In the tropics the sun's rays fall on the earth's surface is almost vertical. The heated air is directed upward, and the surface is formed from an area of low atmospheric pressure, where there is no wind. There flowing cooler air masses, creating sometimes only a weak changeable winds. These movements of air masses and determine the weather in the tropics. There, in the valley, dominated by the greenhouse climate is hot and humid. As the noon sun is almost at the Zenith, the heat reaches 30° and above. At night, the air is very little cooled, because there is a high humidity. Early in the morning to breathe a little easier, but soon the sky formed a powerful Cumulus clouds in the evening often brings rain, sometimes lasted all night.
North and South of this belt, in the "horse latitudes", the cooled air descends to the surface, and there arise the field with a constant high pressure (anticyclone). The descending air masses in the form of a large spiral spin in the Northern hemisphere, clockwise, and in the South against it. In these latitudes often set a clear windless weather, the day is warm, nights are cool. Other areas of anticyclones occur at the poles.
System atmospheric pressure on Earth.
For each field of high or low pressure characterized by a certain type of weather.
For Central Europe these cyclones and anticyclones are forming. The anticyclone, born on the Azores Islands (an archipelago in the Central Atlantic), means that Europe is waiting for clear weather; cyclone over Iceland (island in the North Atlantic ocean) promises the weather; extensive cyclone over Central Asia threatens rainy then, as in the formation of a high pressure area wait for Europe's harsh winters.