Atmospheric Stability Flashcards
When a parcel of air becomes saturated and condensation occurs -
latent heat is released
Relative humidity is
the percentage degree of saturation
When water droplets in the liquid state freeze -
Latent heat is released
The dew point is the temperature-
to which a sample of moist air must be cooled at constant pressure for it to become saturated
A parcel of air has a temperature of +15 degrees C and a relative humidity of 80%. A temperature rise of 10 degrees C will cause -
the relative humidity to decrease
Relative humidity is measured using a -
Psychrometer
The water vapour held in saturated air is-
invisible always
When the temperature and dew point are the same -
the relative humidity is 100%
The reading of wet and dry bulb thermometers at meteorological stations serves to calculate -
humidity
Relative Humidity is the -
ratio of the amount of water vapour present to the amount that could be held in a samble of air
When the air temperature at a particular level is higher than that existing at a lower level -
a n inversion exists
Warm air is rising adiabatically above a ploughed field, surface temperature +21 degrees C. The dew point at the cloud base is +3 degrees C.
The cloud base and freezing level respectively are approximately -
6000 ft and 8000 ft
If the ELR is between 1.5 degrees C and 3 degrees C the air is -
stable for dry air and unstable for saturated air
Above the condensation level the lapse rate of rising air will -
A reduce from the dry adiabatic lapse rate to the smaller saturated adiabatic lapse rate
An inversion results in -
extremely stable conditions above
04 Warmer temperatures above a colder layer of air indicates -
an inversion
When the ELR is greater than the DALR, dry air is -
unstable
The dry adiabatic lapse rate is -
3 degrees C/1000 ft
When the SALR is greater than the ELR, saturated air is -
stable
The actual change of temperature for an increase in altitude is known as -
the environmental lapse rate
Warm air is rising adiabatically above a ploughed field, surface temperature +21 degrees C. The surface dew point is +3 degrees .C Allowing for the dew point lapse rate, the cloud base and freezing level respectively are approximately -
7500 ft and 7000 ft
The average rate of decrease in temperature per 1000 ft of height is approximately -
2 degrees C
An Adiabatic process is one-
in which no heat is transferred into or out of the system
A met station shown on the diagram, is located on the leeward side of a coastal range. From the data given, the MSL temperature on the windward side of the range using DALR &SALR is - See Q12 rev test 6
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