Why?

Waves

When the wind blows across the water, it changes the water's surface, first into ripples and then into waves. Once the surface becomes uneven, the wind has an ever increasing grip on it. Storms can make enormous waves, particularly if the wind, blows in the same direction for any length of time. Waves travel effortlessly along the water's surface. This is made possible by small movements of the water molecules. The wind blows over the water, changing its surface into ripples and waves. As waves grow in height, the wind pushes them along faster and higher. Waves can become unexpectedly strong and destructive.

Without waves, the world would be a different place. Waves cannot exist by themselves for they are caused by winds. Winds in turn are caused by differences in temperature on the planet, mainly between the hot tropics and the cold poles but also due to temperature fluctuations of continents relative to the sea.

Without waves, the winds would have only a very small grip on the water and would not be able to move it as much. The waves allow the wind to transfer its energy to the water's surface and to make it move. At the surface, waves promote the exchange of gases: carbon dioxide into the oceans and oxygen out. Currents and eddies mix the layers of water which would otherwise become stagnant and less conducive to life. Nutrients are thus circulated and re-used.

The large ocean currents transport warm water from the tropics to the poles and cold water the other way. They help to stabilise the planet's temperature and to minimise its extremes. For instance, because of warm ocean currents arriving from the north, the temperature of New Zealand is 3-4 degrees higher than it would be without them.

For the creatures in the sea, ocean currents allow their larvae to be dispersed and to be carried great distances. Many creatures spawn only during storms when large waves can mix their gametes effectively.

Coastal creatures living in shallow water experience the brunt of the waves directly. In order to survive there, they need to be robust and adaptable. Thus waves maintain a gradient of biodiversity all the way from the surface, down to depths of 30m or more. Without waves, there would not be as many species living in the sea.

Waves pound rocks and make them erode faster, but sea organisms covering these rocks, delay this process. Waves make beaches by transporting sand from deeper down towards the shore and by washing the sand and removing fine particles. Waves stir and suspend the sand so that currents or gravity can transport it.

What direction does a sea breeze blow?

It depends on the time of day. The ground heats up and cools more quickly than the sea. When the ground has warmed up more than the sea then air moves towards the land from the sea and heads upwards in a thermal and then downwards again out to sea. At night the opposite happens, as the ground cools the cold air flows down to the sea and again upwards in a thermal. Night sea breezes are usually less windy than in the day as the sun is not pumping energy into the system

Air in the atmosphere

Earth's atmosphere is pressing against each square inch of you with a force of 1 kilogram per square centimeter (14.7 pounds per square inch). The force on 1,000 square centimeters (a little larger than a square foot) is about a ton! Why doesn't all that pressure squash me? Remember that you have air inside your body too, that air balances out the pressure outside so you stay nice and firm.

Generally, high- and low-pressure systems form when air mass and temperature differences between the surface of the Earth and the upper atmosphere create vertical currents. In a low-pressure system, these vertical winds travel upwards and suck air away from the surface of the Earth like a giant vacuum cleaner, decreasing the air pressure above the ground or sea. This decrease in surface air pressure in turn causes atmospheric currents moving parallel to the surface of the Earth near the base of the low to spin counter clockwise (clockwise in the Southern Hemisphere). Lows function like giant slow-moving hurricanes. The lower in pressure a low-pressure system gets, the more robust and larger this spinning circulation pattern becomes Tornadoes, also known as Twisters, can be as destructive as hurricanes on a smaller scale.

Why tides are high during full moon?

When the moon is full, it is "behind" the Earth in the sense that it's in the opposite direction of the sun. Tides rise because the Earth feels gravitational tug from the sun (let's say it's on the left) and also on the other side from the full moon (let's say it's on the right). During a new moon, both the sun and the moon are to the "left" of the Earth, so both tug on the oceans and cause tides (even higher than for full moons, as both astronomical bodies are acting on the Earth's oceans). Both sides of the equator, however, still feel the tides due to Earth's centrifugal forces (rotation!) :)

Note : This is only a scribbling note. These are purely my understanding. These may or may not be the correct one. This is not to hurt anybody's feeling.