Global Ocean Stratification & Thermohaline Circulation Collapse

The acceleration of ocean stratification represents one of the most significant and irreversible geophysical shifts documented since the late Paleogene period. As anthropogenic heat absorption increases the thermal gradient between surface waters and deep abyssal currents, the fundamental physical process of oceanic mixing is diminishing globally. This increased density layering—the separation of water masses by temperature and salinity—is critically compromising the Meridional Overturning Circulation (MOC), a global conveyor belt that dictates planetary heat distribution and nutrient cycling over vast timescales. The subsequent weakening or outright collapse of the MOC constitutes an inevitable physical constraint on global climate stability, fundamentally altering established biogeochemical cycles.