Q. Consider the following statements:

1. Jet streams are a narrow belt of high altitude westerly winds in the troposphere.
2. The subtropical westerly jet streams are located approximately over 27°-30° north latitude.
3. In summer, the subtropical westerly jet streams move south of the Himalayas with the apparent movement of the sun.

Which of the above is / are correct?
Answer: Only 1 and 2
Notes: Jet streams are a narrow belt of high altitude (above 12,000 m.) westerly winds in the troposphere. Their speed varies from about 110 km./h in summer to about 184 km/h in winter. A number of separate jet streams have been identified. The most constant are the mid-latitude and the sub-tropical jet streams. These jet streams are located approximately over 27°-30° north latitude, therefore, they are known as subtropical westerly jet streams. Over India, these jet streams blow south of the Himalayas, all through the year except in summer. The western cyclonic disturbances experienced in the north and north-western parts of the country are brought in by this westerly flow. In summer, the subtropical westerly jet streams move north of the Himalayas with the apparent movement of the sun. An easterly jet stream, called the sub-tropical easterly jet stream blows over peninsular India, approximately over 14°N during the summer months.

This question is part of UPSC Daily 20 MCQ Series Course on GKToday Android app.