El BBVA Foundation Frontiers of Knowledge Award in Climate Change and Environmental Science The award has been given to the American oceanographer Carl Wunsch, from the Massachusetts Institute of Technology (MIT), for having succeeded in making the ocean cease to be the great blind spot of climate change and become a measurable component of the global climate system.
With a career that began in the sixties, Wunsch has been key in demonstrating that The ocean is a central regulator of Earth's climate.and that its accelerated warming explains a good part of the Rising sea levelsThe loss of ice at the poles and the intensification of extreme weather events that are already being felt strongly in Europe and, very visibly, in the Iberian Peninsula.
A pioneer in measuring ocean warming
Initially trained in Mathematics and with a doctorate in Geophysics, Carl Wunsch understood very early on that without solid ocean data It was impossible to predict how the climate would evolve. In the 1970s, he participated in a report by the U.S. National Academy of Sciences on the impact of increased CO2 on the planet, and, as he recalls, oceanographers at the time had little to contribute: it was unknown. how much energy and how much carbon did the sea actually absorb?.
This realization led him to conclude that oceanography needed “a radically different approach”Traditional observation, based almost exclusively on ship-based expeditions, was slow, extremely expensive, and, in practice, incapable of tracking the rapid changes in the climate system. It was impossible to keep a ship in the same spot for weeks to observe how temperature or salinity evolved; by the time an expedition ended, the ocean had already changed.
From there, Wunsch began working closely with engineers to take advantage of available technological advancements. The emergence of satellites and the increase in computing power They opened the door to a new way of investigating: observing the ocean almost daily from space and complementing it with autonomous instruments spread throughout all the seas.
The Frontiers Prize jury emphasizes that thanks to these efforts The increase in ocean temperature has been accurately quantified and the accumulation of thermal energy associated with greenhouse gas emissions. This extra energy is what is driving sea level rise and amplifying the risk of heat waves, droughts, floods, and torrential rain events.
Transforming oceanography with large-scale global experiments
One of the milestones that the jury highlights most is the World Ocean Circulation Experiment (WOCE), initiated by Wunsch in 1990 within the World Climate Research Programme. Its objective was ambitious: to obtain, for the first time, a global view of the heat flows linked to ocean circulation and their variability in the context of global warming.
For twelve years, WOCE combined satellite observations with a network of buoys equipped with sensors They measured temperature, salinity, and other key parameters. This deployment, with the participation of nearly thirty countries, paid special attention to the Southern Ocean, a region critical to the global climate but, until then, very little sampled.
The data obtained have proven essential for adjust and validate climate models which are now used to project future scenarios. They have also allowed for a better understanding of how heat is redistributed within the ocean, how deep water masses are ventilated, and how the ocean, atmosphere, and ice sheets interact.
Wunsch insists that, with previous methods, covering the ocean on a global scale would have taken “a hundred years.” The combination of satellites, buoys, and advanced mathematical techniques made it possible, for the first time, to track the evolution of the sea on timescales compatible with the speed of current climate change.
All that work has changed the image of the ocean: from being seen almost as a slow and immutable geological structure, it has come to be recognized as a dynamic and turbulent systemas complex and changeable as the atmosphere, and with a direct influence on the regional climate of Europe and Spain.
Pioneering missions: from satellite altimetry to the Argo program
The definitive leap towards global and continuous observation came with the high-precision satellite altimetryUnder Wunsch's scientific leadership, the Franco-American TOPEX/Poseidon mission, launched in 1992, succeeded in measuring variations of just a few centimeters in the height of the sea surface from space. The evolution of altimetry has allowed the mapping of the planet's water in great detail.
It may seem like a minor detail, but those small differences in height hide key information: A warmer ocean is less dense and expands.so the elevation of the surface serves to infer changes in heat content. This relationship has allowed scientists to reconstruct how the ocean has warmed up in recent decades., validating with direct observations what could previously only be estimated with models.
The next piece of this surveillance system was the Argo programLaunched in 1998, it is an international network of nearly 4.000 autonomous buoys that drift and periodically dive to depths of up to 2.000 meters, measuring temperature, salinity, and currents.
These buoys send the collected information via satellite, allowing access to an updated map of the ocean interior virtually in real time. Argo remains fully operational and its data is one of the foundations of current estimates on the rate of ocean warming and sea level rise.
As the BBVA Foundation points out, the combination of satellite altimetry and direct depth measurements has revolutionized physical oceanography: it has gone from being a science based on specific campaigns to being based on a global, continuous and coordinated observation system, without which it would be impossible to understand the evolution of the climate today.
The ocean as a driver of extreme phenomena
The data collected by the systems that Wunsch has implemented show a clear trend: The ocean is warming at an ever-increasing rateabsorbing both heat and carbon dioxide. According to the World Meteorological Organization, in the last two decades the ocean has absorbed an amount of energy each year equivalent to about eighteen times the annual energy consumption of all humanity.
This enormous heat reserve has very concrete consequences. First, it translates into a global average sea level risewhich is already several centimeters above the levels recorded thirty years ago. Furthermore, warming waters promote the melting of ice in polar oceans and accelerate the melting of glaciers and ice sheets, further exacerbating sea level rise; the loss of ice in Antarctica It is one of the most relevant threats in this context.
The prize jury warns that this process does not only affect remote areas: European and Spanish coastal regions They face an increased risk of flooding, beach erosion and damage to coastal infrastructure, especially if polar ice melt accelerates in the coming decades.
Added to this is the ocean's role as "fuel" for extreme weather events. More heat in the sea means more energy available to fuel them. episodes of heavy rainfall, heat waves, or severe stormsIn the Iberian Peninsula, experts directly link this accumulation of oceanic energy to the proliferation of DANAs, those episodes of cold drops that leave torrential rains and that have become more frequent and damaging.
As Wunsch himself summarizes, the more carbon dioxide is added to the atmosphere, the more energetic the climate system becomes as a whole. And a more energy-charged system is, by definition, more prone to extreme behaviors and potentially abrupt changes, something that is especially worrying in the coming decades.
International cooperation and its impact on Europe and Spain
The Frontiers of Knowledge Award also underscores the role of international scientific cooperation Throughout Wunsch's career, programs such as WOCE, TOPEX/Poseidon, and Argo have required the collaboration of dozens of countries, coordinated scientific fleets, and agreements to share open data with the research community.
For Europe and Spain, this collaborative dimension is not a minor detail. European countries actively participate in the deployment and maintenance of ocean observation networksThey contribute with research vessels, satellites and data centers, and, at the same time, directly benefit from the information generated.
Without these systems, it would be much more difficult to improve. weather and climate predictions that affect the continent: from monitoring Atlantic storms that reach the western European coast to monitoring marine heatwaves in the Mediterranean, with impact on fishing, tourism and the coastal ecosystems.
The BBVA Foundation jury points out that climate is, in essence, a global phenomenon and that it is impossible to understand what is changing—or prepare for what is to come—without coordinated efforts between countriesThe awarding of the prize to Wunsch is thus interpreted as an explicit recognition of this way of working, based on the exchange of knowledge and data beyond borders.
In the European context, this information is integrated into initiatives such as Copernicus climate services or national and EU climate change adaptation strategies, which require reliable estimates on the sea level evolution, frequency of extreme events, and regional ocean warming to plan investments and public policies.
Taken together, the award given to Carl Wunsch highlights an idea that is increasingly accepted by the scientific community and European institutions: Without understanding how and how much the oceans are warming, it is impossible to predict the future of the climate.The global observation systems that he has helped to design have become a fundamental tool for assessing risks, designing adaptation strategies, and providing a solid foundation for making political and economic decisions in Spain, Europe, and the rest of the world.
