Atmospheric Lifting Mechanisms

Question 1

What is an air mass?

Answer 1

a distinct body of air that has taken on the moisture/temperature characteristics of its source region

Question 2

convergent lifting

Answer 2

*air flowing from different directions into the same low-pressure area, displacing air upward all along the equatorial region

the southeast and northeast trade winds converge, forming the ITCZ and other areas of extensive convergent uplift, towering cumulonimbus clouds, and high average yearly precipitation

Question 3

convectional lifting

Answer 3

*when an air mass gains continentality, it heats by convection over the warmer land surface

if conditions are unstable, initial lifting continues and cirrostratus clouds develop along with increased likelihood of precipitation
–> convectional ground heating leads to convectional rain with higher humidity

Question 4

orographic lifting

Answer 4

*when an air mass is forcibly lifted upslope as it is pushed against a mountain, cooling the air adiabatically

stable air –> stratiform clouds
unstable air –> cumulus and cumulonimbus clouds

Question 5

frontal lifting

Answer 5

*when an air mass is displaced upward along the leading edges of the contrasting air masses
cold front=the leading edge of a cold air mass
warm front=the leading edge of a warm air mass
–> highest potential for extreme weather like hail, tornadoes, hurricanes, etc.