The total ocean area on the earth is about 360 million square kilometers, accounting for 7 1% of the earth's surface area, with an average water depth of about 3795 meters. The ocean contains more than1350 million cubic kilometers of water, accounting for about 97% of the total water of the earth, and only 2% is available for human consumption.
The ocean is one of the main factors that determine the development of the earth's climate. The ocean itself is the largest heat storage body on the earth's surface. Ocean current is the largest heat energy conveyor belt on the earth's surface. The gas exchange between ocean and air has great influence on climate change and development.
Marine disasters mainly refer to sudden natural disasters such as storm surges, huge waves, sea ice, sea fog, strong winds, earthquakes and tsunamis. The main causes of marine disasters are strong atmospheric disturbances, such as tropical cyclones and temperate cyclones.