Test Meteorology 1. The international standard atmosphere assumes a lapse rate of:

Geografía Meteorology

TEST DE METEO

1. The international standard atmosphere assumes a lapse rate of:

. a) 2ºC/1000 ft

. b) 1,5ºC/ 1000 ft

. c) 3ºC/1000 ft

. d) 1,98ºC/1000 ft

2. The tropopause is:

. a) The line where the temperature no longer decreases with increase of height.

. b) The layer between the tropopause and the stratosphere.

. c) The layer beyond which only CI cloud occurs.

. d) The line indicating clear air turbulence.

3. One of the most important characteristics of the atmosphere is:

. a) Density is constant above 10000 ft.

. b) The air is a poor conductor of heat.

. c) Temperature lapse rate is very frequently above 3ºC per 1000 ft.

. d) The air is a good conductor of heat.

4. Most of the vapour in the atmosphere is contained in the:

. a) tropopause

. b) stratosphere

. c) troposphere

. d) stratopause

5. The captain of an aircraft needs to know the height of the tropopause because:

. a) it normally represents the limit of weather

. b) density starts to increase

. c) there are no longer jet streams and CAT

. d) it indicates the height of the thermal wind

6. The main Ozone layer is to be found in the:

. a) termosphere

. b) troposphere

. c) mesosphere

. d) stratosphere

7. The level in the atmosphere where the air temperature ceases to fall with increase in height is known as:

. a) The troposphere.

. b) The stratopause.

. c) The stratosphere.

. d) The tropopause.

8. Which statement is correct when considering the lower layers of the atmosphere:

. a) the majority of the weather is contained in the stratosphere and its upper boundary is the tropopause

. b) the majority of the weather is contained in the troposphere and its upper boundary is the tropopause

. c) the majority of the weather is contained in the tropopause and its upper boundary is the troposphere

. d) the majority of the weather is contained in the troposphere and its upper boundary is the stratosphere

9. The atmosphere is a mixture of gases of the following proportions:

. a) oxygen 21%nitrogen 78%other gases 1%

. b) oxygen 21%hydrogen 78%other gases 1%

. c) nitrogen 78%argon 21%oxygen 1%

. d) nitrogen 78%oxygen 21%hydrogen 1%

10. In the ISA the temperature is isothermal:

. a) Up to 36090 ft/11 kms.

. b) From 36090 ft/11kms to 65617 ft/20 kms.

. c) From 36090 ft/11kms to 104987 ft/32 kms.

. d) From 36090 ft/11kms to 45090 ft/13.75 kms.

11. The international (ICAO) Standard Atmosphere assumes that the sea level atmospheric pressure is:

. a) 1013,25 mbs and decreases with an increase in height.

. b) 1013,25 mbs and increases with an increase in height.

. c) 1013,25 mbs and falls to about half this value at 30000 ft.

. d) 1013,25 mbs and decreases with an increase in height up to the tropopause. Above the tropopause it remains constant.

12. At sea level the ISA density is stated to be:

. a) 1225 grammes per cubic metre

. b) 1252 grammes per cubic metre

. c) 1013,2 mb (hPa)

. d) 29,6 inches of mercury

13. Which of the following statements is most correct when describing ISA:

. a) the MSL pressure is 1013,25 mbs and the temperature is +15ºC

. b) the MSL pressure is 1013,25 mbs and the temperature is +15ºC with a lapse rate of 1,98ºC/1000 ft

. c) the MSL pressure is 1013,25 mbs and the temperature is +15ºC with a lapse rate of 1,98ºC/1000 ft up to 36090 ft above which there is frequently an inversion

. d) the MSL pressure is 1013,25 mbs and the temperature is +15ºC with a lapse rate of 1,98ºC/1000 ft up to 36090 ft

14. The following is true for the International Standard Atmosphere:

. a) at mean sea level the following conditions prevail: Temperature +15ºC, pressure 1013,25 hpa, density 1125 gm/m3

. b) within the troposphere the temperature decreases by 6,5ºC per km

. c) the tropopause is at a height of 36090 AGL

. d) the temperature at the tropopause is 226,5 ºK

15. Pressure with increase of height and in the ISA pressure will be at 10000 ft and at 30000 ft.

. a) Increase800 mb400 mb

. b) Decrease700 mb300 mb

. c) Increase200 mb800 mb

. d) Decrease500 mb200 mb

1. The measurement of surface temperature is made:

. a) At ground level.

. b) At approximately 10 metres above ground level.

. c) At approximately 4 feet above ground level.

. d) At approximately 4 metres above ground level.

2. Cloud cover will reduce diurnal variation of temperature because:

. a) Incoming solar radiation is partially reflected back to space and outgoing terrestrial radiation is reflected back to earth.

. b) Incoming solar radiation is re-radiated back to space and atmospheric heating by convection will stop at the level of the cloud

. layer.

. c) The cloud stops the sun rays getting through to the earth and also reduces outgoing conduction.

. d) Incoming solar radiation is partially reflected back to space and outgoing terrestrial radiation is mostly re-radiated from the cloud layer back to the surface.

3. Most accurate temperatures above the ground level are obtained by:

. a) Tephigram.

. b) Aircraft reports.

. c) Temperature probes.

. d) Radio sonde.

4. The diurnal variation of temperature is:

. a) Greater over sea than overland.

. b) Less over desert areas than over temperate grassland.

. c) Reduced anywhere by the presence of cloud.

. d) Increased anywhere as wind speed increases.

5. Over continents and oceans, the relative temperature conditions are:

. a) Warmer in winter over land, colder in summer over sea.

. b) Colder in winter over land, warmer in winter over sea.

. c) Cold in winter over land and sea.

. d) Warmer in summer over land and sea.

6. The process of change of state from a liquid mass to a gas mass is:

. a) Condensation in which latent heat is released.

. b) Evaporation in which latent heat is released.

. c) Condensation in which latent heat is absorbed.

. d) Evaporation in which latent heat is absorbed by the mass.

7. Air is classified as dry or saturated according to its relative humidity. If the relative humidity were 95% the air would be classified as:

. a) Conditionally saturated.

. b) Not saturated.

. c) Saturated.

. d) Dry.

8. On a wet bulb thermometer in an unsaturated atmosphere there will be a reduction of temperature below that of the dry bulb thermometer because:

. a) Heat is absorbed during the process of condensation.

. b) Heat is released during the process of condensation.

. c) Heat is absorbed by the thermometer during the process of evaporation.

. d) Heat is released from the thermometer during the process of evaporation.

9. Relative humidity is:

. a) Air temperature over wet bulb temperature * 100.

. b) Air temperature over dew point temperature * 100.

. c) The actual mixing ratio of water vapour in a sample of air over the maximum mixing ratio of water vapour that this sample can contain* 100.

. d) The maximum amount of water vapour that a sample of air can contain over the actual amount of water vapour the sample does contain * 100.

10. Absolute humidity is:

. a) The number of water droplets in a given quantity of air.

. b) The mass of water vapour that a volume of air holds.

. c) The maximum amount of water vapour that a given quantity of air can hold.

. d) The maximum number of water droplets that a given quantity of air can hold.

11. Wet bulb temperature would normally be lower than the dry bulb temperature because

. a) condensation causes a release of latent heat.

. b) evaporation causes cooling of the bulb.

. c) latent heat is absorbed by the bulb thermometer.

. d) of condensation on the muslin wick of the bulb.

12. The wet bulb temperature:

. a) Is measured using a hydrometer.

. b) Is the minimum temperature to which a thermometer bulb can be cooled by the evaporation of water.

. c) Measures the dew point of air.

. d) Is the minimum temperature reached by the surface of the earth as measured by a thermometer placed 1.2 metres above the ground.

13. Which one of the following statements relating to atmospheric humidity is correct:

. a) If the air temperature falls then the absolute humidity must increase.

. b) The absolute humidity is the mass of water vapour contained in unit volume of air.

. c) The diurnal variation of dewpoint temperature is greatest when skies are clear at night.

. d) The dewpoint temperature is the temperature indicated by the wet bulb thermometer.

14. When condensation takes place, the higher temperature, the the amount of latent heat :

. a) lesser released

. b) grater absorbed

. c) greater released

. d) lesser absorbed

15. When water vapour changes to ice:

. a) Latent heat is absorbed.

. b) Specific heat is released.

. c) Latent heat is released.

. d) Specific heat is absorbed.

16. Throughout the 24hrs of a day the Relative Humidity can be expected to:

. a) Increase during the day and decrease at night.

. b) Stay reasonably constant throughout the 24 hours.

. c) Reduce during the day and increase at night.

. d) Only change with a change of airmass.

17. During a night with a clear sky, surface temperature will RH will and dewpoint will :

. a) Fall, rise rise.

. b) Rise, rise, fall.

. c) Fall, rise, remain the same.

. d) Fall, fall, remain the same.

18. A change of state directly from a solid to a vapour or vice versa is:

. a) Insolation.

. b) Condensation.

. c) Evaporation.

. d) Sublimation.

19. The instrument used for measuring the humidity of air is a:

. a) Hydrometer.

. b) Hygrometer.

. c) Wet bulb thermometer.

. d) Hygroscope.

20. The process of change of state from a gas to a liquid is:

. a) Evaporation in which latent heat is absorbed.

. b) Evaporation in which latent heat is released.

. c) Condensation in which latent heat is absorbed.

. d) Condensation in which latent heat is released.

1. A trough of low pressure is generally associated with:

. a) Convergence causing increased cloud and precipitation.

. b) Divergence causing increased cloud and precipitation.

. c) Subsidence causing increased cloud and precipitation.

. d) Subsidence causing decreased cloud and precipitation.

2. A ridge of high pressure is generally associated with:

. a) Convergence causing increased cloud and precipitation.

. b) Divergence causing increased cloud and precipitation.

. c) Divergence causing cloud to break up and more precipitation.

. d) Divergence and subsidence causing clear skies and good weather.

3. An area of indeterminate pressure between two lows and two highs is called:

. a) A trough.

. b) A ridge.

. c) A col.

. d) A saddle.

4. An aircraft is flying at 3000 feet indicated with the altimeter sub scale set to 1020 mb towards a mountain range with an elevation of 1600 feet. If during the flight the QNH in the area falls to 989 mb and the altimeter sub scale is not reset, the exp

. a) 1400 ft.

. b) 470 ft.

. c) 930 ft.

. d) 563 ft.

5. The altimeter subscale is set to 1030 mbs and the altimeter reads 4500’. QNH is 996 mb. What is the altitude of the aircraft? (Assume 1mb =27’):

. a) 3480’.

. b) 3990’.

. c) 5418’.

. d) 3582’.

6. If in the southern hemisphere an aircraft in flight at 2000 ft is experiencing starboard drift, the aircraft is flying towards:

. a) An area of high pressure.

. b) An area of low pressure.

. c) A warm front.

. d) A depression.

1. When moist air passes over a surface which is than the dew point of the air, fog can form. This occurs over .

. a) cool warmer radiation the sea

. b) warm cooler radiation the land only

. c) cool warmer frontal land

. d) warm cooler advection land and sea

2. Radiation fog is most likely at an inland airfield in the UK with a relative humidity of 80% in the _ with and a wind of .

. a) Autumn clear skies 2-8 knots

. b) Spring 6/8 ST & SC 2-10 knots

. c) Winter clear skies 15/20 knots

. d) Summer clear skies no wind

3. Fog may be defined as:

. a) A reduction of visibility to less than 1000 metres due to the presence of water vapour in the atmosphere.

. b) A reduction of visibility to less than 1000 metres due to the presence of water droplets in suspension in the atmosphere.

. c) A reduction of visibility to less than 1500 metres due to the presence of water droplets in suspension in the atmosphere.

. d) A reduction of visibility to less than 1000 ft due to the presence of water vapour in the atmosphere.

4. Several types of pressure distribution may be associated with radiation fog but all have one feature in common which is:

. a) Closely spaced isobars.

. b) A tight pressure gradient.

. c) A slack pressure gradient.

. d) A rapidly falling pressure.

5. Advection fog:

. a) Only occurs at night and early morning.

. b) Is most likely with Polar Maritime air.

. c) Will only clear by insolation.

. d) Can sometimes last for 24 hours in winter.

1- What does the expression "Broken (BKN)" mean?

. a) Nil significant cloud cover

. b) 3-5 Eights of the sky is cloud covered

. c) 3-4 Eights of the sky is cloud covered

. d) 5-7 Eights of the sky is cloud covered

2- In which of the following 19:00 UTC METAR reports, is the probability of fog formation, in the coming night, the highest?

. a) 041900Z 21010KT 7000 BKN020 16/14 Q1019 NOSIG=

. b) 041900Z 00000KT 9999 FEW030 SCT100 17/14 Q1017 NOSIG=

. c) 041900Z 00000KT 6000 NSC 13/12 Q1019 BECMG 3000 BR=

. d) 041900Z 00000KT 9999 FEW030 SCT100 17/14 Q1017 NOSIG=

3- What does the abbreviation "NOSIG" mean?

. a) No weather related problems

. b) No report received

. c) No significant changes

. d) Not signed by the meteorologist

4- You receive the following METAR:LSGG 120730Z 00000KT 0300 R05/0700N FZFG VV001 M02/M02 Q1014 NOSIG =

5- What does this mean in a weather chart

. a) severe icing between levels 280 and 360

. b) light turbulence from ground to a level between levels 280 and 360

. c) moderate turbulence between levels 280 and 360

. d) Mountain waves between levels 280 and 360

6- Refer to the following TAF extract:TAF LELC 050500Z 0506/0606 VRB04KT 9999 FEW040 TX24/0512Z TN14/0506Z BECMG 0508/0511 11010KT BECMG 0518/0521 VRB02KT TEMPO 0521/0523 27003G13KT= What wind is forecast for 2400 UTC?

. a) VRB04KT

. b) 11010KT

. c) VRB02KT

. d) 27003G13KT

7- In Refer to the following TAF extract;

. BECMG 0218/0221 2000 BR BKN004 PROB30 TEMPO 0221/0224 0500 FG VV001

. What does the abbreviation "PROB30" mean?

. a) Conditions will last for at least 30 minutes.

. b) Probability of 30%.

. c) The cloud ceiling should lift to 3000 FT.

. d) Change expected in less than 30 minutes.

8- What does the expression "Scattered (SCT)" mean?

. a) Nil significant cloud cover

. b) 3-5 Eights of the sky is cloud covered

. c) 5-7 Eights of the sky is cloud covered

. d) 3-4 Eights of the sky is cloud covered

9- Which of the following weather reports is a warning of conditions that could be potentially hazardous to aircraft in flight?

. a) SIGMET.

. b) SPECI.

. c) TAF.

. d) TREND.

10- In which weather report would you expect to find information about icing conditions on the runway?

. a) SIGMET

. b) AIRMET

. c) TAF

. d) METAR

11- What does the term METAR signify?

. a) A METAR is a warning of dangerous meteorological conditions within a FIR.

. b) A METAR signifies the actual weather report at an aerodrome and is generally issued in half-hourly intervals.

. c) A METAR is a flight forecast, issued by the meteorological station several times daily.

. d) A METAR is a landing forecast added to the actual weather report as a brief prognostic report.

12- The term PROB as used in a TAF message, indicates the probability in percentage, of phenomena described during a specific period.The numerical values immediately following the term PROB, are:

. a) 35 or 50

. b) 30 or 40

. c) 30 or 50

. d) 40 or 50

13- What does this mean in a weather chart

. a) moderate icing and severe turbulence between levels 140 and 180

. b) severe icing and turbulence between levels 140 and 180

. c) moderate icing and turbulence between levels 140 and 180

. d) severe icing and moderate turbulence between levels 140 and 180

14- Refer to the following TAF extract:BECMG 0118/0121 2000 BR BKN004 BECMG 0121/0124 0500 FG VV001

. What does the abbreviation "VV001" mean?

. a) Vertical visibility 100 m.

. b) Vertical visibility 100 FT.

. c) RVR greater than 100 m.

. d) RVR less than 100 m.

1- The actual change of temperature with height is known as:

. a) The environmental lapse rate.

. b) The adiabatic lapse rate.

. c) The temperature curve.

. d) The tephigram.

2- In a saturated atmosphere air which is forced to rise will:

. a) Tend to regain its former position if the ELR is less than the SALR.

. b) Tend to regain its former position if the ELR is greater than the SALR.

. c) Carry on rising if the ELR is less than the SALR.

. d) Classified as stable air when the ELR is greater than the SALR.

3- The DALR is greater than the SALR because:

. a) Saturated vapour pressure increases with increasing temperature.

. b) Convection is more active in dry than in moist air.

. c) The rate of cooling of saturated air is reduced by the release of latent heat of condensation.

. d) Because of the release of latent heat of evaporation.

4- Study the information given in the table below. If the air is forced to rise, the conditions most likely to lead to instability are given in which line? Temp.at 2000 ft Temp.at 5000 ft Relative Humidity

. a) +15ºC+10ºC50%

. b) +15ºC+10ºC100%

. c) +15ºC+11ºC100%

. d) +15ºC+12ºC50%

5- Which of the following statements is true?

. a) The tropopause is the dividing line between the stratosphere and the tropopause.

. b) Stability increases as the environmental lapse rate decreases.

. c) Heat is added to the environment by the evaporation of rain drops.

. d) High surface temperatures and a plentiful supply of moisture are the only conditions required for the development of thunderstorms.

6- When condensation takes place, the higher the temperature the the amount of latent heat .

. a) Lesser, released.

. b) Greater, absorbed.

. c) Greater, released.

. d) Lesser, absorbed.

7- The air is stable if:

. a) It moves very little.

. b) There are a few changes in pressure.

. c) When a lifting force is removed the air tries to return to its original position.

. d) When a lifting force is removed the air continues to rise.

1- The size of raindrops form a cloud is greater if:

. a) Air is stable and cloud is layer type.

. b) Air is unstable and cloud is heap type.

. c) Cloud type is AC or NS.

. d) The relative humidity is high.

2- In aerodrome reports and forecasts the height of the cloud base refers to:

. a) The height above mean sea level.

. b) The height above aerodrome elevation.

. c) The pressure altitude of the cloud base.

. d) The height above the average ground level for the area.

3- Low cloud in temperate climates have a base from:

. a) The surface to 6500 ft.

. b) 1000 to 6500 ft.

. c) The surface to 7500 ft.

. d) The surface to 7500 metres.

4- In temperate latitudes which statement is correct:

. a) Ci only occurs above 15000 ft.

. b) Ci only occurs above 16500 ft.

. c) Ci only occurs above 25000 ft.

. d) Ci only occurs above 30000 ft.

5- The turbulence associated with cumulus cloud is:

. a) Moderate.

. b) Slight to nil.

. c) Nil.

. d) Moderate possibly severe.

6- Which of the following clouds is never a hazard to aviation:

. a) Nimbostratus.

. b) Noctilucent cloud.

. c) Cumulonimbus cloud.

. d) Stratus cloud.

7- Clouds formed by convection will always:

. a) Be layer clouds.

. b) Be Cu CB or Ns.

. c) Have a rising cloud base and may develop into CB as the day progress.

. d) For only in Polar maritime air.

8- The movement of cool moist air over a warmer surface is likely to cause:

. a) Cumulus or cumulonimbus cloud.

. b) Advection fog.

. c) Nimbostratus cloud.

. d) Alto cumulus lenticular cloud.

9- Typical base heights in temperate latitudes, of altocumulus cloud are in the range of:

. a) 6500 ft to 23000 ft.

. b) 5000 to 15000 ft.

. c) 8500 to 18000 ft.

. d) 1000 to 6500 ft.

1- The type of precipitation in which visibility is likely to be most reduced:

. a) Drizzle.

. b) Snow.

. c) Light rain.

. d) Sleet.

2- The type of precipitation usually associated with shallow stratocumulus is:

. a) Mainly water droplets which can be supercooled if the temperature is low enough.

. b) Ice crystals.

. c) Supercooled water droplets only.

. d) Large water droplets due to strong up-currents associated with this type of cloud.

3- If there are small cumulus in the morning summer, it is reasonable to forecast in the day:

. a) Clear skies.

. b) St and drizzle.

. c) CB cloud.

. d) Haze.

4- The term “shower” implies that:

. a) Precipitation is in the form of rain and is continuous.

. b) Precipitation is from cumulonimbus cloud and lasts for short periods.

. c) Precipitation is intermittent and is from strato form cloud.

. d) Precipitation is continuous for long periods from cumuliform cloud.

5- The process by which water ice is transformed directly into vapour is known as:

. a) Sublimation.

. b) Supercooling.

. c) Supersaturation cloud.

. d) Radiation cooling.

1- An air mass that has travelled over an ocean is known as:

. a) Continental air and has a high humidity.

. b) Continental air and has a low humidity.

. c) Maritime air and has a high humidity.

. d) Maritime air and has a low humidity.

2- Characteristic weather associated with a Pm airmass transitting Europe in summer would include:

. a) Widespread Cu and Cb activity overland during the day.

. b) Clear quiet settled weather overland by day with good visibility.

. c) Warm moist conditions with some Sc or Cu and moderate to poor visibility.

. d) Extensive low stratus cloud giving drizzle to light rain overland by day.

3- With a cold occlusion:

. a) The air ahead of the warm front is colder than the air behind the cold front.

. b) The warm sector remains on the surface.

. c) The cloud type is predominately layer with a wide precipitation band.

. d) There is a risk of CB embedded in NS.

4- The average upper winds at A1, B1 and C1 in Appendix 'A' are respectively:

. a) Easterly, westerly, northwesterly.

. b) Northwesterly, westerly, southwesterly.

. c) Southwesterly, westerly, norhwesterly.

. d) Southwesterly, westerly, northerly.

5- The average surface level winds at A3, B3 and C3 in the following figure are respectively:

. a) Easterly, westerly, southwesterly.

. b) Westerly, westerly, southwesterly.

. c) Southwesterly, westerly, northwesterly.

. d) Southwesterly, westerly, westerly.

6- If air transit is heated from below it tends to become more:

. a) Stable.

. b) Neutrally stable.

. c) Unstable.

. d) None of this.

7- When a cold front passes a station in Spain:

. a) The wind veers and the temperature falls.

. b) The wind backs and the temperature falls.

. c) The wind veers and the temperature rises.

. d) The wind backs and the temperature rises.

8- The front in the picture is a:

. a) Warm occlusion

. b) Cold occlusion

. c) Warm front

. d) Cold front

9- How do air masses move at a warm front?;

. a) Cold air overrides a warm air mass.

. b) Warm air overrides a cold air mass.

. c) Cold air undercuts a warm air mass.

. d) Warm air undercuts a cold air mass.

1- On a day in summer with a slack pressure gradient, an airfield on the south coast of England has a surface W/V of 080/06 at dawn. The coast/line is in an East/West direction. The most probable W/V at noon would be:

. a) 360/12.

. b) 080/12.

. c) 180/12.

. d) 080/06.

2- When a Fohn wind occurs:

. a) There are unstable conditions on the downwind side of the mountain.

. b) Air is cooled mainly at the DALR on the upwind side of the mountain and is heated at the SALR on the downwind side.

. c) Windspeed must be at least 15 kt at the surface increasing with height and maintaining direction.

. d) Air is cooled mainly at the SALR on the upwind side of the mountain and is heated mainly at the DALR on the downwind side.

3- The geostrophic wind blows:

. a) Parallel to curved isobars.

. b) When pressure values are changing rapidly.

. c) In a tropical revolving storm.

. d) When geostrophic force and pressure gradient force are equal.

4- A Katabatic wind can result in:

. a) An increase in temperature.

. b) Fog in the valley at night.

. c) Thunderstorms in summer.

. d) Stratus cloud.

5- A strong wind that rises suddenly, lasts for some minutes and dies comparatively suddenly away is called:

. a) A gust.

. b) A squall.

. c) A gale.

. d) A blast.

6- A ravine or valley wind:

. a) Is a wind blowing at increased speed along a valley.

. b) Is a wind blowing from a hill to a valley below.

. c) Is a wind blowing up a hill from a valley.

. d) Is a wind blowing at reduced speed along a valley.

7- Which of the following is true of a land breeze?

. a) it blows only at noon

. b) it blows from land to water

. c) it blows from water to land

. d) it blows by day

8- What characteristics will the surface winds have in an area where the isobars on the weather map are very close together?

. a) Strong and flowing across the isobars.

. b) Very weak but gusty and flowing across the isobars.

. c) Moderate and flowing parallel to the isobars.

. d) Strong and flowing parallel to the isobars.

9- A point is between two isobars. The pressure gradient is 1 Pa/km between them. The latitude at this point is 45ºN and the air density is 1,06 kg/m3. Calculate the geostrophic wind at this point.

. a) 17 km/h.

. b) 33 km/h.

. c) 51 km/h.

. a) 19 km/h.

1- Which of these cloud types can't be observed in the water vapour channel?

. a) Cumulus humilis.

. b) Cumulonimbus capillatus (anvil cirrus)

. c) Cirrus.

. d) Cumulus humilis and cirrus.

2-Cumulonimbus an cirrus occur at levels detectable by the water vapour channel. Low stratus and cumulus humilis are at too low a level in the atmosphere to be detected.Which of these cloud types can be viewed in the visible channel?

. a) Cirrus and cumulonimbus.

. b) Cumulus.

. c) Low stratus.

. d) All of them.

3- What is the smallest distinguishable feature that can be seen in the Meteosat visible channel?

. a) 1.0 km

. b) 2.5 km

. c) 7.5 km

. d) 10.5 km

4- What is the cone of silence? (Choose the best answer.)

. a) The volume under the lowest elevation of the beam

. b) The volume above the highest inclination angle of the beams

. c) The volume between the lowest and highest scans in clear air mode

. d) The volume between the lowest and highest scans in precipitation mode

5- In which of the following instances would precipitation often go completely unobserved by radar due to the geometry of the radar beam?

. a) A tall thunderstorm producing rain very close to the radar

. b) A tall thunderstorm producing rain about 50 km away from the radar

. c) A low, stratiform cloud producing rain near the radar's maximum unambiguous range and a thunderstorm producing rain behind a mountain located 10 km from the radar.

. d) None of them.

6- What usually doesn't constitute ground clutter that we often see near a radar?

. a) Insects

. b) Birds

. c) Large particulate matter, like dust

. d) Fog

7- Which of the following phenomena appears on radar as evenly scattered bands of weak reflectivity or ripples near the radar, especially during the afternoon? (Choose the best answer.)

. a) Smoke

. b) Chaff

. c) Horizontal convective rolls

. d) Anomalous propagation

8-Horizontal convective rolls usually appear on radar on mostly clear days with strong surface heating and a fairly steady wind direction. Their circulations concentrate particulate matter and insects, making them visible to radar.

9- Weather satellites measure radiation emitted by the Earth or reflected solar radiation

. a) They are usually passive detection devices.

. b) They are usually active detection devices.

. c) They are usually none of them.

. d) They are usually both of them.

1- The conditions which must exist to allow thunderstorms to develop are:

. a) A trigger action, a plentiful supply of moisture and a very stable atmosphere.

. b) A steep lapse rate, a stable atmosphere through a large vertical extent and a plentiful supply of moisture.

. c) A plentiful supply of moisture and a steep lapse rate through a large vertical extent and a trigger action.

. d) A steep lapse rate through a large vertical extent, a low relative humidity and a trigger action.

2- Hazards of the mature stage of a TS cell include lightning, turbulence and:

. a) Microburst, windshear and anvil.

. b) Icing, microburst and windshear.

. c) Icing, drizzle and microburst.

. d) Windshear, hail and fog.

3- During the stage of a thunderstorm cell, the cloud contains.Complete the above statement correctly using one of the following:

. a) Building / up currents and down currents.

. b) Mature / up currents and down currents.

. c) Dissipating / up currents and down currents.

. d) Building / down currents only.

4- The following is unlikely to be a hazard below a thunderstorm:

. a) Severe turbulence.

. b) Severe icing.

. c) Windshear.

. d) Large variations in pressure setting values.

5- Thunderstorms are likely if:

. a) Air is unstable, there is sufficient water vapour and there is a trigger action.

. b) Air is completely stable, there is sufficient water vapour and there is lifting orographically.

. c) There is a warm front.

. d) There is a col in winter.

6- Hail grows by:

. a) Freezing as it leaves the cloud.

. b) By up and down progress in CU cloud.

. c) By collision with supercooled water drops.

. d) By collision with ice crystals.

7- How long approximately does a Cumulonimbus cell take to complete the full cycle from the Cumulus (building) to dissipating stage?

. a) 2-3 hours.

. b) 1-2 hours.

. c) 4-5 hours.

. d) About 1 hour.

8- A microburst usually lasts for and is about across.

. a) 20 minutes 20 nm

. b) 5 minutes 5 km

. c) 30 minutes 10 nm

. d) 45 minutes 5 nm

9- When flying throug an active CB cloud, lightning strikes are most likely:

. a) Above 5000' and underneath the anvil.

. b) In the clear air below the the cloud in rain.

. c) In the temperature band between +10ºC and -10ºC.

. d) At about 10000 ft above AMSL.

1- Maximum turbulence associated with the standing waves is likely to be:

. a) Two wavelengths down wind and just above the surface.

. b) Approximately one wavelength down wind of, and approximately level with, the top of the ridge.

. c) Just below the tropopause above the ridge.

. d) Down the lee side of the ridge and along the surface.

2- For the formation of mountain waves, the wind above the level of the ridge should:

. a) Decrease or even reverse direction.

. b) Increase initially, then decrease.

. c) Increase with little change in direction.

. d) Increase and then reverse in direction.

3- When flying in IMC in a region close to a range of hills 2000 ft high, in stable air and with wind direction at right angles to the axis of the range of hills, which of the following is probably the most dangerous practice:

. a) Flying towards the hills, into the wind, at flight level 65.

. b) Flying parallel to the hills on the downwind side at flight level 40.

. c) Flying towards the hills downwind at flight level 55.

. d) Flying parallel to the hills on the upwind side at flight level 40.

4- Which of the following statements referring to Jet Strems is correct:

. a) CAT associated with jet streams is probably associated with the rapid wind shear in the vicinity of the jet.

. b) The maximum wind speed in a Jet Stream increases with increase of height up to the tropopause and remains constant thereafter.

. c) The core of a Jet Stream is usually located just below the tropopause in the colder air mass.

. d) The rate of change of wind speed at any given level is usually greatest on the warmer side of the jet.

5- Flight conditions at B1 are likely to be:

. a) Smooth.

. b) Turbulent.

. c) Turbulent in breaking wave crests.

. d) Turbulent due to marked up and down currents.

6- The most extreme turbulence can occur:

. a) At B1.

. b) At A2.

. c) At ABC 3.

. d) At B2, 3, 4 and C2, 3, 4.

7- Clear air turbulence, in association with a polar front jet stream in the Northern Hemisphere, is more severe:

. a) Underneath the jet core.

. b) In the center of the jet core.

. c) Looking downstream on the right hand side.

. d) Looking downstream on the left hand side.

8- CAT should be reported whenever it is experienced. What should be reported if the aircraft remains in positive control at all times, crew and passengers feel a definite strain against their seat or shoulder traps, food service and walking is difficult

. a) Light CAT.

. b) Extreme CAT.

. c) Severe CAT.

. d) Moderate CAT.

1- At temperatures of between 0ºC and -10ºC clouds consist of:

. a) Entirely water droplets.

. b) Entirely ice crystals.

. c) Mostly water vapour.

. d) Mostly supercooled water droplets and a few ice crystals.

2- Turbulent clouds are most serious from the icing standpoint because:

. a) Strong vertical currents mean that a predominance of large supercooled water droplets will be present.

. b) Strong vertical currents mean that a predominance of small supercooled water droplets will be present.

. c) Turbulent clouds produce hail which sticks to the aircraft.

. d) Turbulent clouds indicate a low freezing level.

3- Hoar frost forms on an aircraft when:

. a) The aircraft suddenly enters a cloud at below freezing temperature.

. b) The aircraft in sub zero clear air suddenly enters a colder region.

. c) The aircraft in sub zero clear air suddenly enters a warmer moist region.

. d) The aircraft suddenly enters a cloud which is at higher temperature than the surrounding air.

4- Stratus cloud of limited depth at a temperature of -5º C will most likely give:

. a) Moderate to heavy rime ice.

. b) Moderate to heavy glaze ice.

. c) Light to moderate rime ice.

. d) Light to moderate glaze ice.

5- Most cases of serious piston engine icing occur in cloud, fog, or precipitation with a temperature range between:

. a) -10º Cto+25ºC.

. b) -18º Cto+5ºC.

. c) -10ºCto0ºC.

. d) -20ºCto+15ºC.

6- Clear ice forms as a result of:

. a) Large supercooled water droplets spreading as they freeze.

. b) Ice pellets splattering on the aircraft.

. c) Small supercooled water droplets splashing over the aircraft.

. d) Water vapur freezing to the aircraft.

7- Orographic uplift in stable conditions gives a strong vertical component to air movement thus supporting larger supercooled droplets in orographically formed cloud. Consideration should also be given to the fact that in this cloud:

. a) The 0ºC isotherm will be higher.

. b) The 0ºC isotherm will be lower.

. c) The lapse rate will be isothermal.

. d) An inversion can be anti-cyclonic.

8- Carburettor icing is unlikely:

. a) In cloud.

. b) At temperatures between -10ºC and -30ºC.

. c) In clear air.

. d) When the RH is 60%.

9- Flying 50 nm ahead of a warm front out of cloud at 1000 ft in winter, with an ambient temperature of -8ºC, there is a strong risk of:

. a) Hoar frost.

. b) Rime icing and carburettor icing.

. c) Structure damage caused by hail.

. d) Clear ice in the form of rain ice.

10- In AS cloud at FL 170 and a temperature of -20ºC the airframe icing most likely to be experienced is:

. a) Moderate clear icing.

. b) Light rime icing.

. c) Hoar frost.

. d) Severe clear icing.

1- A thermal depression is likely to form:

. a) Over the Iberian Peninsula during the summer.

. b) In the lee of the Alps over Northern Italy in winter.

. c) In association with a marked trough of low pressure over the USA.

. d) On the trailing side edge of a warm sector mid latitude depression.

2- Tropical revolving storms usually:

. a) Form close to one side of the equator and while moving slowly in a westerly direction, cross over to the other hemisphere.

. b) Move in a westerly direction before recurving towards the equator.

. c) Move in an easterly direction before recurving towards the farthest pole.

. d) Do not form within 5º of the equator.

3- With reference to tropical revolving storms, which of the following statements is correct:

. a) Typhoons are found in the South China in January.

. b) Cyclons, occur in the Bay of Bengal in winter.

. c) Hurricanes, in the South Atlantic sometimes affect the east cost of Brazil.

. d) Hurricanes affect the south east of the USA in late summer.

4- Extensive cloud and precipitation is often associated with a non-fontal thermal depression because of:

. a) Surface divergence and upper level convergence causing widespread descent of air in the depression.

. b) Surface convergence and upper level divergence causing widespread descent of air in the depression.

. c) Surface convergence and upper level divergence causing widespread ascent of air in the depression.

. d) It is the name given to a line of thunderstorms that lie along the ITCZ but some 200 miles to the south.

5- Tropical Revolving Storms:

. a) Are always given a male first name beginning with “A” for the first of the season and thereafter named in alphabetical order of occurrence.

. b) Have internal wind speeds of 10-20 knots rotating cyclonally round a subsiding clear core known as the eye.

. c) Usually have the most severe weather in the quadrant to the right of the track in a Hurricane in the North Hemisphere.

. d) Regenerate after crossing the coast from sea to land.

Crear Test

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