Podcast
Questions and Answers
Which layer of the atmosphere is directly responsible for most weather phenomena?
Which layer of the atmosphere is directly responsible for most weather phenomena?
What happens to air when it becomes warmer?
What happens to air when it becomes warmer?
How does the Coriolis force affect air movement in the Northern Hemisphere?
How does the Coriolis force affect air movement in the Northern Hemisphere?
What is a characteristic of the Hadley Cell in the atmospheric circulation model?
What is a characteristic of the Hadley Cell in the atmospheric circulation model?
Signup and view all the answers
Which type of wind is primarily caused by the difference in temperature between the land and sea during the day?
Which type of wind is primarily caused by the difference in temperature between the land and sea during the day?
Signup and view all the answers
What is indicated by closely spaced isobars on a weather map?
What is indicated by closely spaced isobars on a weather map?
Signup and view all the answers
What occurs at the tropopause?
What occurs at the tropopause?
Signup and view all the answers
Which wind pattern occurs at night when the land cools faster than the sea?
Which wind pattern occurs at night when the land cools faster than the sea?
Signup and view all the answers
What is a primary factor for the unequal heating of the Earth's surface?
What is a primary factor for the unequal heating of the Earth's surface?
Signup and view all the answers
Which wind is characterized as a downslope wind that can be either warm or cold?
Which wind is characterized as a downslope wind that can be either warm or cold?
Signup and view all the answers
What is atmospheric stability primarily characterized by?
What is atmospheric stability primarily characterized by?
Signup and view all the answers
What is the average lapse rate of temperature decrease with altitude?
What is the average lapse rate of temperature decrease with altitude?
Signup and view all the answers
Which type of air tends to be the most stable?
Which type of air tends to be the most stable?
Signup and view all the answers
In a temperature inversion, how does temperature change with altitude?
In a temperature inversion, how does temperature change with altitude?
Signup and view all the answers
What does the dew point indicate?
What does the dew point indicate?
Signup and view all the answers
Which type of fog occurs on clear, calm, and humid nights?
Which type of fog occurs on clear, calm, and humid nights?
Signup and view all the answers
Which of the following types of clouds is classified as a low cloud?
Which of the following types of clouds is classified as a low cloud?
Signup and view all the answers
What is the primary characteristic of cumulus clouds?
What is the primary characteristic of cumulus clouds?
Signup and view all the answers
What does the term 'latent heat' refer to in the context of weather?
What does the term 'latent heat' refer to in the context of weather?
Signup and view all the answers
What results from super-cooled water droplets in the atmosphere?
What results from super-cooled water droplets in the atmosphere?
Signup and view all the answers
What happens to the air density when moisture content increases?
What happens to the air density when moisture content increases?
Signup and view all the answers
What is the primary cause of precipitation?
What is the primary cause of precipitation?
Signup and view all the answers
Which type of clouds are generally associated with severe weather conditions?
Which type of clouds are generally associated with severe weather conditions?
Signup and view all the answers
What impact can frost have on aircraft performance?
What impact can frost have on aircraft performance?
Signup and view all the answers
Study Notes
Atmospheric Structure and Composition
- Atmosphere: Mixture of gases surrounding Earth, fairly uniform in proportion up to 260,000 feet.
- Layered structure: Defined by criteria like temperature.
- Troposphere: Surface to ~36,000 feet, higher in summer and at the equator. Most weather occurs in this layer.
- Tropopause: Top of troposphere, marks location of jet streams and thunderstorms.
- Stratosphere: Extends to ~160,000 feet.
- Mesosphere and Thermosphere: Higher layers with differing compositions.
- Composition: Nitrogen (78%), Oxygen (21%), Other (1%), Water Vapor (0-4%).
Atmospheric Circulation
- Driven by Unequal Heating: Earth's rotation and differential solar radiation.
- Convection: Warmer, less dense air rises (equator), cooler, denser air sinks (poles), creating a circulation pattern.
- Three-Cell Pattern: Hadley, Ferrel, and Polar cells.
- Atmospheric pressure: Unequal heating leads to variations in air density and atmospheric pressure.
Atmospheric Pressure and Winds
- Isobars: Lines connecting points of equal pressure, used on weather maps.
- Pressure Gradient: Change in pressure over distance. Close isobars = strong gradient, resulting in stronger winds.
- Pressure Systems: High pressure (clockwise flow), Low pressure (counterclockwise flow), ridges, and troughs.
- Air Flow: From high-pressure, cool, dense air to low-pressure, warm, less dense air.
- Coriolis Force: Deflection of air due to Earth's rotation (to the right in the Northern Hemisphere, to the left in the Southern Hemisphere. Affects air flow path; deflection increases with speed.
- Friction: Slows air near Earth's surface, minimizing Coriolis effect. Pressure gradient force is still greater, driving air toward low pressure.
Local Wind Patterns
- Sea Breeze: Daytime heating of land causes rising air, cooler air from the sea moves in to replace it (10-20 knots, 1500-3000 ft AGLL).
- Land Breeze: Land cools faster than water at night, reversing the sea breeze (1000-2000 ft AGL).
- Valley Breeze: Mountain slopes heated by the sun causing warm air to ascend (5-20 knots, max several hundred feet).
- Mountain Breeze: Nighttime cooling of mountains causes cooler air to descend into valley (5-15 knots, max 25 knots).
- Katabatic Winds: Strong downslope winds, often over ice or snow-covered terrains (speeds can exceed 100 knots).
- Warm Downslope Winds: Warm air descending mountains, compression and warming of air (20-50 knots). Examples: Chinook, Föhn, Santa Ana.
Atmospheric Stability and Temperature
- Stability: Resistance to vertical motion (stable = smooth air, unstable = turbulence, clouds).
- Adiabatic Heating/Cooling: Temperature changes during air movement due to expansion/compression.
- Lapse Rate: Rate of temperature decrease with altitude, averages 2ºC per 1,000 ft. Moist air cools slower.
- Temperature Inversions: Temperature increasing with altitude, creating a lid, poor visibility, stable air.
- Frontal Inversions: Temperature inversions related to fronts.
- Radiation Inversion: Temperatures near the ground fall below those above due to cooling of surface.
Moisture and Precipitation
- Humidity: Moisture content in the air, including relative humidity (actual vs. possible).
- Dewpoint: Temperature at which air becomes saturated.
- Dew and Frost: Condensation and deposition, respectively, form on surfaces below the dewpoint.
- Clouds: Formed when air cools to saturation, diverse types categorized by altitude.
- Precipitation: Water or ice falling from the atmosphere; causes many aviation challenges.
- Types of Precipitation: Drizzle (liquid) etc...
Aviation Implications
- Many aspects of weather directly impact aircraft operations.
- Temperature, moisture, and air stability all influence turbulence and visibility, which affect safety and flight planning.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your understanding of atmospheric structure and circulation. This quiz covers the layers of the atmosphere, their characteristics, and the principles driving atmospheric circulation patterns. Challenge yourself with questions on topics such as the troposphere, stratosphere, and atmospheric pressure.
