is there a law that governs it?
Yes,"Freedom of the seas", the United Nations Convention on the Law of the Sea (UNCLOS), International Maritime Organization.
Sea
"Freedom of the seas" is a principle in international law dating from the seventeenth century. It stresses freedom to navigate the oceans and disapproves of war fought in international waters. Today, this concept is enshrined in the United Nations Convention on the Law of the Sea (UNCLOS), the third version of which came into force in 1994. Article 87(1) states: "The high seas are open to all states, whether coastal or land-locked." Article 87(1) (a) to (f) gives a non-exhaustive list of freedoms including navigation, overflight, the laying of submarine cables, building artificial islands, fishing and scientific research. The safety of shipping is regulated by the International Maritime Organization. Its objectives include developing and maintaining a regulatory framework for shipping, maritime safety, environmental concerns, legal matters, technical co-operation and maritime security.

UNCLOS defines various areas of water. "Internal waters" are on the landward side of a baseline and 
which of the following is not generally a factor in wave generation in the open ocean UNANSWERABLE what is the definition of 'sea'? The sea, the world ocean, or simply the ocean is the connected body of salty water that covers over 70% of Earth's surface. what is meant by 'seawater'? It is water in the sea a characteristic of seawater is that it is salty. how do waves form? Wind blowing over the surface of a body of water forms waves that are perpendicular to the direction of the wind. and tsunamis? It is an unusual form of wave caused by an infrequent powerful event such as an underwater earthquake or landslide, a meteorite impact, a volcanic eruption or a collapse of land into the sea. what affects currents? The sea causes friction at the interface between air and sea. what are 'tides'? They are the regular rise and fall in water level experienced by seas and oceans in response to the gravitational influences of the Moon and the Sun, and the effects of the Earth's rotation. what is meant by 'ocean basin'? The oceanic crust is composed of relatively dense basalt and is some five to ten kilometres (three to six miles) thick. name some marine habitats? Coral reefs, cold water reefs harbour a wide array of species including corals. which algae is found here? Sargassum, kelp, meadows to name a few. and plants? Plant growth is higher like planktons.
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Sea [SEP] Law
"Freedom of the seas" is a principle in international law dating from the seventeenth century. It stresses freedom to navigate the oceans and disapproves of war fought in international waters. Today, this concept is enshrined in the United Nations Convention on the Law of the Sea (UNCLOS), the third version of which came into force in 1994. Article 87(1) states: "The high seas are open to all states, whether coastal or land-locked." Article 87(1) (a) to (f) gives a non-exhaustive list of freedoms including navigation, overflight, the laying of submarine cables, building artificial islands, fishing and scientific research. The safety of shipping is regulated by the International Maritime Organization.