A study published in 2022 showed that since 1979 the Arctic has warmed nearly four times faster than the global average. One key reason is a vicious circle: snow and ice reflect most sunlight, while the dark ocean they uncover as they melt absorbs most of it. The more the ice melts, the more the region heats up, and the more ice melts.
On 27 August 1883, the eruption of the Indonesian volcano Krakatoa was heard as far away as Rodrigues Island, nearly 4,800 km away. Its pressure wave was picked up by barometers worldwide and circled the globe several times. The tsunamis that followed killed more than 36,000 people.
The deepest known point in the ocean, Challenger Deep, lies roughly 10,900 m below the Pacific surface. Drop Everest in and its summit would still sit about 2 km underwater. Down there, the pressure is more than 1,000 times what you feel at sea level, roughly a tonne pressing on every square centimetre.