Figure 14: Schematic of four factors which are believed to be primarily
responsible for multi-decadal variations of the strength of the
Atlantic thermohaline circulation. These are (A) the rate of
Atlantic Ocean evaporation, (B) the rate of ice flow (eg., ice
thickness) into the North Atlantic from the Arctic Ocean, (C) the
rate of influx of warm saline water to Atlantic from the Indian
Ocean, and (D) the rate of influx of relatively cold and fresh water
from the South circumpolar currents. High values of processes (A)
and (C) enhance the conveyor circulation, high values of processes
(B) and (D) inhibit it.