How do oceans regulate Earth's climate?

Oceans stabilize climate through their vast heat and carbon storage. Water has high heat capacity, so oceans absorb about 90% of excess heat from greenhouse warming. This thermal inertia buffers temperature swings. Oceans also circulate heat via currents (e.g. Gulf Stream moves warm equatorial water to higher latitudes). Moreover, oceans take up ~30% of anthropogenic CO₂, sequestering carbon in dissolved form or biological processes and slowing atmospheric warming. In sum, oceans act as a heat sink and carbon sink, redistributing energy and reducing climate extremes.