The Atmosphere | PPL(A) Meteorology - EASA & UK CAA
Adiabatic processes
Section titled "Adiabatic processes"Refer to figure ppl-050-006. What does the attached diagram show?
Select the correct option.
Saturated Adiabatic Lapse Rate (SALR):
Refer to figure ppl-050-007. What does the attached diagram show?
Environmental Lapse Rate (ELR):
Adiabatic means:
Dry Adiabatic Lapse Rate (DALR):
Refer to figure ppl-050-008. What does the attached diagram show?
Air Density
Section titled "Air Density"Density is __(1)__ and __(2)__.
The base atmospheric ISA density is:
Evaluate the statements: 1. If the pressure is lower, the air is less dense. 2. Lower air pressure means a lower density altitude and better aircraft performance.
Air masses
Section titled "Air masses"Select the correct option(s):
Thermodynamic modification of an air mass:
Select the correct option(s):
Air masses can be classified on the basis of their geographical locations as:
Select the correct option.
Select the correct option(s):
Air temperature
Section titled "Air temperature"A surface temperature inversion:
Evaluate the statements: 1. All objects whether hot or cold emit radiant energy continuously 2. Hotter objects emit more energy per unit area than colder objects
Transfer of heat by the vertical movement of a mass or substance from one place to another, is called:
If unsaturated air rises far enough, its temperature will reach its dew point temperature, __(1)__ will begin to form. This altitude is known as the __(2)__.
The temperature of an object determines the __(1)__ of radiation, the __(2)__ the object, the shorter the length of the wave.
On the Fahrenheit scale, water freezes at __(1)__ and boils at __(2)__ (at sea level).
Sometimes, the temperature in the lower layers of air increases instead of decreasing with elevation. This condition, opposite to the normal vertical distribution of temperature, is known as:
What is the process of heat transfer from a warmer object to a cooler object when they come in contact with each other?
Refer to the METAR. At approximately what height is the cloud base expected? LGSR 200850Z 21007KT 9999 FEW 17/10 Q1022
__(1)__ is the rate of temperature change occurring within a rising or descending air parcel, and its value is not highly variable. __(2)__ is the rate of decrease of temperature with altitude in the stationary atmosphere at a given time and location. It is __(3)__.
The angle of incidence or the angle which the sun's rays make with the earth's surface, determines the amount of solar radiation which a particular place on the Earth will receive. The area covered by the vertical rays is always __(1)__ than the slant rays. If more area is covered, the energy gets distributed and the net energy received per unit area __(2)__.
The temperature remains almost the same in the lower part of __(1)__ up to the height of 20 km After this, the temperature __(2)__ slowly with the increase in the height The temperature __(3)__ due to the presence of ozone gas in the upper part of this layer
Incoming solar radiation is known as __(1)__. It is received in the form of __(2)__ waves which are of electromagnetic nature.
Which option best describes the inversion "valley inversion"?
Frontal or advectional type of temperature inversion:
A thermometer is calibrated by marking two fixed points. The space between these fixed points is broken up into divisions called degrees. Degrees are used to indicate temperature. There are three types of temperature scales commonly used today: __(1)__, __(2)__, __(3)__.
The temperature within the ICAO standard atmosphere __(1)__ with __(2)__ height in the troposphere.
When an air parcel that is saturated with water vapour rises, ...... than it would if it were not saturated.
The upward-moving and expanding parcel of air does work, __(1)__, it __(2)__ energy, so that its temperature __(3)__.
Evaluate the statements: 1. Under given conditions, the temperatures of 10 ml and 100 ml samples of boiling water are equal. 2. The more kinetic energy the particles of an object have, the higher is the temperature of the object.
About __(1)__ of insolation is reflected into space even before reaching the Earth's surface. The remaining __(2)__ is absorbed (14 % within the atmosphere and 51 % by the Earth's surface).
Which of the following statements is correct or incorrect? 1. The Greek word diabatos means passable (from the word diabainein to cross over). 2. In thermodynamics diabatic means transfer of heat. The 'a' at the start of the word adiabatic means without, so 'adiabatic' means 'no heat transfer'.
The Earth's surface radiates energy to the atmosphere in the form of __(1)__ waves This energy __(2)__ the atmosphere from bottom to top
Evaluate the statements: 1. The varying environmental lapse rates throughout the Earth's atmosphere are of critical importance in meteorology. 2. The dry adiabatic lapse rate for the Earth's atmosphere is constant. 3. The moist adiabatic lapse rate varies considerably because the amount of water vapour in the air is highly variable.
If the environmental lapse rate is between the moist and dry adiabatic lapse rates, then:
If the environmental lapse rate is larger than the dry adiabatic lapse rate:
Evaluate the statements: 1. Very small suspended particles in the troposphere scatter visible spectrum both to space and towards the Earth's surface. This process adds colour to the sky. 2. Absorption of solar radiation takes place if the obstructing particles happen to be water vapour, ozone molecules, carbon dioxide molecules or clouds.
On the Celsius scale and at sea level, water freezes at __(1)__ and boils at __(2)__
The Earth's surface after being heated up by the insolation (in the form of short waves), it starts to transfer energy to the atmosphere in the form of long waves. This way of heat transfer is:
At the winter solstice (22 December), the southern hemisphere receives __(1)__ sunshine as it is summer there, while at the summer solstice (21 June), the northern hemisphere receives __(2)__ sunshine as it is summer time there.
When air is hot, it tends to __(1)__, which __(2)__ its density.
Which of the following statements about the angle of the insolation (solar radiation) with the surface of the Earth is correct?
If the environmental lapse rate is less than the moist adiabatic lapse rate, then:
Evaluate the statements: 1. The oceanic winds have the capacity to take the moderating influence of the sea to coastal areas. 2. The leeward side or the interiors do not get the moderating effect of the sea, and therefore experience extremes of temperature.
As heat is added to a gas, the molecules move __(1)__. This increased motion causes a small increase in the volume, or amount of space, taken up by most materials. There are devices that use the expansion of a substance to give an indirect measure of temperature. Such devices are called __(2)__.
Evaluate the statements: 1. Maximum insolation is received over the subtropical desert, where the cloudiness is the least. 2. The heat capacity of the oceans is higher than the heat capacity of the continents.
Evaluate the statements: 1. The temperature of an object can affect some properties of the object such as the length of a solid, or the gas pressure in a closed vessel, or the electrical resistance. 2. Two objects are in thermodynamic equilibrium when they have the same temperature.
A subsidence inversion:
A turbulence inversion:
Evaluate the statements: 1. Two objects are in thermodynamic equilibrium when they have the same temperature. 2. If two objects of different temperatures are brought into contact with one another, they will establish a thermodynamic equilibrium.
The dry adiabatic lapse rate for the Earth's atmosphere equals __(1)__ per kilometer, and this value is not highly variable. The environmental lapse rate (ELR) value is highly variable, but an average value is __(2)__ per kilometre for an idealised ISA.
The dry adiabatic lapse rate for the Earth's atmosphere is __(1)__ per km. Thus, the temperature of an air parcel that ascends or descends 5 km would fall or rise __(2)__, respectively.
20 °C is:
0 °F is:
In a __(1)__ gas, the molecules __(2)__ than in a __(3)__ gas.
The transfer of heat through horizontal movement of air (wind) is called:
Temperature inversion takes place only under certain specific conditions such as:
Altimetry
Section titled "Altimetry"Absolute altitude:
The indicated altitude is 2000 ft and the outside air temperature (OAT) is -15 °C. Calculate the true altitude:
True altitude:
At high ambient temperatures, the atmosphere retains a higher water vapour content. The air density changes because water vapour weighs __(1)__ than dry air. Therefore, as the water content of the air increases, the air becomes __(2)__, __(3)__ density altitude and __(4)__ performance.
Density altitude:
If the value indicated by an altimeter is based upon standard 1013.25 hPa reference, then the indicated value is:
Pressure altitude:
With ...... set on the subscale, your altimeter will read zero on the reference point of the airport.
The density of the air __(1)__ with increasing altitude. A "high" density altitude means that air density is reduced, __(2)__.
You are at an airport where pressure altitude is 5500 ft. SAT is +35 °C. What is density altitude?
Evaluate the statements: 1. Altimeters are affected by the venturi effect of winds blowing across the terrain. 2. The winds create a localized "low pressure area".
With ...... set in the subscale, your altimeter will show flight level.
Indicated altitude:
The __(1)__ the air, the less dense it is. When the temperature rises above the standard temperature for a particular place, the density of the air in that location is __(2)__, and the density altitude __(3)__.
When temperature is __(1)__ than ISA an aircraft will be __(2)__ than the altimeter reading.
If the value indicated by an altimeter is the elevation of the aircraft above runway threshold, then the indicated value is:
If the altimeter reference is set to QNH:
If the value indicated by an altimeter is the elevation of the aircraft above mean sea level (AMSL), then the indicated value is:
Anticyclone
Section titled "Anticyclone"Select the correct option(s):
Which of the following options on anticyclones (high pressure) is correct?
When isobars enclose an area of high pressure this is called a:
When isobars turn a sharp corner around a High, they form what is called a:
Cold anticyclones:
Select the correct option(s):
Atmospheric Pressure
Section titled "Atmospheric Pressure"What is an elongated area of relatively low pressure called?
The atmosphere is always trying to correct imbalances. As a result, the convergence of air around a surface low is approximately offset by __(1)__. The divergence of air around a surface high is approximately offset by __(2)__.
Determine at what altitude the air pressure is half than at sea level.
An elongated area of relatively high pressure is known as:
While air swirls inward and converges into the centre of surface low pressure, an "upper-level disturbance" causes divergence aloft that allows air columns to shed weight.
When isobars make a sharp bend around a Low, this bend area is called a:
Evaluate the statements: 1. Winds always blow directly along the isobars. 2. The closer the isobars, the stronger the winds.
As elevation __(1)__, atmospheric pressure __(2)__.
What is the area is called when isobars make a sharp bend around a High?:
"As air swirls outward away from the center of surface high pressure, upper-level convergence allows air columns to gain mass"
Isobars can make shapes and patterns. When isobars enclose an area of high pressure, it is called:
What is the reduction of the station pressure to mean sea level, if the station is 64m AMSL, and the barometer at the station shows 1024 hPa?
On mean sea level (MSL) weather charts, isobars join together places with equal air:
The __(1)__ the isobars, the __(2)__ the winds.
The isobars make shapes and patterns. When they enclose an area of low pressure, what is it called?
In the northern hemisphere, if you look into the wind, the lower pressure:
Change of state of water
Section titled "Change of state of water"Condensation may occur by:
Whenever a water molecule leaves a surface and diffuses into a surrounding gas, it is said to have:
The __(1)__ the dew point rises, the __(2)__ the amount of moisture the air can hold.
Select the correct option(s):
When thermal energy is added to a substance, its temperature increases, which can change its state from liquid to gas. This is called:
In the atmospheric water / water vapor system an increase in temperature leads to ...... evaporation and an increase in pressure leads to ...... evaporation.
When thermal energy is added to a substance, its temperature increases, which can change its state from or solid to gas. This is called:
When energy is removed, decreasing the substance's temperature and turning it from liquid to solid is called:
Select the correct option(s):
When energy is removed, decreasing the substance's temperature and turning from gas to liquid is called:
Select the correct option(s):
Select the correct option(s):
Select the correct option(s):
Select the correct option(s):
When thermal energy is added to a substance, its temperature increases, which can change its state from solid to liquid. This is called:
Cloud formation and description
Section titled "Cloud formation and description"Mid-level clouds:
The signs of an inversion are the following:
What forms when warm, moist air passes over a cool surface.
What is formed when water vapour is added to air that is much colder than the water vapour's source? (Commonly occuring when very cold air drifts across relatively warm water)
Refer to figure ppl-050-009. What is cloud number 5?
Refer to figure ppl-050-011. Which of the following figures shows Altocumulus lenticularis?
Refer to figure ppl-050-009. What is cloud number 9?
When warm moist air is forced up the slope of a mountain, it cools and the water vapor condenses into:
By definition in fog visibility is less than:
Refer to figure ppl-050-016. What clouds are depicted in the figure?
High-level clouds:
Refer to figure ppl-050-009. What is cloud number 8?
Main type(s) of low clouds include:
Refer to figure ppl-050-009. What is cloud number 3?
Refer to figure ppl-050-009. What is cloud number 4?
Refer to figure ppl-050-013. What type of clouds are present in the attached figure?
Refer to figure ppl-050-009. What is cloud number 6?
Refer to figure ppl-050-009. What is cloud number 1?
When warm rain falls through cooler air, it can make the surrounding air saturated with moisture and form a thick layer of fog. This usually happens with warm fronts. This type of fog is:
Refer to figure ppl-050-009. What is cloud number 10?
Refer to figure ppl-050-009. What is cloud number 7?
Refer to figure ppl-050-012. What type of clouds are present in the attached figure?
Select the correct option.
A temperature ...... is a layer in the atmosphere in which air temperature increases with height.
Refer to figure ppl-050-014. What clouds are depicted in the attached figure?
If an air parcel is lifted where will condensation occur?
Refer to figure ppl-050-009. What is cloud number 2?
What forms in the evening when the heat absorbed by the Earth's surface during the day is radiated into the air at night?
Refer to figure ppl-050-015. What type of clouds are present in the attached figure?
Refer to figure ppl-050-010. What clouds are depicted in the figure?
Refer to figure ppl-050-011. Which of the following figures shows a towering cumulus cloud?
Composition, extent and vertical division
Section titled "Composition, extent and vertical division"The troposphere contains __(1)__ of the total mass of the planetary atmosphere, and __(2)__ of the total mass of water vapour and aerosols.
What is the lowest layer of the atmosphere?
Where does most weather phenomena occur?
The atmosphere of Earth is composed of:
From the planetary surface of the Earth, the average height of the troposphere is __(1)__ in the tropics; and __(2)__ in the high latitudes of the polar regions.
Definition and measurement of wind
Section titled "Definition and measurement of wind"The wind given by the Tower is based on:
According to ICAO, a windsock is mounted at a mast height so that it is clearly visible, and the taper of the fabric windsock from the throat to the trailing end must be designed to cause the windsock to fully extend when exposed to a wind of:
Fronts
Section titled "Fronts"Choose the correct option:
What type of front is formed when a cold front overtakes warm front and warm air is completely displaced from the ground surface?
The warm front precipitation in thr case of stable warm air is:
From the following options, select the correct and most complete answer:
Select the correct option.
If a cold front is approaching:
If warm front is approaching:
The front is the sloping boundary which separates:
After the passage of the cold front:
If a warm front is passing over:
If a cold front is passing over:
After the passage of a warm front:
The sequence of clouds form, in case of warm front of stable warm air:
A cold front is associated with:
What front is that gently sloping frontal surface along which warm and light air rises slowly over cold and dense air?
An occluded front:
Select the correct option.
Select the correct option(s):
What is the sloping frontal surface along which cold air invades the warm air territory and being denser remains at the ground but forcibly uplifts the warm and light air.
After the cold front:
In case of a cold front:
General global circulation
Section titled "General global circulation"What is the primary cause of the Earth's general global circulation (wind)?
What is the name of the wind pattern that blows from east to west between 30° north and south?
Which wind pattern is found near the equator and is characterized by calm conditions with little wind?
Which of the following winds predominantly affect weather systems in the mid-latitudes (30 to 60 degrees)?
Humidity
Section titled "Humidity"Which of the following quantities remains unchanged if unsaturated air is lifted until it reaches the condensation level?
What is the "mixing ratio"?
ICAO standard atmosphere
Section titled "ICAO standard atmosphere"Evaluate the statements: 1. The higher the altitude, the less dense the air. 2. When operating on airports at higher elevations, special attention is required when calculating aircraft performance data.
What is the ISA value of temperature at mean sea level?
What is the ISA value of pressure at mean sea level?
Local winds
Section titled "Local winds"A land breeze:
Katabatic winds:
A Sea breeze:
Anabatic winds:
Mountain waves (standing waves, lee waves)
Section titled "Mountain waves (standing waves, lee waves)"What conditions are needed for the formation mountain waves?
Lee waves are standing waves in the air that form ...... of a hill or mountain range as winds pass over them.
Mountain waves:
What are other words for Mountain Waves?:
Evaluate the statements: 1. When airflow approaches a mountain at an almost right angle, it rises while traversing the mountain. If it reaches an inversion layer, the airflow is pushed downward. 2. Given the stability of the air, it endeavours to return to its original elevation, sparking an oscillation. As air ascends within the wave pattern, it cools and condenses into a cloud that settles atop each wave crest. This cloud displays a distinct lens-like shape.
Non-frontal depressions
Section titled "Non-frontal depressions"If an air mass is lifted by a mountain range, may cause a __(1)__ on the leeward slope causing the formation of a localised __(2)__.
Select the correct option(s):
When isobars turn a sharp corner around a Low they form a:
Tropical Maritime (Warm air) migrating to the north from the tropics meets Polar Maritime (cold dense air) migrating south from the Polar region.
Primary cause of wind
Section titled "Primary cause of wind"Air flows from regions of __(1)__ atmospheric pressure. However, when the wind speed increases, the Coriolis effect, caused by __(2)__, influences the wind's direction, causing it to align with the isobars.
Wind can be considered as __(1)__ flow of atmospheric air. The predominant factor behind wind formation is __(2)__.
In the Northern Hemisphere, if a person stands with his back to the wind, the atmospheric pressure is:
Due to the __(1)___ rotation speed at the Equator compared to the poles, if you throw a ball in a straight line toward the North in the Northern Hemisphere, it will seem to land to the __(2)___ of your position because the ground beneath it is moving slower.
To find surface wind direction, you need to take the wind which is parallel to the isobars and:
What happens to the Coriolis force when friction slows the wind speed down?
When winds are subject to __(1)__, they cause air to flow outward from the region. This kind of flow is typically associated with __(2)__.
Turbulence
Section titled "Turbulence"Wind shear exists:
Light turbulence:
Refer to figure ppl-050-017. Based on the attached figure, what is the meaning of the sign?
Severe turbulence:
Refer to figure ppl-050-005. Based on the attached figure, what is the meaning of the sign?
Which of the following statements refer to "moderate turbulence"?
The __(1)__ the wind, the more irregular the terrain and the __(2)__ the air, the stronger the turbulence.
Select the correct option(s) about heating of the earth's surface and thermal turbulence:
Types and development of precipitation
Section titled "Types and development of precipitation"What kind of cloud can produce rain or snow?
What kind of cloud can give drizzle?
From the following options, select the correct phases of the development of precipitation.