Why were winds so important to the early explorers

When Columbus sailed the ocean blue, and for centuries before and after, ocean travel depended on the wind. Mariners knew how to get where they were going and at what time of the year based on experience with the winds.

Winds were named for their usefulness to sailors, such as the trade winds that enabled commerce between people on opposite shores. Global winds blow in belts encircling the planet. Notice that the locations of these wind belts correlate (go along with) with the atmospheric circulation cells.

Air blowing at the base of the circulation cells, from high pressure to low pressure, creates global wind belts. The global wind belts are enormous and the winds are relatively steady (see Figure below).

Let’s look at the global wind belts in the Northern Hemisphere.

• In the Hadley, cell air should move north to south, but it is deflected to the right by the Coriolis effect. So the air blows from northeast to the southwest. This belt is the trade winds, so-called because at the time of sailing ships they were good for trade.
•  In the Ferrel cell air should move south to north, but the winds actually blow from the southwest. This belt is also known as the westerly winds or westerlies.
•  In the Polar cell, the winds travel from the northeast and are called the polar easterlies.

The wind belts are named for the directions from which the winds come. The westerly winds, for example, blow from west to east. These names hold for the winds in the wind belts of the Southern Hemisphere as well.

Global Winds and Precipitation

The high and low-pressure areas created by the six atmospheric circulation cells also determine in a general way the amount of precipitation a region receives. Rain is common in low-pressure regions due to rising air. Air sinking in high-pressure areas causes evaporation; these regions are usually dry. These features have a great deal of influence on climate.

Polar Front

The polar front is the junction between the Ferrel and Polar cells. At this low-pressure zone, the relatively warm, moist air of the Ferrel Cell runs into the relatively cold, dry air of the Polar cell. The weather where these two meets is extremely variable, typical of much of North America and Europe.

Jet Stream

The polar front is the junction between the Ferrel and Polar cells. At this low-pressure zone, the relatively warm, moist air of the Ferrel Cell runs into the relatively cold, dry air of the Polar cell. The weather where these two meets is extremely variable, typical of much of North America and Europe.

Conclusion:

Jet streams move seasonally just as the angle of the Sun in the sky moves north and south. The polar jet stream, known as “the jet stream,” N°moves south in the winter and north in the summer between about 30 N.° to 75°and 50