Further warming of ocean waters could cause a global "resettlement" of plankton from the tropics to the poles, according to a study published in the journal Science.
"In case of further warming of ocean biodiversity in the tropics could fall by 40% — mainly due to phytoplankton, which, most likely, will not have time to adapt and just move to cooler waters closer to the poles" — the authors of the article.
Warming waters, explains the study's authors, may limit the ability of microorganisms to grow and photosynthesize.
The researchers analyzed data from 1935 to 2011, exploring the ability of 130 species of phytoplankton to adapt to changes in water temperature. It was found that these organisms seem to tolerate colder temperature optimum (comfort range) than warm. Based on these results, the researchers concluded that the microorganisms prefer to move to higher latitudes with colder waters in the event of a further warming of the ocean.
Tropical species of plankton can already be found in the Arctic — the researchers believe that they are brought there by the warm currents that periodically arrive from the Atlantic to the Arctic Ocean. In recent decades, these warm "pulsating" flows have become more frequent, and further penetrate into the Arctic Ocean, as scientists say, global warming.
Earlier, U.S. researchers have shown, based on observations over the past 135 years, what is going global "warming" of the ocean. According to their calculations, the increase in temperature during this period was about 0.33 degrees Celsius at depths up to 7000 meters, and in the surface layer of water — up to 0.6 degrees.