Download AIM: Clouds 1. Clouds form as warm air rises and cools and water

AIM: Clouds
1. Clouds form as warm air rises and cools and water vapor condenses
into water droplets, which collect to form clouds.
2. Clouds can be classified according to their shapes and altitudes.
Clouds can be found at the following altitudes:
A) High clouds - more than 6,000 m (19,700 ft.)
B) Mid-level clouds - 2,000 - 6,000 m (6,600 to 19,700 ft.)
C) Low clouds - under 2,000 m (6,600 ft.)
D) Cumulonimbus clouds are higher than 10,000 m (32,800 ft.)
3. When clouds form, the water droplets don't immediately fall to the
ground because the droplets are so small and light that they float in
the air.
4. Three different types of clouds:
1) Cumulonimbus - a piled-up cloud that brings rain
2) Cirrostratus - a sheet-like mass of curled clouds
3) Nimbostratus – sheet-like clouds that bring rain
5. Cirrus clouds differ from stratus clouds because cirrus clouds are
high, wispy clouds that are made of ice crystals, while stratus clouds
are low, even sheets that are made of water droplets.
6. Thunderstorms are most often associated with cumulonimbus clouds.
AIM: Learn what causes different types of precipitation
1. When ice crystals within clouds become too heavy, they fall as
precipitation.
2. As ice crystals fall toward the ground, the temperature of the
different bands of air they pass through determines the kind of
precipitation that falls on the surface: rain, snow, sleet, hail, or
freezing rain.
3. Sleet forms when ice crystals melt to form raindrops but refreeze
on the way down.
4. Freezing rain forms from drops that fall and freeze the moment they
hit something.
5. If ice crystals falling from clouds fall through air that is cold enough,
they reach the ground as snow.
6. How does hail form?
- Pellets of ice form as air currents toss ice crystals up and down
within a cumulonimbus cloud. Water collects on a crystal as it moves up
and down with strong air currents in the cumulonimbus clouds and
freezes as it rises in the cloud. When the pellet becomes too heavy, it
falls to the ground.