RV "Akademik Tryoshnikov" left Arkhangelsk on August, 17 2018 and on August 22-30, observations in the western part of the Laptev Sea under the auspice of CATS (The Changing Arctic Transpolar System)/Transdrift program were carried out. 42 CTD stations were made.Conductivity, Temperature, and Depth (CTD) profiles of the water column were taken by using a Seabird SBE911plus CTD system. This system measures conductivity, temperature, and pressure at a 24Hz sample rate. Pressure was measured by a Digiquartz® sensor with accuracy of ±0.015% of full-scale range. For temperature measurements an SBE 3T sensor was used with accuracy of 0.005°C. Conductivity was measured by an SBE 4C sensor with accuracy of 0.0003 S/m.All Seabird sensors had been returned to the manufacturer after the 2015 expedition for servicing and calibration, and stored unused since then.This study was supported by the Russian Ministry of Science and Higher Education, project: RFMEFI61617X0076.