Why, on a sunny summer's day is the land much hotter than the sea?
Why are the average precipitation amounts different at the same latitude?
Climatic conditions associated with continental areas are characterized by marked temperature contrasts between night and day and from season to season. The sun's "rays" strike the Earth's surface providing energy in the form of heat. Some of this energy re-radiates back into the atmosphere and warms the air. Some is absorbed by a very thin layer of the Earth's crust. This thin layer warms up very quickly. It also cools down just as rapidly. However, in the sea, solar radiation penetrates much deeper and further. The heat energy spreads through a greater volume. The result is that the sea may warm up slower than the land but it retains its heat for longer. The earth in contrast, gains and looses heat more quickly than the sea.
Our planet is a water planet. Like atmospheric air, the waters of the oceans are mixed and circulated. One of the key roles of water on Earth is to transfer heat from the tropics to higher latitudes. This is done both by the movement of ocean waters (currents) and by the movement of water in the atmosphere. Warm water from the tropics flows towards the poles, and cold water from the polar regions flows towards the equator.
Winds blowing over warm ocean currents are warmed. They also pick up moisture from the water surface. When these moist winds reach the land, they bring rain. Marine climates are characterized by small annual and diurnal temperature variation and by copious rainfall on the windward side of coastal highlands and mountainous islands. Coastal regions tends to have more stable temperatures throughout the year.
Not all coastal environments have the same precipitation patterns. For example, the Atlantic and Pacific coasts of the North American continent have different current patterns and prevailing winds that result in different kinds of marine climates.
However, both these marine climates have moderate temperature extremes and have considerable moisture in the air.