New Insight in the Determination of Thermodynamic Equilibrium Thickness Using Heat Budget over Barents Sea

This paper examines various atmospheric and sea ice data to understand the Barents Sea's small-scale energy balance. The ERA-5 reanalysis products are used to calculate the atmospheric budget. Seasonal cycles detected using ocean-atmosphere interactions show that potential energy is substantially higher than kinetic energy over the Barents Sea, which is one of the reasons for it being colder than other places. The month of June experiences maximum radiation at the top of the atmosphere with a value of 16.19 Wm^-2 and December experiences minimum with a value of 0.11 Wm^-2. However, the heat flow at the surface is the highest during December with values ranging between 0.64 Wm^-2 and 0.69 Wm^-2. The system is constrained by declining solar flux, increasing heat flux at the Earth's surface, and atmospheric transport. Sea ice minimum and maximum months in the Barents Sea exactly coincide with those of the Arctic Sea. However, Barents Sea ice thickness is only limited to 3.5 m, but for the Arctic it is seen extending up to 4.5 m. Additionally, the area has recently experienced a massive exchange of heat (energy) between the ocean and the atmosphere, which is believed to be due to Atlantification, which is a well-known process. The Barents Sea is the region where the process of Atlantification is first observed. A new method has been developed to estimate the Thermodynamic Equilibrium Thickness (TET) of the sea. TET is calculated using a thresholding technique that is applied to total thermal radiation. The approach adopted for TET extraction is important as it generates several important fluxes, including the energy flux between the ocean surface and the atmosphere above it.