Atmospheric Stability Flashcards

Questions and Answers

What does stability refer to in atmospheric terms?

The tendency of an air parcel, with its water vapor, to either remain in place or change vertical position by rising or falling.

What will a stable parcel of air do?

Resist displacement upward, or when disturbed, it tends to return to its starting place.

What will an unstable parcel of air do?

Continue to rise until it reaches an altitude where the surrounding air has a density and temperature similar to its own.

Which of the following rules apply to atmospheric stability? (Select all that apply)

The Environmental Lapse Rate (ELR) determines air stability. Signup and view all the answers

What is the definition of the Environmental Lapse Rate (ELR)?

The actual temperature lapse rate in the lower atmosphere at any particular time under local weather conditions. Signup and view all the answers

Match the types of stability to their descriptions:

Absolute Stability = Typically results in no uplift of air, often associated with high pressure cells. Absolute Instability = Usually results in uplift of air parcel, associated with low pressure cells. Conditional Instability = Occurs under specific conditions related to temperature. Temperature Inversion = When the air temperature increases with increasing altitude. Signup and view all the answers

What is a temperature inversion?

When the air temperature is increasing with increasing altitude in the troposphere. Signup and view all the answers

What characterizes absolute instability?

ELR > DAR; often leads to uplift of air parcel and cloud formation. Signup and view all the answers

What characterizes conditional instability?

SAR < ELR; depends on specific atmospheric conditions. Signup and view all the answers

Study Notes

Atmospheric Stability Overview

Stability refers to an air parcel's tendency to remain in place or change vertical position by rising or falling, influenced by its temperature and water vapor content.

Characteristics of Air Parcels

A stable air parcel resists upward displacement and returns to its original position when disturbed.
An unstable air parcel continues to rise until it reaches an altitude with similar density and temperature to its surroundings.

Rules of Stability

A warmer air parcel compared to its surroundings will rise, indicating unstable air.
A cooler air parcel will remain at the same level or sink, indicating stable air.
The Environmental Lapse Rate (ELR) describes the temperature profile of the atmosphere and is critical for determining air stability.

Environmental Lapse Rate (ELR)

ELR is the actual temperature lapse rate in the lower atmosphere at a given time, influenced by local weather conditions.

Types of Stability

Types include absolute stability, absolute instability, and conditional instability.

Absolute Stability

Occurs when ELR is less than the Dry Adiabatic Rate (DAR).
Results in no uplift of air and often leads to sinking air.
Typically associated with high-pressure systems, leading to clear skies with minimal cloud cover, potentially a few stratus clouds.
A significant example is temperature inversion.

Temperature Inversion

Defined by a situation where air temperature increases with altitude within the troposphere, contrary to normal behavior.

Absolute Instability

Occurs when ELR exceeds the DAR.
Usually results in uplift of air parcels, commonly linked to low-pressure systems.
Frequently occurs during warm months and clear days, often leading to cloud formation, particularly cumulus clouds, and precipitation.

Conditional Instability

Characterized by a situation where the ELR is greater than the Saturated Adiabatic Rate (SAR), indicating conditions where air can become unstable under specific humidity conditions.

Description

Test your knowledge on atmospheric stability with these flashcards. Learn about the behavior of stable and unstable air parcels and their definitions. Perfect for students studying meteorology or atmospheric sciences.