The Atmosphere Flashcards
What is the lowest portion of the earth’s surface?
Troposphere
What happens to temperature in the troposphere?
Decreases with altitude
Where is the majority of water vapour, clouds and weather found?
Troposphere
What is the tropopause?
Boundary where the temperature no longer decreases with height
The altitude and temperature of tropopause?
Approximately 26,500ft (8km) and a temperature of -40 degrees over the poles
AND
59,500ft (18km) and a temperature of -70 degrees over the equator
Is the temperature constant in the lower levels of the stratosphere?
Yes, it is called the isothermal layer
In the upper stratosphere what occurs with increasing height?
The temperature rises due to the presence of ozone
What is an inversion?
When temperature increases with height instead of decreases
What does ISA stand for?
International Standard Atmosphere
What is the standard environmental lapse rate?
0ft- 36,090ft is 1.98 (Rounded to 2)
Height of ISA tropopause?
36.090ft AMSL
What is the ISA temp for mean sea level?
15 degrees
What is the ISA tropopause temperature?
-56 degrees
What are the three ways in which heat can be transferred?
- Radiation
- Conduction
- Convection
What is radiation?
Transfer of heat by electromagnetic waves
The hotter the body, the ….. the wavelength
Shorter
The sun is extremely hot and emits very short wave radiation also known as….
Insolation
The earth’s surface is much cooler and emits longwave radiation also known as…
Terrestrial
What is conduction?
Transfer of heat through contact
What is convection?
Transfer of heat through the movement of a body, usually vertically
What is the horizontal movement of air called?
advection
What is the greenhouse effect?
Due to the longer wavelength of terrestrial radiation; it is more easily absorbed by water vapour and carbon dioxide. Their molecules then radiate heat back to the earth.
What does the temperature of the surface depend on?
- Reflectivity of the surface
- Conductivity of the surface
- Specific heat of the surface
- Cloud cover
What does diurnal mean?
24 hour or daily variation
What are isotherms?
Lines on a weather map joining places having the same temperature
When is peak temperature reached?
2pm-3pm
When is the lowest temperature?
Around Dawn
Do inland or coastal locations have greater diurnal variation?
Inland
Why do inland locations have greater diurnal variation?
The high specific heat of the ocean keeps coastal temperatures cooler during the day and warmer at night. Inland the atmosphere heats up more during the day and cools off more during the night.
Will wind reduce or increase diurnal variation?
Reduce
Does cloud cover increase or decrease diurnal variation?
Reduce
