How does the sea change? Oceanographers discuss at Ca’ Foscari

Acidification, pollution, and changes in the flow of nutrients are just some of the changes taking place in marine environments, caused by both the climate and human activities. Understanding all of the interactive factors at play is one of the most complex puzzles for scientists. Climatologists, ecologists, oceanographers and meteorologists will meet at Ca’ Foscari on the 23rd - 25th of November to discuss the state and the prospects of research in this area. The promoters of the workshop, Themes 2016, are Angelo Rubino and David Zanchettin, oceanographers and climatologists at the Department of Environmental Sciences, Informatics and Statistics of Ca’ Foscari.

Professor Rubino, what are the unresolved questions in the study of the climate system?
Studying the climate means venturing into an intricate maze of high complexity: microscopic phenomena of short duration can crucially affect slow and global phenomena and vice versa. Because of this, we cannot say that there are questions that have been given a complete answer. It makes more sense to speak instead of "current questions", ie, questions that are important, at this time, within the relevant scientific community or, more generally, within society.

In this sense, the most significant unresolved question seems to me that of "attribution": what causes are attributable to the different cycles of climatic variability observed. An answer to this question would allow the quantification of the anthropic component in an even more precise way and contribute to reducing current uncertainty about the prediction of the state of future climates.

But, of course, the unsolved questions of great scientific and social value are numerous and range from the ability to predict interannual climatic fluctuations to the deep understanding of the mechanisms that contribute to the transition from one climate regime to another.

Why is it important to understand what happens in the deep sea?
The average ocean depth is approximately 4000 meters. In the "economy" of the climate system, the ocean is the "historical memory" of the forced and internal fluctuations: imbalances in the radioactive planetary balance, for example, help determine the heat content of the ocean. This can only be accurately determined if you carefully consider the changes occurring in the depths of an ocean. Ocean depths also take the slow path of dense waters, formed in the polar regions, which helps to maintain a stable stratification of the water.

What is the contribution of Ca’ Foscari University in the study of physics of oceans and the climate?
Several researchers at our university contribute to the understanding of oceans and climate. My group is interested specifically in the dynamic between oceans and the atmosphere; the role of the abyssal depths in determining ocean circulation, the impact of volcanic eruptions on the surface temperature distribution, or the causes of the profound secular climatic changes of the last millennia. Our approach studying this complexity is based on the analysis of experimental data, on the numerical simulation of the climate system and can essentially be classified as a multidisciplinary approach involving physicians, statisticians, biologists and so on.