“Using a container ship, we have studied, not a specific point in the ocean, but a whole region, which goes from the Canary Islands to the Strait of Gibraltar, passing through the entire East Atlantic area. During two years of study, we have characterized the seasonal variability with high resolution, how the system changes between summer and winter, and what processes this change controls, ”said Professor González Dávila.
In the study, in which the researchers from Marine Chemistry participate, David Curbelo Hernandez, Melchor González Dávila, Aridane G. González, David Gonzalez Santana Y Magdalena Santana Casiano, it has been possible to measure the seasonal evolution over two years. “It has been seen that in winter, with colder waters, more CO2 dissolves, its content remains in the water and the pressure is lower. But in the summer, with the rise in temperatures, more carbon dioxide is released and in the system it acts as a source of CO2 towards the planet ».
The results obtained so far confirm that, from the point of view of the terrestrial system, the ocean acts as a CO2 sink at these latitudes, to which not only the temperature of the water contributes, but also the biological activity of the outcrop African, the high productivity of this region that sequesters carbon dioxide. To see the real evolution over the next few years, it is necessary to expand this project, at least five more years. “With two years of data it is impossible to obtain an optimal trend, because each year the climate is different, and one can be warmer than others. The general trend is to increase the ocean temperature as has been observed and the CO2 content, but what we want to know is, over the years, how this system is evolving, if it maintains the trends that are observed in other regions, or this region, being in the area close to the North African outcrop, behaves with more or less intensity. We will be able to know this evolution of the system over four or five years, ”said Melchor González Dávila.
The investigation, on board a container ship, also covers the Mediterranean
This work, the results of which have been published in the international journal Science of The Total Environment, has been carried out within the framework of the public-private agreement CanBIO, between the Government of the Canary Islands and the Loro Parque Foundation, and is part of the Carbon Dioxide and Ocean Acidification System Observations Network (Carbocan), within the Integrated Carbon Observations System (ICOS).
The observations have been made possible thanks to the collaboration with the Renate P (Nisa Marítima) ship, and the study also covers the area of the Strait of Gibraltar and the Mediterranean. «We have published what there is from the Canary Islands to the entrance of the Strait. It is the first study to be carried out in such a wide region and, above all, with such high resolution. Now we are collecting data in the Strait and then we will continue to Barcelona, because we do the observation line through this container ship that works from the Canary Islands to Barcelona. In this way we will be able to check three totally different systems: the Atlantic, the Strait and the Mediterranean. In two or three years we will publish how the evolution and trend have been, “concluded the Iocag researcher.