During the sailing navigation navigators could easily rely on the constancy of the winds on both sides of the equator. They searched the area where the trade winds blow, and avoided areas dominated by calm. These extensive windless zone "horse latitudes" - located at the trade winds around the Northern and southern hemispheres.
Called these areas to calm the horse latitudes" Spanish sailors transporting horses from the Old world in the Spanish colonies on open Columbus American continent, where they were not. When the ships of the Spaniards fell in locations with no wind, the sails were loose, the movement stopped, the feed stocks were not enough, many horses killed, and threw them overboard.
But over the continents, there are areas where the winds blow regularly. The most famous of these winds, monsoons. The monsoon is very strong rainy stormy winds that blow inland from the ocean and the climate in the tropics. They carry air masses in tropical countries, on the coasts of the Indian ocean.
To understand how form monsoons, we must remember that for many months the climate in monsoon areas are very dry (over land atmospheric pressure is higher than over the sea). The wind, as you know, blowing from the high pressure area in the region is low.
In summer, the Asian continent is heated, and the atmospheric pressure above it falls. Over the Indian ocean on the contrary, it increased. Here and there the wind blowing in summer, from ocean to land. And the wind it is very wet, as he flew over the expanse of the warm sea. Therefore, the rains are long and heavy. The monsoon coastal countries owe their fertility. Sometimes the monsoons bring devastating floods.
In winter these winds, on the contrary, blow into the ocean with cold spaces of the continent, where the atmospheric pressure is higher than over warm ocean waters. These monsoons cause drought. Rain may not be a whole year until the next monsoon period.
In areas of monsoon lives about a quarter of the entire population of the planet. In the Northern hemisphere monsoons happen in June, in Australia in December.
The wettest place on Earth in the midst of the monsoon season - Cherrapunji in India. There in this period every day you get almost 1 meter of precipitation!