Exam 7: Precipitation

The next improvement for Doppler radar is called the ____________________. This form of Doppler radar, which has been installed around the United States over the last several years, transmits both a vertical and horizontal pulse, which makes it easier to determine whether falling precipitation is in the form of rain or snow.

In calm air,a typical cloud droplet falls over 600 times faster than a typical raindrop.​

Condensation onto hygroscopic nuclei is possible at relative humidities less than 100 percent due to the​

Very small cloud droplets of pure water can evaporate even when the relative humidity is 100 percent.

The lightest form of rain is​

A warm stratus cloud is typically less than 500 m thick and has slow upward air movement (generally less than 0.1 m/sec).​

In dry powdery snow,the water equivalent ratio may be as high as​

The primary method used in preventing the growth of large,destructive hailstones is to inject a thunderstorm with large quantities of​

In various parts of the world where the air is typically moist but rainfall is scarce,_____________________ are used to gather fresh water.

Is silver iodide used as a cloud seeding agent in warm or cold clouds? Why is it the most commonly used cloud seeding agent?

List the common precipitation gauges that measure rain and snow,and explain their principles.

Heavy showers usually fall from ____________________clouds,whereas steady precipitation normally falls from ____________________clouds.​

What is the main difference between a raindrop and a cloud droplet?

Which cloud would most likely produce drizzle?​

A common term used for saturation vapor pressure when referring to cloud droplets is ____________________ vapor pressure.​

Generally,the concentration of nuclei is less over the oceans than over land.​

When the temperature in a cloud is -30°C,larger cloud droplets are more likely to freeze than smaller cloud droplets.

Radar stands for ____________________.​

List and describe three ways in which ice crystals can form in a cloud.

The Doppler radar has the capacity to measure the speed at which falling rain is moving horizontally toward or away from the radar antenna.Falling rain moves with the wind.Consequently,Doppler radar allows scientists to peer into a tornado-generating thunderstorm and observe its wind.