Thermohaline circulation estimates of the thermohaline circulation or, more accurately, the meridional overturning circulation. The deep water masses that participate in the MOC have chemical, temperature and isotopic ratio signatures and can be traced, their flow rate calculated, and their age determined. These include Pa / Th ratios. The Gulf Stream, together with its northern extension towards Europe, the North Atlantic Drift, is a powerful, warm, and swift Atlantic ocean current that originates at the tip of Florida, and follows the eastern coastlines of the United States and Newfoundland before crossing the Atlantic Ocean. The process of western intensification causes the Gulf
North Atlantic Deep Water waters mass of NADW form from overflow of the Greenland-Iceland-Scotland Ridge. They are Iceland-Scotland Overflow Water (ISOW) and Denmark Strait Overflow Water (DSOW). The overflows are a combination of dense Arctic Ocean water (18%), modified Atlantic water (32%), and intermediate water from the Nordic seas (20%), that entrain and mix with other water masses (contributing 30%) as they flow over the Greenland-Iceland-Scotland Ridge. The formation of both of these waters involves the conversion of warm salty northward flowing surface waters to cold dense deep waters behind the Greenland-Iceland-Scotland Ridge. Water flow from the North Atlantic current enters the Arctic Ocean