Explanation:

The adiabatic lapse rate (ALR) refers to the rate at which the temperature of a parcel of air changes as it rises or sinks in the atmosphere without exchanging heat with its surroundings. It is influenced by the compression or expansion of the air parcel.

The environmental lapse rate (ELR) refers to the actual rate at which the temperature of the surrounding atmosphere changes with altitude. It is influenced by various factors such as solar radiation, convection, and advection.

When the Adiabatic Lapse Rate (ALR) is less than the Environmental Lapse Rate (ELR), it means that the temperature of the surrounding atmosphere is decreasing at a faster rate with altitude compared to the temperature change of the rising or sinking air parcel.

Implications:

This condition has several implications for the atmosphere and weather conditions:

1. Super-Adiabatic Lapse Rate: When the ALR is less than the ELR, the prevailing environmental lapse rate is called a super-adiabatic lapse rate. This implies that the air parcel is cooler than its surroundings as it rises or warmer than its surroundings as it sinks. This condition is associated with unstable atmospheric conditions.

2. Instability: The super-adiabatic lapse rate indicates that the air parcel will continue to rise if it is already ascending, or continue to sink if it is already descending, without being influenced by its surrounding environment. This promotes vertical motion and can lead to the development of clouds, thunderstorms, and other forms of severe weather.

3. Convection: The super-adiabatic lapse rate is favorable for the development of convection. As the air parcel rises, it cools at a slower rate compared to its surroundings, leading to buoyancy and the formation of updrafts. These updrafts can fuel the growth of cumulus clouds and thunderstorms.

4. Vertical Mixing: The super-adiabatic lapse rate promotes vertical mixing of air, allowing for the exchange of heat, moisture, and pollutants between different layers of the atmosphere. This can have implications for air quality, as pollutants can be transported vertically and horizontally.

In summary, when the Adiabatic Lapse Rate (ALR) is less than the Environmental Lapse Rate (ELR), the prevailing environmental lapse rate is called a super-adiabatic lapse rate. This condition is associated with unstable atmospheric conditions, convection, and the potential for the development of severe weather.