Meterology Flashcards
Clouds and what-not ;)
Define: Orographicn lift
Air moving up a sloping terrain, such as a moutian side, will continue upward movement especially if unstable
Define: Stratus cloud
forms in horizontal layers and usually forms as a layer of moist air is cooled below its saturation point
Does a land breeze blow at day or night?
Night, land cools and air above cools in turn, the warmer air over the water rises and cool air moves from land to sea to fill in.
The ICAO standard atsmophere is________
pressure-29.92”Hg
Tempurature-15C
Lapse rate-1.98C/1000’
Define: Occlusion
cold air mass catches up with onesself lifting the warmer sector entirely off the ground
Define: Warm front
A mass of warm air advancing on a retreating mass of cold air
List the different types of fog-5
1) Radiation-ground cooled at night, air above ground also cools, if air is moistand cooled below saturation pointfog forms
2) Advection fog-warm damp air blows over cold surface
3) Upslope fog-air cooled by expansionas moves up
4) Steam fog-cold air passes over warm water, evaporation occurs until air is saturated
5) Ice fog-extremely cold tempuratures, fuel combustion and moisture to air
In standard atsmophere the tempurature at 5000’ would be?
5*C
Define Cumuloform clouds
forms in rising air currents and are evidence of unstable air conditions
Define: Pressure altittude
The reading on the altimeter when it is set to standard barometric pressure
During a descent from 200’ AGL to the surface, you will usually find that the winds; Veer/back, increase/decrease?
Back and decrease
Define: Trowal
wedge shaped mass of air overlying an occluded front
Name the different types of high and low clouds
high: Cirrus(Ci)
Low: Alto
what are the two main forces affecting movement of upper level winds?
1) pressure gradient- forces air horizontal from an area of high to low pressure
2) Coriolis force-deflects the flow of air cuasing it to flow parrelel to isobars
* Coriolis force deflects to the right in the northern hemisphere
Define: Sublimation
heating of ice crystals changing them to invisible gas without passing through the visible water droplet stage
what invisible gases is the atsmophere composed of?
78% nitrogen
21% oxygen
1% other(argon, carbon dioxide etc.)
Are areas of convergence or divergence more favourable to the occurence of precipitation in form of thunderstorms rain hail or snow.
Convergence
Define: Isobars
located on a weather map, lines that join areas of equal barometric pressure at 4 millibar intervals
the cloud type usually associated with steady rains is___________.
Nimbostatus
How do condensation nuclei affect cloud formation
condensation nuclei are reguired for water droplets to form
What type of cloud should be avoided because of its turbulence, the danger of heavy icing and violent electrical activity?
Comunolimbus
Define: Absolute altitude
Actual height above earths surface
Atsmophere Consists of 4 distinct layers list in ascending order.
troposhpere
statosphere
mesosphere
thermosphere
Define: Advection
A flow of air that movess from acold area over a warm area will be heated in its lower layers by the warm earth over which it is flowing
What are the principle air masses?
Continental Arctic (cA) Maritime Arctic (mA) Continental Polar (cP) Maritime Polar (mP) Continental Tropical (cT) maritime Tropical (mT)
Define: Divergence
A flow of air outwards from an area
Define: Cold front
a mass of cold air overtaking warmer air
Define: Trough
an elongated U-shaped area of low pressure with higher pressure on either side
How many oktas of the sk are covered in the following: Clear\_\_\_\_\_\_ Few\_\_\_\_\_\_\_\_ Scattered\_\_\_\_\_\_\_\_\_\_ Broken\_\_\_\_\_\_\_\_\_ Overcast\_\_\_\_\_\_\_\_
Clear-no clouds Few-2 or less Scattered-3 to 4 Broken- 5 to 7 Overcast- 8
Define: Frontolysis
a front which is decreasing in intensity
Define: Geostraphic winds
wind that flows parralel to isobars
Define: Expansion
on account of rising air it expands and in results in cooling
Define: Frontogenesis
A front which is increasing in intensity
Define: Convergence
the flow of air into an area is usually accompanied by an upward movement of air to permit the excess accumulation of air to escape
Name the different types of low and vertical clouds
Low: Stratus
Vertical: Cumulus
Define: Density altitude
Pressure altitude corrected for tempurature
