Ocean

Water possesses the unusual property of being able to absorb a large amount of heat energy before its temperature changes. It follows that water must lose a large amount of heat energy before it cools noticeably. The net result of this phenomenon is that water, more than air or earth, tends to remain at the temperature at which it is already. Water is not given to sudden, wild extremes of temperature. Therefore water has a strong moderating effect on climates. Where there is water, there are more moderate temperatures. A "maritime" (meaning "ocean-like") climate means a moist climate that rarely experiences temperature extremes.

Nearly all coasts experience this maritime effect, but it is especially apparent along coasts where there are large-scale oceanic currents. The moderating effects of the Gulf Stream are a good example. Caribbean sunshine warms the waters of the Gulf Stream in the tropics. This warm water then flows up the east coast of the United States and finally crosses the Atlantic to the coast of Western Europe. This warm current is why England's climate is so much warmer than areas at about the same latitude in North America. However, when the Gulf Stream is diverted southward, Western Europe experiences extreme cold-the last such event, during the fourteenth through nineteenth century, is known as the "Little Ice Age."