Thermohaline circulation
Thermohaline circulation (THC) is the global-scale component of ocean circulation driven by density gradients set by seawater temperature and salinity. It links surface and deep layers through high‑latitude sinking and widespread upwelling, transporting heat, freshwater, nutrients, and carbon and shaping regional and global climate. Modern observing arrays and paleoclimate evidence show its variability across years to millennia, with a very likely weakening projected under continued warming.
