Ch. 18 (Group 1)
What is the atmosphere
Complex mixture of molecules and atoms 78% nitrogen 21% oxygen
How are relative humidity and humidity different?
Humidity is the amount of water vapor in the air. Relative humidity is the method used to tell you the amount of water vapor that can still enter an air mass before it becomes saturated.
What is weather?
Weather is the state of the atmosphere in a specific area and time. Weather is what makes it feel hot or cold, or rainy or windy.
Radiation, high inversion, advection, and evaporation are types of...
Fog
How is fog an obstruction to the pilot visibility?
It blocks the view of the runway
This is second only to tornados for destruction, characterized by 100-200 mph winds. Develops from the warm waters off the Atlantic Ocean, in the Carribean, or Gulf of Mexico.
Hurricane
What is space
A place that extends infinitely in all directions ( no boundary between atmosphere and space)
What are the 4 ways in which heat is transferred
conduction, convection, advection, radiation
What are air masses and fronts?
An air mass is a large body of air with relatively uniform temperature and humidity.
Fronts are boundaries between air masses with different properties, such as temperature and humidity.
Give an example of how terrain affects weather
Mountain ranges can cause strong winds or as air mass goes over the mountains it loses moisture and causes snow, or other weather conditions.
What are the three stages of a thunderstorm in order?
1. Cumulous stage, 2, Mature stage, 3, Dissipating stage
What is the Saffir-Simpson Scale used for?
To determine the strength or intensity of a hurricane based on its wind speed.
What is particulate matter
Sorce of food for both soil organisms and aquatic organisms
The rate at which the Earth's surface is heated by solar radiation is called
Insolation
What is a warm front?
A warm front forms when a warm air mass overtakes a cold air mass. This results in gradual weather changes, bringing extended periods of precipitation and cloudy skies. On a weather map, a warm front is represented by a red line with semicircles pointing in the direction of movement.
How do terrain and wind impact aviation?
Terrain can limit visibility, high altitudes restrict aircraft lift. Winds over 50 miles per hour result in extreme turbulence and structural damage to an aircraft.
Violent, swirling winds rapidly rising at the center describe a...
Tornado
Name 2 hazards of severe weather to aviation.
Hail causes dents to an aircraft which is 7 times more expensive to repair than a car.
Thunderstorms cause turbulence and lightening, hazardous to aircraft.
The process by which temperature changes liquid molecules into a gas state
Evaporation
Why is heat balance important?
It makes sure the Earth's surface isn't too hot or too cold
What is a cold front
Cold fronts occur when a cold air mass advances and displaces a warm air mass. This creates rapidly changing weather conditions, often leading to thunderstorms and heavy rain. The symbol for a cold front on a weather map is a blue line with triangles pointing in the direction of movement.
This is dangerous to aircrafts during take-off and landing because of very abrupt changes in air speed. Can cause aircraft to crash. What is it?
Wind shear.
The intensity of tornadoes is measured by this
The Fujita-Pearson scale.
This is the first stage of a hurricane
Tropical depression
Name the 4 distinct atmospheric regions or layers characterized by temperature distribution, physio-chemical processes, molecular composition and kinetic (force-motion)
1. Troposphere
2. Stratosphere
3. Mesosphere
4. Thermosphere
In which direction is the wind shifted when it moves away from the equator?
It is shifted east
what is an occluded front?
an occluded front is a type of weather front formed during cyclogenesis. The classical and usual view of an occluded front is that it starts when a cold front overtakes a warm front near a cyclone, such that the warm air is separated (occluded) from the cyclone center at the surface. The point where the warm front becomes the occluded front is the triple point; a new area of low-pressure that develops at this point is called a triple-point low.
Night time radiation that cools air and extends 100 ft above the surface where the air starts to warm.
Temperature Inversion
What does CAVU stand for and what does it mean?
Ceiling and visibility unlimited and there are no hazardous weather conditions.
An aircraft could stop running if water vapor turns to ice within or on which part of the airplane?
Carburetor
This atmospheric region is only slightly more than 5 miles and is the region in which most people live. It extends from the earth's surface to 10 miles above the earth at the equator and 5 miles in height in the polar regions.
Troposphere
What is the term for an extended area of high pressure called?
An elongated area of high pressure is a RIDGE.
What is a stationary front?
A stationary front is an unmoving one, at least near Earth’s surface. Neither abutting air mass has the power to shove through the other. Such a front may form when upper-level winds that had previously propelled a front along shift and flow parallel to it, or where air masses equally matched stall one another’s movements. Even though the surficial front may be basically stable, air may be significantly moving about higher up in the atmosphere.
In aviation, what does CAT stand for and what is it?
CAT-Clear Air Turbulance
CAT is the turbulent movement of air masses without any visual clues.
What does IFR stand for and when is it used?
Instrument Flight Rules. Used when pilots need need to take off or land using instruments only due to bad weather.
When thunderstorms are present, this may form within a cumulous cloud BEFORE precipitation falls to the ground.
Hail
In this atmospheric region, temperature rises with an increase in altitude. It begins at 10 miles above the earth and extends upward 30 miles.
Stratosphere
How does external energy or thermal energy affect wind?
It affects the movement of wind.
What is a fractus cloud?
. Fractus cloud are smaller seperated clouds they are usually darker and ragged clouds.
Identify causes of CAT.
This is caused by obstructions (e.g. mountains), vertical air currents (wind causes drag on aircraft), wind sheer.
What is AGL?
Above Ground Level and tells the altitude from the ground.
An area of low pressure in which the northeast and southeast tradewinds come together, creating a vortex and some form of unsettled weather (thunderstorms or strong wind gusts up to 70mph) at all times.
Equatorial Trough
This region is at the top of the troposphere and divides the troposphere and stratosphere.
Tropopause
What is the term for when land heats up the air and it rises, so that cooler air over the sea rushes in?
Sea Breeze
What is a lenticular cloud?
Lenticular clouds are clouds that appear in circular lense shapes.
A downdraft of air during Thunderstorms is called a...
Microburst
What is the difference between Glaze and Rime icing?
Glaze icing is formed through super cooled rain droplets. Rime icing is formed through supercooled clouds.
Identify the hazards of Arctic weather to aviation.
Extreme cold and ice buildup affect aircraft performance due to strong winds, limited daylight, snow and ice and may damage the structure of the aircraft.
This region shows a marked increase in temperature (50F degrees) then the temperature decreases at 50 miles altitude and drops to -130F degrees.
Mesosphere
How does turbulence form around mountains?
What weather is associated with a nimbostratus cloud?
These large dark grey clouds are usually associated with rain or snow.
Classify the 4 types of CAT
1. light-seatbelts needed, 2. moderate-unsecured objects move around, 3. severe-aircraft is difficult to control, people objects tossed about, 4. extreme-aircraft is out of control, structural damage to aircraft
When snow covered surface removes visibility for pilots and shadowing obstructs view. This is called...
Whiteout
Identify 2 beneficial effects of severe weather.
1. Replenish water supply--precipitation
2. Thunderstorms improve air quality by clearing out pollutants
3.Hurricanes redistribute heat in the oceans
This region extends from 50 miles outward to 300 miles where temperature increases to 1380-2280F degrees. At this point we are in space.
Thermosphere
What are some characteristics of jet streams?
Strong vertical and lateral wind shears, fast cold winds, moves east to west, may reach 150-300 mph
What are the 3 general types of clouds that all other types of clouds come from? Describe each type.
1.Cumulous (piled up)-
2. Stratus (layered)-
3. Cirrus (high, thin appearance)-. D
All other types of clouds come from these three types.
Name the type of man-made turbulence caused by large aircrafts in flight which creates a vortex that may be hazardous to small aircrafts
Wake turbulence
What are the levels of the Fujita Pearson Scale and what is each level characterized by?
F0-light-- wind speeds 40-72mph
F1 Moderate (72-112mph-roof damage
F2 considerable (113-157mph) weak buildings destroyed
F3 Severe-157-206mph strong buildings gone
F4-F5 devestating and unbelievable, catostrophic
Explain the 5 categories of the Saffir-Simpson Scale.
1. (minimal) little damage (74-95 mph winds)
2. (moderate) some damage (96-110 mph winds)
3. (extensive) damage (111-129 mph winds)
4. (extreme) devestating damage (130-156mph)
5. (catastrophic) damage (157+ mph winds)