The Atmosphere - Chapter 4: Fronts Flashcards
Boundaries that separate air masses of different densities, one warmer and often higher in moisture content than the other
Front
Fronts can form between any two _____
contrasting air masses
Above the ground, the frontal surface slopes at a low angle so that ___ air overlies ___ air
warmer
cooler
In the ideal case, the air masses on both sides of the front move _______
same direction
same speed
Most of the time, one of the sides of air is moving ____ in the direction perpendicular to the front than the airmasses on the other side
faster
What happens as one air mass moves into another?
Some mixing along the frontal happens, but air masses generally retain identity. One air mass is displaced upward over another.
Which of the air masses advancing will be forced aloft?
The warmer, less dense air mass
The cooler, denser air acts as the ___ upon which lifting takes place
wedge
What is a warm front?
When the surface position of a front moves so that warm air occupies territory formerly covered by cooler air
What do warm fronts generally produce?
Several hours of moderate to gentle precipitation over a large region
On some occasions when the overturning air is unstable and the front is rather sharp warm fronts might produce
Thunderstorms
Cumulonimbus clouds
True or false: mackeral scales and mares’ tails make lofty ships carry low sails
True
What happens to the temperature with the passage of a warm front?
A gradual increase in temperature
This type of front takes place when cold air is actively advancing into a region unoccupied by warmer air
cold front
On average, how much steeper are cold fronts than warm fronts?
twice
