Reacción a "The heat stored in the oceans has reached its highest level, according to the latest Copernicus report"

The value of this tenth edition of the Copernicus Ocean State Report (OSR10) lies not only in documenting an ocean undergoing change, but also in demonstrating how much our ability to interpret those changes improves when we have sustained observations and different ways of measuring them. The transition from knowledge to action is, in fact, one of the report’s central themes. But translating this into decision-making requires taking into account the differences across scales, locations and types of risk: a global or regional trend does not, in itself, determine how its consequences will play out on a specific coastline.

Global trends indicate the direction in which the ocean is changing; risk is often determined at a local scale. The Mediterranean illustrates this clearly. Sea-level rise is neither uniform nor linear: the western Mediterranean has seen an acceleration since the start of this century, whilst the eastern Mediterranean has shown a more variable trajectory and a recent acceleration; furthermore, local trends may temporarily deviate from the basin-wide trend. Storm Louis provides further evidence of this. Langosteira and Tarragona both exceeded their historical 99th percentile thresholds for wind and wave heights, but the impacts differed: in Langosteira the episode was more prolonged, lasting some 33 hours, whilst Tarragona experienced a shorter but more intense period. The orientation of the ports and the configuration of their breakwaters account for much of this difference. The same extreme event does not necessarily pose the same risk when local conditions change.

In this regard, the factsheet entitled ‘Spain’ should be read as an example of knowledge in action, not as a representative summary of everything the report itself reveals about the ocean surrounding Spain. The OSR10 also contains an improved indicator of surface temperature extremes for the Iberian Peninsula–Bay of Biscay–Ireland region, which combines various observational products and explicitly incorporates their uncertainty; it also analyses local sea-level trends in Barcelona, Ibiza, Mallorca and Melilla. Furthermore, in the Mediterranean context, it records an increase in the number of marine heatwave days, with 2024 seeing the highest number of such days in the last two decades and an average temperature 1.23 °C above the 1982–2024 reference period.

Therefore, one of the report’s most useful lessons for adaptation is that translating ocean knowledge into decisions is not simply a matter of filtering a global signal down to the local level. It requires linking broad trends to observations, infrastructure and conditions specific to each location. Ocean change may be global; the way in which it translates into risk — and many of the decisions needed to address it — is necessarily regional and local.