First blank: warmer. Second blank: thermohaline. Third blank: colder.
The Pacific Ocean has warmer water than the Atlantic Ocean. Thermohaline circulation moves water between warmer and cooler, and saltier and less salty, areas of the ocean. If the thermohaline circulation stops due to global warming, Europe will likely become colder.
Thermohaline circulation is the current is deep ocean waters, where the density and the temperature of the water are different. The deep-ocean waters start in the polar regions of the earth where the water is extremely cold. Here, the water gets saltier due to the formation of sea ice.