Mikal Schlosser

What Knowledge Do We Lack About the Ocean?

Environment and pollution Marine research

The UN has declared the 2020s a ‘Decade of Ocean Science for Sustainable Development’. Why is this necessary and what important knowledge do we lack about the ocean? Colin Stedmon provides the answer. He is a Professor at DTU Aqua and head of the Danish Center for Marine Research.

Why increased focus on the ocean?

The UN’s Decade of Ocean Science emphasizes that humanity depends on the ocean, which we use as a means of transport, for tourism and recreation, and as a source of both energy and food products. It is crucial that we ensure a sustainable development here as well. Even those who live far from the ocean are dependent on it, as it plays a major role in our climate and weather development.

Has the ocean been overlooked as a research area?

No, I do not think so. But we are lagging behind in forming a picture of the global system. Even though satellites have been of huge importance, they only measure the upper metres of the ocean—and as the ocean is four kilometres deep on average—satellite measurements are not enough. The challenge is that water is a difficult medium to work with. It is difficult to see through, and it is difficult to measure through, as many signals from, for example, probes cannot penetrate water. The ocean can be a rough environment, and the pressure is very high at depths. Overall, this makes great demands on the technological solutions we need. Man has mapped the surface of the Moon, but we have mapped very little of the Earth’s seabed. We have had people on the Moon, but no one has stood on the bottom of the deepest place of the ocean. Just as space technology has paved the way for usable solutions in everyday life on Earth, I am pretty sure that technological innovation for exploration of the ocean can also be used for other purposes—for example industrial processes—where one needs sensors that can cope with tough conditions.

What knowledge is especially lacking?

The further we get out on the open ocean, the less we know. We have quite good knowledge of coastal areas—at least in our part of the world—because they are easily accessible, and we can sail out almost daily and make measurements and observations. So we have reasonably good insight into the processes in these areas and the human impact here. But on the open ocean, we lack a fundamental understanding of marine processes, in terms of physics, chemistry, and biology. We also do not fully understand how the ocean interacts with climate and weather, and how climate change affects water circulation, water properties, as well as sea currents, and sea circulation. It is not completely unknown territory, but there are many uncertainties in our understanding of these things.

Why is more knowledge important?

With a deeper understanding of the ocean, we can better prepare for the consequences of climate change, which, for example, leads to changes in sea currents due to global warming and increased supply of meltwater, reduction of the ability of the ocean to capture and store carbon, changes in marine biodiversity, and much more. We become better at predicting events and avoiding unforeseen situations, be they extreme weather, tidal waves, failed harvests, or migrating fish stocks. We will go from responding to crises we did not see coming to being able to navigate them. We can make smoother adaptations, and we can avoid conflicts between countries. More knowledge will also ensure that our exploitation of the ocean becomes more sustainable, and we can also better follow fish stocks that have begun to migrate due to climate change. In fact, the fish do not care about what quota agreements we have entered into on land.

What can Denmark contribute with in the Ocean Decade?

We have a strong marine research environment in Denmark and we can continue our good work and collaboration, decade or not. But the UN’s Decade of Ocean Science requires more than oceanographers. When you look at the UN's goals for the Ocean Decade and the research needed (see fact box), it is clear that many academic and specialist environments can play a role in the decade. We are good at interdisciplinary collaboration in Denmark, and here I think we can make special contributions to the decade.