Shimla (historically spelt Simla) is cooler than Amritsar even though they lie on nearly the same latitude. What is the main geographical reason for this temperature difference?

Introduction / Context:
Temperature at a place is influenced by many geographical factors such as latitude, altitude, distance from the sea, and local winds. This question uses the example of two well known Indian cities, Shimla and Amritsar, that are at roughly similar latitudes but experience very different temperatures. It tests whether you can correctly identify which factor explains why Shimla remains cooler.

Given Data / Assumptions:

• Shimla and Amritsar are located at almost the same latitude in northern India.
• Shimla is a hill station in the Himalayas, while Amritsar lies in the plains of Punjab.
• We assume normal seasonal conditions without unusual weather events.

Concept / Approach:
Latitude mainly controls the amount of solar energy received, so places on the same latitude receive roughly similar incoming solar radiation. However, temperature also falls with increasing altitude. A general rule of thumb is that temperature decreases by about six and a half degrees Celsius for every thousand metres of elevation in the lower atmosphere. Shimla is situated at an altitude of more than two thousand metres above sea level, while Amritsar is close to the plains at a low elevation. Therefore, in spite of having similar latitude, Shimla is much cooler primarily because of its greater height above sea level.

Step-by-Step Solution:
Step 1: Recognise that both Shimla and Amritsar are in northern India and broadly share the same latitude zone.Step 2: Recall that the key difference between them is altitude: Shimla is a hill station at high elevation; Amritsar is in the plains at low elevation.Step 3: Apply the environmental lapse rate concept, which states that temperature generally decreases with height in the troposphere.Step 4: Because Shimla is thousands of metres higher, the air there is cooler than at Amritsar.Step 5: Therefore, identify greater height above sea level as the main reason for Shimla being cooler.

Verification / Alternative check:
If latitude were the only factor, then both cities would have similar temperatures, which is not the case. Also, the slight difference in longitude between the two has almost no effect on average temperature; it mainly affects local time. Observations from weather records consistently show that high altitude hill stations like Shimla remain cooler than low lying plains even when they share similar latitudes, confirming that altitude is the dominant reason in this comparison.

Why Other Options Are Wrong:
Shimla is farther north: In reality their latitudes are quite similar, so this is not the key factor.Shimla is farther from the equator: Because both cities have nearly the same latitude, this statement does not distinguish between them.Their longitudes differ significantly: Longitude affects time rather than temperature and cannot explain why one city is cooler than the other.

Common Pitfalls:
Some students focus too much on latitude and forget to consider altitude. Others think that small differences in distance from the equator or longitude can cause large temperature gaps, which is not true. Always remember that temperature falls noticeably with height, so highlands and hill stations are cooler than nearby lowland cities at the same latitude.

Final Answer:
Shimla is cooler than Amritsar mainly because Shimla is at a much greater height above sea level than Amritsar.