Water vapour acts like a blanket that holds heat close to the ground. In deserts, the very dry air and often cloudless skies let the day's heat escape to space as soon as the Sun sets. Day-to-night temperature swings can exceed 20 to 30 °C, and on some winter nights it freezes.
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.