Question

Why the name 'doldrums' used for equatorial pressure belt?

Answer 1

The equator is the hottest part of the globe and therefore it is the belt of low pressure. Though the main position of this belt is between $5^0$ N - $5^0$ S latitude, but this belt of low pressure extends more to the North than to the South of the Equator. The equatorial trough of low pressure is the zone of conversition of trade winds blowing equator ward from the sub-tropical belt of high pressure in Northern and Southern hemisphere. within this belt the winds are light and variable with frequent clams. That is why this belt is called as "Doldrums".