Post on 30-Dec-2015
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DESCRIPTIONRelative Humidity. Is how much moisture a given mass of air is holding compared to how much water that air is capable of holding expressed as a percent. What % full? What would happen to that % if the same water were in a smaller glass?. How to measure humidity -. Sling Psychrometer. - PowerPoint PPT Presentation
Relative HumidityIs how much moisture a given mass of air is holding compared to how much water that air is capable of holding expressed as a percent. What % full?
What would happen to that % if the same water were in a smaller glass?
How to measure humidity -Remember - evaporation cools things (sweat, misters in outdoor cafes, etc.)Evaporation goes faster in dry air.The drier the air - the greater the difference between wet and dry-bulb temperatures.Sling Psychrometer
Hair Hygrometer -Hair changes length depending on humidity - bad hair days!
Cold is airs kryptoniteWarm air can hold more moisture.Cold air holds less moisture.So, cooling air reduces the airs ability to hold moisture, and if that air was holding a lot of moisture, it may drop moisture (condensation).What happens to RH if you warm the air?
Dew point -The temperature that you have to cool air to in order to make the air drop its moisture is the dew point.RH = 100% at DP.Is dew point high or low on a dry day?
If you cool air to its dew point, condensation happens.If you breathe on cold glass, moisture from your breath ____________ on the glass.If you cool air up in the sky to its dew point, water vapor condenses into ___________.If you cool air near ground level to its dew point, ______ forms.On cool mornings, _____ forms on cool grass.If the dew point is below freezing (32f or 0c) and the air gets that cold , _______ would form on grass instead of dew.
Why do clouds have flat bottoms?