Between which latitudes does the Doldrums low pressure belt, characterised by calm winds and rising air, mainly lie?

Introduction / Context:
The Doldrums is a traditional maritime term for the equatorial zone of low pressure and calm or variable winds, associated with rising warm air and frequent thunderstorms. It plays an important role in global atmospheric circulation and is a favourite topic in physical geography. This question asks you to recall the approximate latitudinal extent of the Doldrums low pressure belt, testing your understanding of global wind belts and pressure zones near the equator.

Given Data / Assumptions:
- Four latitude ranges are provided as options. - The Doldrums refers to the equatorial low pressure belt. - We must identify the latitude band that best represents this belt. - The ranges are given in degrees north and south of the equator.

Concept / Approach:
The equatorial low pressure belt, or Inter Tropical Convergence Zone, is centred around the equator where trade winds from both hemispheres converge and air rises due to intense heating. This zone is typically described as extending about 5 degrees north and south of the equator, though it can shift seasonally. The other options, such as 25 deg to 35 deg or 35 deg to 60 deg, correspond more to subtropical high pressure or mid latitude westerly zones, not to the equatorial calm belt. Therefore, the correct latitude range for the Doldrums is approximately 5 deg N to 5 deg S.

Step-by-Step Solution:
Step 1: Recall that the Doldrums is another name for the equatorial low pressure belt. Step 2: Recognise that this belt lies very close to the equator, not in mid or subtropical latitudes. Step 3: Among the options, only 5 deg N to 5 deg S straddles the equator symmetrically and remains close to it. Step 4: The ranges 25 deg N to 35 deg S and 35 deg N to 45 deg S are too far from the equator and are associated with other pressure belts and wind systems. Step 5: Therefore, the Doldrums pressure belt is best represented by the latitude range 5 deg N to 5 deg S.

Verification / Alternative check:
You can verify by recalling standard diagrams of global circulation cells (Hadley cells) and the Inter Tropical Convergence Zone. In these diagrams, the equatorial low pressure zone is drawn as a narrow band on either side of the equator, typically marked around 0 to 5 degrees north and south. Meanwhile, the subtropical high pressure belts appear around 25 to 35 degrees latitude, clearly separate from the Doldrums. This visual memory confirms the correct answer.

Why Other Options Are Wrong:
35 deg N to 60 deg S is wrong because it covers a very wide range across subtropical and mid latitude regions, not the narrow equatorial calm belt.

25 deg N to 35 deg S is wrong because it mainly includes part of the subtropical high pressure zone and not the equatorial Doldrums.

35 deg N to 45 deg S is also wrong as it lies completely outside the equatorial region, again covering only mid latitude areas.

Common Pitfalls:
Some students misremember the latitude ranges associated with different global circulation features and may confuse the Doldrums with the Horse Latitudes, which lie in the subtropical high pressure belt around 30 degrees latitude. Others misinterpret the diagrammatic representation and think the Doldrums cover a wider range than they actually do. To avoid such mistakes, memorise the standard association: Doldrums around 0 to 5 degrees, Horse Latitudes around 30 degrees, and westerlies in mid latitudes beyond that.

Final Answer:
The Doldrums low pressure belt mainly lies between 5 deg N to 5 deg S latitudes.