In this month's ‘In Depth’ we talk to researcher Marta Umbert, an expert studying ocean currents and polar areas.
Marta Umbert, a physical oceanographer specialising in the study of the Arctic Ocean, has dedicated her career to improving the understanding of polar dynamics in the context of climate change. With a degree in Marine Sciences from the University of Cadiz and a master's degree in Oceanography and Coastal Management from the University of Barcelona, her career has been marked by prestigious grants such as a scholarship for a master's degree from the ‘la Caixa’ Foundation, or the Marie Skłodowska-Curie postdoctoral grants. She has also collaborated with international centres such as the French CNRS and IFREMER, as well as the University of Washington in Seattle (USA). She was recently awarded an ERC Starting Grant for her innovative project ‘FRESH-CARE’, which uses advanced remote sensing and artificial intelligence technologies to unravel changes in Arctic sea currents and freshwater. With a strong background in satellite data fusion and improved ocean salinity resolution, Marta is leading key research to better understand the impact of ice melt on the global climate system.
1. What led you to focus your career on the study of the Arctic and what were the first challenges you encountered when researching this remote region?
The polar areas are the most rapidly changing areas on the planet, but they have been difficult to access and often neglected due to their remoteness and the cost of accessing them. I believe that the scientific community must now focus on better understanding these regions and how they are connected to the global climate. These are the areas of the planet with the least in situ data and therefore where there are currently the most uncertainties. I work with satellite data, which is a great opportunity to better understand what is happening in these areas. However, one of the main challenges is that for much of the year they are covered by ice, which makes it difficult to obtain satellite data.
2. You have recently received an ERC Starting Grant for your project ‘FRESH-CARE’. Could you explain how remote sensing and artificial intelligence could revolutionise the study of ocean currents and freshwater in the Arctic?
The fact that there is less and less ice will allow satellites to capture more information than ever in these areas. There is currently a great deal of interest from space agencies in developing satellites specifically designed for polar areas, which we will be able to use to study currents and freshwater flows. In addition, new artificial intelligence techniques can be applied for the first time in the Arctic to go beyond the knowledge of the ocean surface provided by satellites and also reconstruct what is happening deep in the Arctic Ocean.
The Arctic is warming rapidly, causing significant hydrographic changes such as sea ice retreat, freshwater accumulation and altered ocean currents, which can destabilise the Earth's thermohaline circulation. Despite its key role in the global climate system, the ultimate fate of Arctic freshwater remains uncertain. FRESH-CARE will provide pan-Arctic estimates of ocean currents and freshwater distribution at high spatial and temporal resolution, improving the understanding of freshwater fluxes, which are crucial for future global climate models and society at large.
3. Your research focuses on ocean currents and hydrographic changes in the Arctic. What impact do these phenomena have on the global climate system and why is it crucial to study them right now?
Hydrographic changes in the Arctic, including sea ice retreat, freshwater accumulation and altered ocean currents, have a profound impact on the global climate system. These phenomena intensify the stratification of water masses, which can destabilise the Earth's thermohaline circulation, a key component that regulates planetary heat transport. The Arctic is warming at a much faster rate than other regions, and these changes could have global consequences, such as altering weather and climate patterns.
Studying them now is crucial because the fate of Arctic freshwater remains one of the biggest uncertainties in current climate models. Improving our understanding of freshwater flows and ocean currents will allow us to make more accurate projections of future climate and anticipate its effects globally, helping both the scientific community and society to better prepare for these changes.
4. You have worked on integrating satellite data to improve the accuracy of melt estimates. What advantages does satellite technology offer over traditional numerical models in Arctic monitoring?
Numerical models are essential tools for understanding processes and making climate projections, but they need real data to be effective. Satellite technology offers a key advantage: it allows real-time, large-scale observations of what is happening in the Arctic, including ice cover, surface temperature and ocean current movements. These data are crucial for feeding up-to-date information into models, improving their accuracy and making them more realistic.
From 2024, the SWOT satellite will start providing extremely high-resolution sea-level products, especially at high latitudes, opening up new scientific opportunities for the study of the Arctic Ocean. In addition, the SMOS satellite's sea surface salinity (SSS) products for the Arctic are directly related to freshwater, allowing a better understanding of how it is evolving in the region and how it will continue to change over the next decade.
The integration of these data with artificial intelligence techniques will allow the calculation of ocean currents and freshwater fluxes in the Arctic at an unprecedented level of detail. Furthermore, the integration of these observational data allows for the validation, adjustment and refinement of numerical models, improving our understanding of the Arctic system and facilitating more reliable climate projections for the global climate system.
5. The results of your latest study show a significant reduction in the bias of freshwater estimates. How do you think these spreading can contribute to the fight against climate change?
The distribution of liquid freshwater content in the Arctic Ocean, integrating remotely sensed data of sea surface salinity in ice-free areas down to typical mixing depths, improves freshwater estimates compared to those based on numerical models alone. Such spreading is crucial in the fight against climate change, as it allows a better understanding of how freshwater is distributed in the Arctic and how it affects ocean circulation and the global climate system. Improving the accuracy of freshwater estimates is essential for adjusting climate models and more accurately projecting future climate change impacts, such as water stratification and possible effects on thermohaline circulation. This helps to develop more effective strategies to mitigate the effects of climate change and adapt climate policies to new environmental realities.
6. What are the main challenges facing polar research today, both scientifically and logistically?
The main challenges for polar research include the lack of in situ data, as many areas are difficult to access and often ice-covered, making it difficult to validate models. In addition, accelerated climate change causes rapid changes in the ecosystem, complicating observations.
Logistically, extreme conditions, high costs and access difficulties are major obstacles to expeditions. International collaboration is also essential, which can be difficult in managing complex projects.
7. Your work has ranged from model development to expeditions to Antarctica. How do these two facets of your research, the theoretical and the practical, complement each other in your day-to-day work?
It is essential not to lose sight of the reality of these areas to better understand the processes that occur. Expeditions provide vital data that improve the accuracy of theoretical models. Practice allows me to directly observe the phenomena and collect information that is then integrated into the models, improving their reliability and understanding of the polar system. This continuous interaction between theory and practice is key to advancing research.
8. The accumulation of freshwater in the Arctic has the potential to alter the thermohaline circulation. What risks does this pose to the global climate and how might regions further away from the Arctic be affected?
The accumulation of freshwater in the Arctic may destabilise the thermohaline circulation, a crucial system that regulates global climate. If this flow is disrupted, significant changes in weather patterns could occur, affecting distant regions such as Europe and North America. This could result in more extreme weather, such as colder winters or warmer summers, as well as changes in precipitation and storm intensity. In addition, these alterations could impact marine ecosystems and biodiversity, with consequences for global fisheries and food security.
9. You have led international research and worked with teams from all over the world. How important is global collaboration in Arctic research and how does it influence the spreading of knowledge about the Arctic?
Global collaboration is essential in Arctic research and in science in general. I am of the opinion that scientists must share our knowledge and work together to advance more effectively. Moreover, Spain does not have Arctic science bases, and research in this region needs state-of-the-art icebreaker ships to access them in situ. Working together with countries that do have such infrastructure is essential for effective expeditions.
International collaborative scientific efforts enable the sharing of data, technologies and knowledge, enriching research and improving its trustworthiness. Ultimately, collaboration not only accelerates the spreading of knowledge about the Arctic, but also benefits all scientific fields, especially those that affect us as globally as this one.
10. Finally, from your perspective as a polar researcher, what makes you dream of a better future for the oceans and what measures do you think are essential to protect these ecosystems in the context of climate change?
We are at a historic moment in which it is essential to mobilise social, political and economic actors to take courageous steps towards a green transition and a more mature socio-economic model that learns from the mistakes of the past and promotes less, more local and fairer consumption for all. These actions will allow us to live in harmony with the oceans, the planet and all other living things safely and sustainably.
For me, to dream of a better future is to do my small part by offering a better understanding and data that can demonstrate that these courageous measures are urgent and vital. I also like to practice a way of working that is collaborative, listening and caring in my work and social environment, which I hope can inspire others, both older and younger generations.