Аннотация:To clarify the role of thermohaline factors in the formation of climatic trends in the North Atlantic (NA) thermohaline circulation, the contributions of changes in potential temperature and salinity to trends of the streamfunction of the Atlantic Meridional Overturning Circulation (AMOC) were determined. To do this, using the INMOM (Institute of Numerical Mathematics Ocean Model) and data of the EN4 electronic atlas (MetOffice, United Kingdom), the NA circulation was reconstructed by the diagnosis–adjustment method for the characteristic periods of 1951–2017, 1951–1990, and 1991–2017. In two selected periods of 1951–2017 and 1951–1990, all the main features of changes in the AMOC are explained mainly by temperature changes, which prevail over changes in salinity. At the same time, the observed trend towards weakening of the main core of the AMOC streamfunction from 1991 to 2017 is caused by changes in salinity, and the strengthening of the main core of the AMOC streamfunction from 1951 to 1990 is caused by changes in potential temperature. A relationship has been found between the trends of the AMOC streamfunction maximum at 38.5◦ N and differences between zonally-averaged sea levels at 34.5◦ N and 57.5◦ N, which can possibly be used as the variability index of the AMOC streamfunction.
