Atmosphere Contents

1. Structure And Composition

The lowest of the layers in the atmosphere is called the troposphere

The troposphere stretches from the surface up to a height of 10 km to 15 km. It is where most of our weather occurs. It contains most of the mass of the atmospheric gases and, importantly for meteorology, nearly all of the water vapour and aerosols. In the troposphere the temperature decreases with height at 6.5°C/km. This is known as the 'atmospheric lapse rate'. Troposphere literally means turning sphere and this refers to the constant overturning of the air by convective motions. The convective motions occur because the temperature decreases with height allowing warmer, more buoyant, air to rise and cooler, less buoyant, air to sink.

What is the troposphere?