Atmospheric Stability

Atmospheric Stability

Atmospheric stability refers to the state of equilibrium of the atmosphere.

ELR (Environmental Lapse Rate)

ELR is the rate at which the temperature changes with altitude.

Definition of ELR

ELR is the temperature change per kilometer of increasing altitude in the ambient atmosphere.

Variable Nature of ELR

ELR changes with time, weather, and location.

Role in Weather Prediction

ELR helps determine weather conditions like the likelihood of rain or snow.

DALR (Dry Adiabatic Lapse Rate)

DALR applies to unsaturated air parcels, i.e., air with less than 100% relative humidity.

Definition of DALR

DALR is the rate of temperature decrease with height for a parcel of dry or unsaturated air that is lifted adiabatically.

DALR Value

The standard DALR is 9.8°C per kilometer (5.5°F per 1000 feet).

Importance in Weather Forecasting

Understanding DALR allows for more accurate weather predictions.

SALR (Saturated Adiabatic Lapse Rate)

SALR refers to the rate at which the temperature of a parcel of air decreases as it ascends in the atmosphere while being saturated with water vapor.

Definition of SALR

SALR is the rate at which the temperature of saturated air decreases as the air rises.

SALR Value

It varies but is typically less than the DALR. It averages around 6°C per kilometer.

Role in Predicting Precipitation

An understanding of SALR helps predict moisture-related events like fog, rain, or snow.