there were record sea surface temperatures in large areas of the Atlantic and in the western Mediterranean.

A good deal of this overheating is due to El Niño, explains Pedro Vélez, a researcher at the Spanish Institute of Oceanography. It is a natural cyclical phenomenon that raises surface water temperatures in the tropical zones of the Pacific and alters rainfall patterns, which can cause droughts and floods, especially in the Americas. It occurs irregularly, generally every two to seven years, and usually lasts between nine and twelve months, reaching its peak between November and February. Its impact is now even greater because it is acting on a planet already overheated by climate change.

The World Meteorological Organization (WMO) warned in September that El Niño this year will be “very strong” and, indeed, the sea surface temperature in the Equatorial Pacific recorded a historic high of 29.7C that same month, according to Copernicus. Research by Climate Impact Lab, a research centre in Chicago (United States), estimates that the current phenomenon could cause 451,000 deaths related to extreme temperatures.

How El Niño changes the winds around the islands

In the Canary Islands, El Niño alters the wind regime. This is “the main mechanism” through which the phenomenon affects the rest of the planet, explains Vélez. It is what experts call the “teleconnection” of El Niño. With normal or strong wind, the sea is constantly churned. Surface water mixes with the deeper layers and is replaced by colder water, which helps to distribute heat. But when the wind drops, the uppermost layer of the ocean mixes less with the layers below and accumulates the solar radiation received over days, which raises its temperature.

This phenomenon adds to the progressive warming of the ocean around the Canary Islands, Vélez adds. Between 1982 and 1989, the average surface temperature was 20.92C; between 1990 and 1999, 21.07C; between 2000 and 2009, 21.33C; between 2010 and 2019, 21.41C; and between 2020 and 2026, 21.96C. According to IEOOS data, the current upward trend would mean an increase of 2.65C per century.

The researcher also mentions another factor that could recently be contributing to the rise in temperature: international regulations that reduced the maximum sulphur content permitted in ships’ fuel, from 3.5% to 0.5%. This has improved air quality on the one hand, but has also led to a sharp reduction in sulphur aerosol emissions, which affects cloud formation and produces a decrease in the albedo effect (the amount of sunlight reflected back into space), raising the ocean’s temperature. The fewer the clouds, the more solar radiation reaches the surface. “The impact of this phenomenon is seen more in the long term, so its consequences will be seen within ten years. But little by little it is being noticed,” concludes the researcher, who stresses the “complexity” of the system in making sense of these figures.

“Although this year the whole ocean is recording historic surface temperatures, the hurricane season in the Atlantic has not yet recorded a single one [the interview with Vélez was recorded days before the formation of Hurricane Isaías], something that has practically not happened since records began. What I mean is that the system is so complex that what we thought we had clear is sometimes not even that,” he concludes.

Devastating effects beneath the waves

The steady rise in ocean temperature also has multiple devastating effects underwater: mass fish migrations, changes in fishing, coral bleaching… Extreme heat means many species “can end up collapsing”, summarises Sara González-Delgado, a postdoctoral researcher at the University of Barcelona and a member of the Punta de Fuencaliente Marine Climate Change Observatory (OMACC).

The marine biologist explains that her group assessed the response of the starfish Coscinasterias tenuispina to gradual temperature increases. They observed that, as the water warmed, stress levels rose until reaching a critical point (around 30C sustained) at which the animal simply stopped breathing. A point of “no return”. “It is worrying that species reach their collapse threshold and cannot withstand current temperatures or those recorded in the future. And that they may die, of course,” she adds.

González-Delgado recalls that the Canary Islands has a subtropical ecosystem that brings together both species adapted to heat and others that are less so. Warming especially threatens the latter, whether endemic or native. One example is the yellow moss, typical of Tenerife. These algae form underwater forests that act as nurseries where larvae and juvenile fish take refuge and grow. And if we lose them, the expert emphasises, the impact on artisanal fishing and local shellfish gathering would be notable.

Another consequence worth bearing in mind is the expansion of invasive species favoured by the heat. Sometimes ships inadvertently transport tropical organisms that are normally confined to port areas because the water outside is too cold. However, when the sea temperature rises, these species can find the ideal conditions to colonise neighbouring coasts and islands. A recent case mentioned by the researcher: the red swimming crab Cronius ruber. Another “worrying” example: the alga Rugulopteryx, native to the north-west Pacific and whose spread in the archipelago is also linked to maritime traffic. “Suddenly this species of alga has appeared, which nobody eats because it is toxic, and it is replacing other algae that we have in the islands,” she stresses.

Resilience – but only up to a point

Despite the seriousness of the diagnosis, González-Delgado highlights the capacity for resistance and adaptation that her team has observed in Canarian marine fauna, specifically in some species of sea urchins and limpets. These animals can activate or deactivate certain genes in response to temperature changes, a mechanism that acts as a kind of buffer and allows certain populations to withstand warming or move to colder areas. Although everything has “a limit”.

“We always say that, for now, there are still species that can fight, that can hold on. But, if we carry on like this, they will end up disappearing and our ecosystems will change completely,” the expert concludes.

🧭 Explore the Canary Islands with us
📰 Read more Canary Islands news ☀️ Check Canary Islands weather 🏖️ Find the best beaches in the Canaries 📲 Join us on WhatsApp

Source

Scroll to Top