Chapter 16 Understanding Weather: “Back to Basics” A Unit Review!

Chap 16, Sect 1 (Water in the Air) Objectives: 1.Explain how water moves through the water cycle (this is review and is important because this is what can build or give power to storms). 2.Understand the role of humidity in the air.

Tech Terms: 1.humidity – the amount of water vapor in the air. 2.relative humidity – the amount of water vapor in the air compared to the max amount the air can hold at a given temperature. WHAT DOES Humidity HAVE TO DO WITH HOW WEATHER AND CLIMATE ARE PRODUCED ON EARTH?

 When air has MORE energy, MORE water vapor can fit within the gas particles (High energy air = High relative humidity) High energy air is LOW pressure This builds storms!  When air has LESS energy, LESS water vapor can fit within the gas particles (Low energy air = Low relative humidity) Low energy air is HIGH pressure – “HIGH AND DRY”

3.condensation – the process of a gas becoming a liquid (air must have a relative humidity of 100% and air must become cool for this to happen). Water MUST have a surface to condense on! (Examples) 4.precipitation - water, in solid or liquid form, that falls from the air to Earth. (rain, snow, sleet, and hail) (compare droplet sizes)

5.Cumulus clouds – clouds that look like puffy balls of cotton and usually indicate fair weather – until they turn into cumulonimbus.

6.Stratus clouds – clouds that form in flat layers and may produce drizzle, rain, or snow.

7.Cirrus clouds – clouds that are thin and feathery, found at high altitudes, and as they get thicker, indicate a change in weather.