The tsunami is a result of the volcanic and earthquake activity on the plate boundaries in the ocean. It forms when there's a big disturbance in the oceanic crust, and from all the force and stress released, the water is becoming very turbulent.
At first, the waters of the ocean/sea are dragged towards the crack where the volcanic or earthquake activity appeared, and after that, under enormous pressure the water is pushed out again. The water now has very big speed and very big power. As it nears the shore it creates huge waves, and once these waves reach the land they destroy most things in front of them.
The standard atmospheric pressure that is measured formthe sea levels to the surface to the high altitudes of the earth is the 1013.25 millibar or is 17 pounds per inches as the air over the higher altitudes is more sensitive and it's measured in pascal.
<u>And are a function of the plant's mass and the radius of the surface and the amount of the distribution of the gases and the vertical distribution of the air. And hence is calculated by the values that are reduced to the mean sea levels. </u>
