Define wind. how is it measured? how is its direction determined?
distinguish among primary, secondary, and tertiary general classifications of global atmospheric circulation.

Answer and Explanation:

The wind is a that sort of energy which flows on the surface of the Earth in the form of a current form from place to place.

In order to measure the wind, we use an instrument- anemometer which determines the wind speed and also helps in finding the direction on the of the wind on Earth.

The wind direction is determined by the arrow pointer on the anemometer which indicates the direction of the moving wind.

Primary: As a result of the high heat of the sun, the primary wind flowson the equator of the Earth within the range of 30 - 40 north and south and results in  high-pressure regions.

Secondary: These wind flows in between warmer winds on the equator to the cold polar winds and and ranges in between 60 to 70 north and south.

Tertiary: The wind that flows in the polar regions which extends in between the range of 60 to 70 north and south.

Global atmospheric circulation: The wind circulation all over the world by utilizing the heat difference and it is given by categorization  into three parts- primary, secondary and tertiary.