An international group of scientists has recorded a record increase in seawater temperature due to climate change. This is reported in a paper published in Advances in Atmospheric Sciences.

According to the authors of the study, 2022 broke the record of 2021 for the increase in the temperature of the world’s oceans. The content of thermal energy dissipated in a two-kilometer-thick layer of seawater increased by an average of 10 zettajoules (1 zettajoule equals 10 to the 21 joules), which is about 100 times the total amount of electricity produced in 2021. The reason was the warming of the Earth due to anthropogenic carbon emissions.

Among the seven regions, four basins (North Pacific, North Atlantic, Mediterranean and Southern Oceans) recorded the highest levels of ocean heat since the 1950s. The researchers also found a record increase in contrast in salinity, as the saltwater became more salty and the freshwater fresher. This indicates the strengthening of the global hydrological cycle.

According to the scientists, the results of the study show that significant changes in the stability of ocean systems may occur faster than expected. Thus, increasing the temperature and salinity of seawater increases stratification as the seawater column separates into immiscible layers. This in turn affects the global cycles of heat, oxygen and carbon between the ocean and the atmosphere, increasing the ocean’s oxygen loss. Deoxygenation poses a threat not only to marine life, but also to terrestrial ecosystems and humans.