After completing the SWOT-grid, R/V Bilim-2 conducted the rest of the sampling stations in Marmara Sea, and moved on to the Black Sea.
The SWOT fast sampling track also passes through south-western Black Sea, a dynamic area due to complex topography and injection of Mediterranean (through Bosphorus Strait) waters. Satellite SST and Chl-a images were investigated prior to the cruise, which showed meandering of the boundary current (i.e., Rim Current), and associated eddies and filaments in the area. SWOT sampling grid consisted of ~5km apart (Total of 40) CTD stations, just north of a well-known marine canyon (Sakarya canyon). The grid was put on the approximated seasonal path of the boundary current, following merged altimetry maps (Figure 2).
Black Sea, notorious for its rough conditions was in its top form during the cruise. Black Sea SWOT stations were completed in choppy conditions, and completed between 1 June 2023 14:55 – 2 June 15:50 GMT. Upon completing the SWOT stations, weather conditions worsened and R/V Bilim-2 returned to the harbor, where it stayed for ~3 days. After the storm, R/V Bilim-2 continued eastward to conduct sampling in the eastern Black Sea, for the BRIDGE-BS project (https://bridgeblacksea.org/ ).
Satellite SST and Chl-a images (Figure 3) confirm fine-scale gradients, which correspond to the outer periphery of an anticyclonic eddy, often referred to as the “Sakarya Eddy” (named after the canyon).
In-situ data processing is still on-going.