Exam 17: Moisture, clouds, and Precipitation

At 25°C it takes 20 grams of water vapor to saturate 1 kilogram of dry air.If there are 5 grams of water vapor in 1 km of air at that temperature,what is the relative humidity?

Relative humidity is usually expressed as a percent.

On a given day in the winter in St.Louis,Missouri,it began snowing in the morning,the snow changed to rain by noon,later in the afternoon sleet was falling which turned to snow,and by evening rain was freezing on bridges and roadways as glaze.Briefly explain how such a sequence of precipitation might occur.

Which of the following is the most useful measure of water vapor in the air?

The dew point is the temperature at which ________.

If 2 grams of water absorbs 20 calories of heat,the resulting water temperature change is ________.

A wintertime form of precipitation that consists of small ice particles is called ________.

This cloud sometimes produces "mare's tails."

The term used to describe clouds that consist of globular masses that take on a billowy form is ________.

The process of converting a liquid to vapor is termed ________.

Clouds form because rising air cools as it comes in contact with colder air aloft.

When air sinks,it compresses and warms.

Condensation nuclei,tiny particles of matter in the air,are important because ________.

When air is unstable,the environmental lapse rate is ________.

Thunder and lightning are associated with these clouds.

When supercooled raindrops freeze on contact with solid objects,________ forms.

A wintertime form of precipitation that consists of small ice particles is called ________.

The ________ is the temperature to which a parcel of air would need to be cooled in order to reach saturation.

________ wedging occurs when warm air is forced over cooler air.

Because the mixing ratio is expressed in units of mass,it is affected by changes in pressure or temperature.