Precipitation
What are three forms of precipitation and what causes precipitation to fall?
Rain, Hail, Snow, (sleet)
Precipitation falls due to gravity and when Up Drafts are not strong enough to keep it in clouds.
What percentage does humidity need to be at to create a large storm?
100%
Air pressure always travels from areas of ___ pressure to _____ pressure.
High pressure to low pressure
What is Evaporation?
When water (liquid) turns into water vapor (gas)
What is the process for rain?
Warm air rises to colder air above carrying water vapor. The water vapor slows down and attaches to a CCN in the sky, condensing (turning it into water). What the rain is too heavy for updrafts, gravity pulls it down.
Other than humidity, what else do we need a lot of in the sky to create a Big Storm?
CCN’s. Cloud condensing nuclei. Which can be dirt dust, ash, pollen, salt.
When there is a High Air Pressure Area (higher pressure at the center than the areas around it), air near the surface flows ______ and _______.
down and away.
What is condensation?
When water vapor slows down and turns into a liquid on a cold surface
What is the process for hail to form, and build?
Warm air rises to colder air above carrying water vapor. The water vapor slows down and attaches to a CCN in the sky, condensing (turning it into water). Updrafts bring the water above the freezing line inside the cloud and the water freezes. What the hail is too heavy for updrafts, gravity pulls it down. If another updraft catches it, the hail combines with rain and freezes when it goes above the freezing line. Hail can also combine with supercooled water above the freezing line. Then falls when it is too heavy due to gravity.
What should the temperature difference be between the ground and higher up in the atmosphere for a large storm? And where should the warm weather be?
There should be a really large temperature difference with the warm air towards the ground and cold air towards the sky to be conducive for condensation
When there is a Low Air Pressure area (lower pressure at the center than the areas around it), air near the surface flows ______ and _______.
up and together (towards the center).
What is transpiration?
When water inside plants, grass and trees evaporates.
How does snow form (after water vapor evaporates)?
The water vapor slows down and attaches to a CCN in the sky, instantly turning it into an ice crystal. When the snow is too heavy for updrafts, gravity pulls it down.
What is the convection cycle, and how does it connect to a storm?
The convection cycle is when warm air rises, and cold air sinks, and this process repeats, creating large winds and bringing humidity and water vapor into the sky.
My barometer's balloon is pushing up, causing the popsicle stick to lower. What type of air pressure does this mean the area has, and what type of weather could be expected outside?
low air pressure, lots of clouds / condensation in the air.
What drives the water cycle?
Energy from the sun
How do we get spiky hail vs. smooth hail?
To get spiky hail, it has to form with super cold water above the freezing line inside a cloud. To get smooth hail, cold water has to form with hail inside the cloud. Then, they need to be brought up over the freezing line long enough to refreeze.
What are 5 components needed for a large hail storm to happen, and what would the clouds look like?
Very warm ground and very cold upper atmosphere.
Strong Updrafts
CCN’s
100% humidity
Freezing line in the cloud
The clouds would be very large, very tall, and very dark, at least towards the bottom of the cloud, blocking the sunlight
How does the air pressure differ at the top of a high mountain vs at sea level?
Higher altitudes have a lower air pressure.
Explain the water cycle, starting with energy from the sun, as two paths, one with precipitation and one without precipitation. Including vocabulary in each step.
The sun heats the ground via radiation. The water vapor in the air warms up via conduction from the grounds energy. Water vapor can also come from bodies of water and plants (transpiration). The warm water vapor rises because it is less dense than the air around it, carrying the water vapor high in the atmosphere. As the water vapor loses energy, it starts to cool down and condenses with CCNs. Then gravity pulls down the precipitation to the ground, repeating the water cycle. If conditions aren’t conducive for condensation then the water vapor will fall, staying as a gas.