evidence: The world’s oceans form a primary component of the climate system. They contribute to climate regulation by absorbing carbon dioxide (CO2) emissions and heat. They have absorbed over a quarter of human-caused CO2 and around 90% of the excess heat produced in recent decades. The oceans are by far the largest active carbon reservoir on the planet, storing about 38,000 billion tonnes of carbon. They are also a crucial source of food supply and livelihoods for billions of people. [...] Warmer ocean surface temperatures also affect weather patterns, shifting rainfall and causing some regions to experience flooding while exacerbating drought and wildfire risk in others. The oceans move water around the planet, driving evaporation and precipitation cycles. The warmer surface temperatures increase evaporation, producing more water vapour which feeds rainstorms and blizzards. Research has also linked ‘landfalling droughts’ – droughts that start over oceans and that migrate over months onto land – in the Western United States with weather patterns over the Pacific that are changing in a warming world. [...] Ocean warming disrupts the carbon cycle: for instance, as waters in the high latitudes (close to the poles) warm, the oceans’ solubility power decreases, which reduces the amount of carbon that can be absorbed and eventually sequestered.