Current State of the Cold Intermediate Layer of the Black Sea Waters from Ship Measurements 2022–2025

The article studies the state of the cold intermediate layer of Black Sea waters and its transformation over the period 2022–2025. The data of hydrological measurements obtained during expeditions of the R/V Professor Vodyanitsky in the northern and northeastern Black Sea from 2022 to 2025 were used. Vertical water temperature and density profiles at stations with a sounding depth of more than 400 m were considered. Isopycnically averaged water temperature profiles for each expedition were obtained. It is shown that the warming trend of the waters of the cold intermediate layer persists, despite its significant replenishment in 2022. In addition, this trend extends to the underlying layers. In 2024, there is a unique situation of the absence of a cold intermediate layer in the upper part of the main/permanent pycnocline and the presence of a layer with minimum temperatures in the lower part of the main pycnocline. Also, since 2024, there has been a threefold increase in the rate of increase in water temperature in the layer between the 15.6–16.6 kg/m3 isopycnals, i.e., in a layer unaffected by seasonal variability.