Title : Changes in oxygen saturation of the barents sea waters over the past 70 years: Relationships with climate, currents and commercial fish stocks
Abstract:
The main task of chemical oceanography is the study of spatial and temporal changes in the chemical composition of sea water in connection with physical, biological and other processes. Typically, the attention of researchers is focused on highly productive areas of the World Ocean, such as the Barents Sea shelf, since it is here that chemical processes develop most intensively and have the greatest practical significance.
Long-term changes in the background level of Barents Sea water oxygen saturation for the period from 1957 to the present were studied primarily on the basis of the results of annual expeditionary monitoring at the standard oceanographic section “Kola Meridian”. The Barents Sea is well aerated with oxygen. With the average long-term oxygen saturation of bottom water layers being 92.5% of the equilibrium value, the maximum range of changes is 9.6%. Oxygen saturation of bottom waters has decreased by 1-3% over the past 60 years, mainly during the period of climate warming. Despite relatively small changes in seawater aeration, it characterizes large-scale changes in the Barents Sea ecosystem and is a key element in models predicting the recruitment of important commercial species, such as cod and capelin.
The report presents an analysis of the dynamics of seawater aeration in the Barents Sea in relation to current climate changes. Special attention will be paid to how minor, far from physiologically significant changes in the oxygen saturation of seawater are characteristic of significant changes in the largest populations of marine fish in the World Ocean.
Audience Take Away:
- Changes in the Earth's climate and their consequences for humans are one of the key problems of interest to modern science. Using the Barents Sea as an example, we will show that the influence of climate on physical and biological processes leads to changes in the chemical state of the marine environment that have not previously been discussed in the scientific community. This can be used by scientists studying global climate and chemical processes. The practical application of the information presented in the report is the ability to make long-term (up to 3 years in advance) forecasts of the state of commercial fish populations, the catch of which affects the economy and food security of large regions of the Earth. Mathematical approaches to predicting the state of commercial fish populations using data on the chemical state of sea water have significantly improved the accuracy of commercial forecasts. These approaches have only begun to be put into practice in the last ten years and only for the Barents Sea. This direction is currently being developed. Accordingly, the innovative ideas presented in the report can be adapted to study other World Ocean areas.
