SEA LEVEL DATA FACILITY

Flightradar24.com - Live flight tracker! Ocean trench: Take a dive 11,000m down Icy cold, pitch black and with crushing pressures - the deepest part of the ocean is one of the most hostile places on the planet. Only three explorers have made the epic journey there: 11km (seven miles) down to the bottom of the Pacific Ocean's Mariana Trench. As a new wave of deep-sea exploration begins, take a look at the mysterious world that they will be plunging into. Pressure Test: Diving 100m down With the help of some polystyrene heads, science reporter Rebecca Morelle finds out what happens at the pressure experienced 100m below sea level. Pressure Test: Diving 1,000m down The BBC's Rebecca Morelle reveals what happens to a polystyrene head as it is subjected to the pressure 1,000m below the waves. Atmospheric diving suit They may look as clunky as a suit of armour but some atmospheric diving suits (ADS) can enable people to reach depths of up to 600-700m. Elephant seal - expert diver This southern elephant seal is a fantastic diver and reach depths of up to 2,000m.