The jet aircrafts fly very easily and smoothly in the lower stratosphere. What could be the appropriate explanation? 1. There are no clouds or water vapour in the lower stratosphere. 2. There are no vertical winds in the lower stratosphere. Which of the statements given above is/ are correct in this context?

Jet aircraft fly in the lower stratosphere because it offers ideal conditions for smooth flight. Firstly, the stratosphere is almost free from clouds and associated weather phenomena because it contains very little water vapor [3]. While rare nacreous clouds can exist, the layer is generally dry and clear. Secondly, the stratosphere is characterized by temperature inversion, where temperature remains constant or rises with altitude [1]. This thermal stratification prevents convection, resulting in a lack of vertical winds and high atmospheric stability. While strong horizontal winds like jet streams exist near the tropopause, the absence of vertical air movement and convective turbulence makes the lower stratosphere much smoother than the troposphere [1]. Therefore, both the absence of clouds/water vapor and the lack of vertical winds are correct explanations for why jets prefer this layer.

Sources

1. [1] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 20: Earths Atmosphere > Stratosphere (12 to 50 km) > p. 275
2. [3] https://education.nationalgeographic.org/resource/parts-atmosphere/