The variability of streams in the atmosphere and the ocean, as shown in a number of studies, affects the change in the speed of the Earth’s rotation. However, it can cause a reverse reaction—a change in the Coriolis force; as a result of this, atmospheric and oceanic streams can have some variability. In the following work, a hypothesis is presented and considered: it suggests that a change in the volume of Atlantic water inflow into the Barents Sea is related to the change in the Earth’s rotation speed. The paper presents a methodology for determining representative values of the temperature and salinity of seawater that describe the largest possible volume of the sea, as well as a methodology for calculating the content of Atlantic, river and melt water for the period of 100 years. The change of these parameters, and the length of day values, demonstrates the presence of both linear trends and cyclical fluctuations with a period of about 80 years. As a result, it was shown that a decrease in the Earth’s rotation speed with a linear trend somewhat decreases the observed intensity of the processes of global climate change in the Arctic region (an increase in temperature and salinity). Due to the summation of positive anomalies, both a linear trend and a quasi-80-year cycle, the modern period is characterized by abnormally high values of water temperature, the growth of which has not stopped and will possibly reach its maximum between 2025 and 2030.