 The ACC and the global thermohaline circulation strongly influence regional and global climate as well as underwater biodiversity.Another factor that contributes to the climate of the subantarctic region, though to a much lesser extent than the thermohaline circulation, is the formation of Antarctic Bottom Water (ABW) by halothermal dynamics.The halothermal circulation is that portion of the global ocean circulation that is driven by global density gradients created by surface heat and evaporation.