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The environmental lapse rate in an actual atmosphere ? [ Revision flight ]

Question 133-1 : Varies with time has a fixed value of 1°c/100m has a fixed value of 0 65°c/100m has a fixed value of 2°c/1000 ft

exemple 233 Varies with time. — Varies with time.

The dry adiabatic lapse rate has a value of ?

Question 133-2 : 1°c/100 m 2°c/1000 ft 0 65°c/100 m 0 5°c/100 m

exemple 237 1°c/100 m. — Admin .the dry adiabatic lapse rate has a constant fixed value of 1°c/100 m 3°c/1000 ft 1°c/100 m.

The dry adiabatic lapse rate ?

Question 133-3 : Has a constant fixed value is greater in summer than in winter is greater during the night than during the day has a variable value

Admin .the dry adiabatic lapse rate has a constant fixed value of 1°c/100 m 3°c/1000 ft

An air mass is called stable when ?

Question 133-4 : The vertical motion of rising air tends to become weaker and disappears the temperature in a given air mass decreases rapidly with height the pressure in a given area is constant the environmental lapse rate is high with little vertical motion of air currents

exemple 245 The vertical motion of rising air tends to become weaker and disappears — The vertical motion of rising air tends to become weaker and disappears

Advection is ?

Question 133-5 : Horizontal motion of air vertical motion of air the same as subsidence the same as convection

Admin .advection is horizontal motion of air .subsidence is vertically downwards motion of air .convection is vertically upwards motion of air

Subsidence is ?

Question 133-6 : Vertically downwards motion of air horizontal motion of air vertically upwards motion of air the same as convection

exemple 253 Vertically downwards motion of air. — Admin .advection is horizontal motion of air .subsidence is vertically downwards motion of air .convection is vertically upwards motion of air Vertically downwards motion of air.

Rising air cools because ?

Question 133-7 : It expands surrounding air is cooler at higher levels it becomes more moist it contracts

exemple 257 It expands. — It expands.

A layer can be ?

Question 133-8 : Stable for unsaturated air and unstable for saturated air stable for saturated air and unstable for unsaturated air unstable for unsaturated air and neutral for saturated air unstable for unsaturated air and conditionally unstable

exemple 261 Stable for unsaturated air and unstable for saturated air. — Admin .if the environmental lapse rate elr is more than 3°c/1000 ft dry adiabatic lapse rate the environment is unstable .if the environmental lapse rate elr is less than 1 8°c/1000 ft saturated adiabatic lapse rate the environment is stable .but .if the environmental lapse rate elr is more than 1 8°c/1000 ft but less than 3°c/1000 ft we have conditional stability . stable if air is dry unsaturated .or. unstable if air is saturated Stable for unsaturated air and unstable for saturated air.

In a layer of air the decrease in temperature per 100 metres increase in height ?

Question 133-9 : Absolutely unstable absolutely stable conditionally unstable conditionally stable

exemple 265 Absolutely unstable. — Admin .more than 1°c/100 m = more than 3°c/1000 ft .if the environmental lapse rate elr is more than 3°c/1000 ft dry adiabatic lapse rate the environment is unstable .if the environmental lapse rate elr is less than 1 8°c/1000 ft saturated adiabatic lapse rate the environment is stable .if the environmental lapse rate elr is more than 1 8°c/1000 ft but less than 3°c/1000 ft we have conditional stability . stable if air is dry unsaturated .or. unstable if air is saturated Absolutely unstable.

Which statement is true for a conditionally unstable layer ?

Question 133-10 : The environmental lapse rate is less than 1°c/100 m the environmental lapse rate is less than 0 65°c/100 m the layer is unstable for unsaturated air the wet adiabatic lapse rate is 0 65°c/100 m

exemple 269 The environmental lapse rate is less than 1°c/100 m. — Admin .more than 1°c/100 m = more than 3°c/1000 ft .if the environmental lapse rate elr is more than 3°c/1000 ft dry adiabatic lapse rate the environment is unstable .if the environmental lapse rate elr is less than 1 8°c/1000 ft saturated adiabatic lapse rate the environment is stable .if the environmental lapse rate elr is more than 1 8°c/1000 ft but less than 3°c/1000 ft we have conditional stability . stable if air is dry unsaturated .or. unstable if air is saturated The environmental lapse rate is less than 1°c/100 m.

The stability in a layer is increasing if ?

Question 133-11 : Warm air is advected in the upper part and cold air in the lower part warm air is advected in the lower part and cold air in the upper part warm and moist air is advected in the lower part cold and dry air is advected in the upper part

exemple 273 Warm air is advected in the upper part and cold air in the lower part. — Admin .it is similar to an inversion .if a parcel of air is forced to rise it will be colder than the air it is rising into so the moment the trigger stops lifting it it will sink back to the level it started from because it is more dense the layer is stable Warm air is advected in the upper part and cold air in the lower part.

Which of the following statements concerning the lifting of a parcel of air is ?

Question 133-12 : Unsaturated parcels cool more rapidly than saturated parcels unsaturated parcels cool less rapidly than saturated parcels unsaturated parcels cool at a rate of 0 65°c per 100 m saturated parcels always cool at a rate of 0 65°c per 100 m

exemple 277 Unsaturated parcels cool more rapidly than saturated parcels. — Admin .there is less moisture in an unsaturated parcels to retain heat Unsaturated parcels cool more rapidly than saturated parcels.

When in the upper part of a layer warm air is advected the ?

Question 133-13 : Stability increases in the layer stability decreases in the layer wind will back with increasing height in the northern hemisphere wind speed will always decrease with increasing height in the northern hemisphere

exemple 281 Stability increases in the layer. — Admin .it is similar to an inversion .if a parcel of air is forced to rise it will be colder than the air it is rising into so the moment the trigger stops lifting it it will sink back to the level it started from because it is more dense the stability increases in the layer Stability increases in the layer.

The dew point temperature ?

Question 133-14 : Can be equal to the air temperature is always lower than the air temperature is always higher than the air temperature can not be equal to the air temperature

exemple 285 Can be equal to the air temperature. — Can be equal to the air temperature.

Relative humidity depends on ?

Question 133-15 : Moisture content and temperature of the air moisture content and pressure of the air moisture content of the air only temperature of the air only

exemple 289 Moisture content and temperature of the air — Moisture content and temperature of the air

When water evaporates into unsaturated air ?

Question 133-16 : Heat is absorbed heat is released relative humidity is not changed relative humidity is decreased

exemple 293 Heat is absorbed. — Admin .a known phenomena when water evaporates into unsaturated air is that the air is cooled the water transitioning from a liquid state to a gaseous state is transitioning from a lower energy state to a higher energy state the energy required for this transition to take place is provided to the water in the form of heat that is taken out of the surrounding air this latent heat of vaporization leaving the air causes a temperature of the air to be reduced Heat is absorbed.

A moist but unsaturated parcel of air becomes saturated by ?

Question 133-17 : Lifting the parcel to a higher level lowering the parcel to a lower level moving the parcel to an area with lower pressure and equal temperature moving the parcel to an area with higher pressure and equal temperature

exemple 297 Lifting the parcel to a higher level. — Admin .air can hold a certain amount of water depending on it's temperature warmer air can hold more water vapour than colder air .thus by cooling the air it can hold less water vapour and the relative humidity increases how does air cool usually by increasing in height .so to get an unsaturated parcel of air with say 40% of relative humidity to 100% of relative humidity fully saturated a cloud then you must cool the parcel by lifting it to a higher level Lifting the parcel to a higher level.

A sample of moist but unsaturated air may become saturated by ?

Question 133-18 : Expanding it adiabatically raising the temperature lowering the pressure keeping temperature constant compressing it adiabatically

exemple 301 Expanding it adiabatically. — Fabricet .don't get why an unsaturated air mass could become saturated by expanding it adiabatically by compressing it the relative humidity will increase until reaching the 100% of humidity making the air mass saturated . .if you compress it it will heat up and if you expand it will cool .during an adiabatic process heat is neither added nor lost air can hold a certain amount of water depending on it's temperature warmer air can hold more water vapour than colder air .thus by cooling the air it can hold less water vapour and the relative humidity increases how does air cool usually by increasing in height .so to get an unsaturated parcel of air with say 40% of relative humidity to 100% of relative humidity fully saturated a cloud then you must cool the parcel by lifting it to a higher level when it expands adiabatically it cools so relative humidity must increase Expanding it adiabatically.

The maximum amount of water vapour that the air can contain depends on the ?

Question 133-19 : Air temperature relative humidity stability of the air dewpoint

exemple 305 Air temperature. — Admin .the most commonly used measure of humidity is relative humidity relative humidity can be simply defined as the amount of water in the air relative to the saturation amount the air can hold at a given temperature multiplied by 100 air with a relative humidity of 50% contains a half of the water vapor it could hold at a particular temperature . 501. concept of relative humidity .we can say that the amount of water vapour which air can hold largely depends on air temperature Air temperature.

Convective clouds are formed ?

Question 133-20 : In unstable atmosphere in stable atmosphere in summer during the day only in mid latitudes only

exemple 309 In unstable atmosphere. — In unstable atmosphere.

The most effective way to dissipate cloud is by ?

Question 133-21 : Subsidence convection a decrease in temperature a decrease in pressure

exemple 313 Subsidence. — Subsidence.

Areas of sinking air are generally cloudless because as air sinks it ?

Question 133-22 : Is heated by compression reaches warmer layers is heated by expansion loses water vapour

exemple 317 Is heated by compression. — Admin .as the air sinks to lower levels the pressure increases which compresses the air increasing density and temperature .as the air temperature increases its capacity to hold water vapour increases and relative humidity decreases Is heated by compression.

The main factor which contributes to the formation of very low clouds ahead of ?

Question 133-23 : Saturation of the cold air by rain falling into it and evaporating saturation of the warm air by rain falling into it and evaporating reduction of outgoing radiation due to clouds warm air moving over a cold surface

exemple 321 Saturation of the cold air by rain falling into it and evaporating. — Admin .clouds form in the front rain falls from them out of the warm sector into the cold sector . 559.latent heat is absorbed when going from liquid to gas vapour at low levels you will have stratus and nimbostratus clouds Saturation of the cold air by rain falling into it and evaporating.

In an unstable layer there are cumuliform clouds the vertical extent of these ?

Question 133-24 : Thickness of the unstable layer wind direction air pressure at the surface pressure at different levels

exemple 325 Thickness of the unstable layer — Thickness of the unstable layer

Which of the following phenomena are formed when a moist stable layer of air is ?

Question 133-25 : Stratified clouds inversions showers and thunderstorms areas of severe turbulence

exemple 329 Stratified clouds. — Admin .lifting moist stable layer of air produces stratus Stratified clouds.

The height of the lifting condensation level is determined by ?

Question 133-26 : Temperature and dewpoint at the surface temperature at surface and air pressure wind and dewpoint at the surface wet adiabatic lapse rate and dewpoint at the surface

exemple 333 Temperature and dewpoint at the surface. — Admin . 560.the height of a cloud base that results from lifting of near surface air can be estimated based on the surface values of temperature and dew point since the height at which a cloud will form is roughly the height at which the temperature and dew point would become equal due to expansion of the air as it rises to regions of lower pressure Temperature and dewpoint at the surface.

During an adiabatic process heat is ?

Question 133-27 : Neither added nor lost added lost added but the result is an overall loss

exemple 337 Neither added nor lost. — Neither added nor lost.

The decrease in temperature per 100 metres in an unsaturated rising parcel of ?

Question 133-28 : 1°c 2°c 0 65°c 0 5°c

exemple 341 1°c. — Admin .1°c/100 m or 3°c/1000 ft this is the dry adiabatic lapse rate 1°c.

The decrease in temperature per 100 metres in a saturated rising parcel of air ?

Question 133-29 : 0 6°c 1°c 1 5°c 0 35°c

exemple 345 0.6°c. — Admin .dry lapse rate = 3ºc/1000 ft or 1ºc/100 m.saturated lapse rate = 1ºc/1000 ft or 0 6ºc/100 m 0.6°c.

In unstable air ground visibility is most likely to be restricted by ?

Question 133-30 : Showers of rain or snow haze drizzle low stratus

exemple 349 Showers of rain or snow. — Showers of rain or snow.

A vertical temperature profile indicates the possibility of severe icing when ?

Question 133-31 : Intersects the 0°c isotherm twice coincides with a dry adiabatic lapse rate indicates temperatures below 40°c indicates temperatures above 3°c

exemple 353 Intersects the 0°c isotherm twice. — Admin .to intersect the 0ºc isotherm twice there must be warm air above cold air this occurs at a warm front and is where rain ice will be encountered Intersects the 0°c isotherm twice.

The rate of cooling of ascending saturated air is less than the rate of cooling ?

Question 133-32 : Heat is released during the condensation process moist air is heavier than dry air water vapour doesn't cool as rapidly as dry air water vapour absorbs the incoming heat from the sun

exemple 357 Heat is released during the condensation process. — Heat is released during the condensation process.

If the surface temperature is 15°c then the temperature at 10000 ft in a ?

Question 133-33 : 15°c 0°c 5°c 5°c

exemple 361 -15°c. — Admin . ascending unsaturated air means dry adiabatic lapse rate and we know that the environmental lapse rate elr is more than 3°c/1000ft for dry adiabatic lapse rate .15°c 3° x 10 = 15°c -15°c.

An inversion is ?

Question 133-34 : An increase of temperature with height an increase of pressure with height a decrease of pressure with height a decrease of temperature with height

exemple 365 An increase of temperature with height — An increase of temperature with height

In still air the temperature decreases at an average of 1 2°c per 100 m ?

Question 133-35 : Dry adiabatic lapse rate saturated adiabatic lapse rate environmental lapse rate normal lapse rate

exemple 369 Dry adiabatic lapse rate. — Admin .if the environmental lapse rate elr is more than 3°c/1000 ft dry adiabatic lapse rate the environment is unstable .if the environmental lapse rate elr is less than 1 8°c/1000 ft saturated adiabatic lapse rate the environment is stable .if the environmental lapse rate elr is more than 1 8°c/1000 ft but less than 3°c/1000 ft we have conditional stability . stable if air is dry .or. unstable if air is saturated .1 2°c per 100m is 3 6°c per 1000 ft .the environmental lapse rate elr is more than 3°c/1000 ft this temperature change is called 'dry adiabatic lapse rate' Dry adiabatic lapse rate.

From which of the following pieces of information can the stability of the ?

Question 133-36 : Environmental lapse rate dry adiabatic lapse rate surface temperature pressure at the surface

exemple 373 Environmental lapse rate. — Admin .if the environmental lapse rate elr is more than 3°c/1000ft dry adiabatic lapse rate the environment is unstable .if the environmental lapse rate elr is less than 1 8°c/1000ft saturated adiabatic lapse rate the environment is stable .if the environmental lapse rate elr is more than 1 8°c/1000ft but less than 3°c/1000ft we have conditional stability . stable if air is dry .or. unstable if air is saturated Environmental lapse rate.

A layer is absolutely unstable if the temperature decrease with height is ?

Question 133-37 : More than 1°c per 100m between 1°c per 100m and 0 65°c per 100m 0 65°c per 100m less than 0 65°c per 100m

exemple 377 More than 1°c per 100m. — Admin .if the environmental lapse rate elr is more than 3°c/1000 ft dry adiabatic lapse rate the environment is unstable .if the environmental lapse rate elr is less than 1 8°c/1000 ft saturated adiabatic lapse rate the environment is stable .if the environmental lapse rate elr is more than 1 8°c/1000 ft but less than 3°c/1000 ft we have conditional . stability if air is dry .or. unstability if air is saturated .the question states absolutely unstable it is more than 3°c/1000 ft .3°c/1000 ft = 1°c per 328 ft = 1°c for 100 m More than 1°c per 100m.

A layer in which the temperature remains constant with height is ?

Question 133-38 : Absolutely stable unstable neutral conditionally unstable

exemple 381 Absolutely stable. — Admin .a layer in which the temperature remains constant or increases with height is absolutely stable .for example the layer just above the tropopause is absolutely stable from 12 km to 25 km the temperature does not vary with height it is an isothermal layer where we have absolute stability Absolutely stable.

A layer in which the temperature increases with height is ?

Question 133-39 : Absolutely stable absolutely unstable conditionally unstable neutral

exemple 385 Absolutely stable. — Admin .a layer in which the temperature remains constant or increases with height is absolutely stable .for example the layer just above the tropopause is absolutely stable from 12 km to 25 km the temperature does not vary with height it is an isothermal layer where we have absolute stability Absolutely stable.

A layer in which the temperature decreases with 1°c per 100 m increasing ?

Question 133-40 : Neutral for dry air absolutely stable absolutely unstable conditionally unstable

exemple 389 Neutral for dry air. — Admin .lapse rate is 1°c for 100 m 1° per 328 ft so 3°/1000 ft we have four possibilities .if the environmental lapse rate elr is more than 3°c/1000 ft dry adiabatic lapse rate the environment is unstable .if the environmental lapse rate elr is less than 1 8°c/1000 ft saturated adiabatic lapse rate the environment is stable .if the environmental lapse rate elr is more than 1 8°c/1000 ft but less than 3°c/1000 ft we have conditional . stability if air is dry .or. unstability if air is saturated .the question states 1°c per 100m it is not more or not less than 3°c/1000 ft it will be neutral for dry air Neutral for dry air.

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