Oceans cover about 70% of the Earth's surface.The oceans affect many things on the Earth,especially the weather and temperature.The oceans are all connected to one another.There were four recognized oceans:the Pacific,Atlantic,Indian,and Arctic.
The oceans and seas contain about 5 x 10 16 tons of salts.The salt content of ocean water is different.The least salty seas are in the North and South poles,because of the melting ice and a lot of rain.
There are many waves on the oceans,the winds cause waves.If the winds are stronger,the waves will be larger.A tsunami is a series of huge waves,it caused by an underwater earthquake,or a small comet hit the ocean.
Tide rises and falls of large area of water.Tides are caused by the gravitational interaction between the Earth and the Moon.
The water cycle starts form oceans.The water from ocean to air to ground to ocean.
There are many animals live in the oceans,too.海洋覆盖了大约70%的地球表面.海洋影响许多地球上的事物,特别是天气和温度.海洋是一个接一个组成的.有四个公认的海洋:太平洋、大西洋、印度洋、和北冰洋.海洋和海水里含盐大约5058吨.海水的含盐量是不同的.最淡的海水在北极和南极,因为融化的冰和大量的降雨稀释了盐度.海洋中有很多浪头,是风引起的.如果风强,海浪将会更大.海啸是一系列的巨浪,它引起了由海底地震或是一颗很小的彗星撞击了海洋.涨潮或者落潮.潮汐是地球和月球相互作用引起的.
水的循环开始形成海洋.海水到大气到地面再到海洋.
海洋中也有许多动物