Heating and cooling

Question 1

The sun’s radiation heats the earth which in turn heats the air at low levels mainly by…

Answer 1

Conduction

Question 2

Coastal areas experience much small temperature extremes compared to continental areas because…

Answer 2

water warms and cools more slowly than land

Question 3

What is the term used to describe the temperature change when air descends a mountain range?

Answer 3

compression warming

Question 4

A cloudy day is usually cooler than a clear day because…

Answer 4

solar radiation is reflected by the clouds

Question 5

Two ways of cooling the atmosphere that do not involve vertical motion are…

Answer 5

Evaporation & Advection cooling

Question 6

Cold air moving over a warm surface results in…

Answer 6

advection warming

Question 7

Once the air has been heated in the low levels the heat can be spread aloft by…

Answer 7

convection and turbulent mixing

Question 8

Subsiding dry air compresses and heats up at a rate of…

Answer 8

3.0 Celsius / 1000 feet

Question 9

Define Lapse rate

Answer 9

The rate at which Temp changes with height in the atmosphere

Question 10

Define ELR (environmental lapse rate)

Answer 10

The rate of Temp change with height at any particular time and place

Question 11

Describe the essential difference between the ELR and the adiabatic lapse rates.

Answer 11

DALR and SLAR are thermodynamics values for air which is forced to ascend or descend & the ELR is the actual lapse rate which exists in a static atmosphere.

Question 12

The cooling of the air by radiation means that the air is..

Answer 12

in contact with a surface which is cooling by radiation

Question 13

The temperature will be warmest at night over land when the surface wind speed is…

Answer 13

strong

Question 14

Conditions for lowest morning temperature due to radiation cooling are …

Answer 14

light winds, clear, low lying land areas

Question 15

When air rises, it cools due to…

Answer 15

expansion

Question 16

When unsaturated (dry) air rises 3000’ in the atmosphere its temperature is..

Answer 16

decreasing, -9 Celsius

Question 17

Air at surface has a temperature of 20 and dew point of 17 (20/17). If it rises 2000’, what will its temperature be at 2000’? (consider effect of condensation)

Answer 17

0' = 20/17
1000' = 17/17
2000' = 15,5/15,5

Question 18

What does advection warming will result for aircrew?

Answer 18

low level turbulence

Question 19

When air cools by moving over a colder surface, it is called..

Answer 19

advection cooling

Question 20

The air LOSES/GAIN heat when evaporation of water takes places, which causes the air to be COOLED/WARMED

Answer 20

LOSES & COOLED

Question 21

List and briefly describe 5 lifting processes which causes expansion cooling

Answer 21

1. Orographic lift: Air flows up over a hill or mountain, expands and cools, forming clouds and precipitation
2. Mechanical Turbulence: Wind blowing over rough terrain causes vertical currents, air cools as it’s lifted and can form clouds
3. Convection: Air heated by the ground will rise an cool. Clouds may result with right conditions
4. Low level convergence: Wind blowing toward a point or line is called a converging wind. Air has to go somewhere (Goes UP)
5. Frontal Lift: Fronts causes extensive areas of large scale ascent