Earth & Space Science
You will take a close look at atmospheric pressure and fronts. Then step into the shoes of a meteorologist and practice what you have learned by predicting weather and hurricanes.
After completing this tutorial, you will be able to complete the following:
What is a psychrometer used for?
~ A psychrometer is used to measure the relative humidity of the atmosphere.
What parts make up a psychrometer, and how does it work?
~ A psychrometer is made of two thermometers, one of which is covered with a tight-fitting jacket of muslin cloth. When using a psychrometer, the cloth is saturated with distilled water and the temperature measured on both thermometers is observed and compared. In a dry atmosphere, water evaporates quickly, which causes a drop in temperature on the wet thermometer.
How do we arrive at a psychrometer measurement?
~ Once the muslin cloth has been saturated, a reading of the two thermometers is taken. The dry thermometer will show a higher temperature than the wet thermometer. This is because evaporation of water from the wet thermometer (which happens more in lower humidities) will cause a drop in temperature. The difference between these temperatures is recorded and, with the use of a special chart, the relative humidity of the atmosphere can be determined.
How is relative humidity related to evaporation from the cloth?
~ The level of humidity determines how much moisture can evaporate from the cloth. The greater the humidity, the less moisture will evaporate.
|Approximate Time||2 Minutes|
|Pre-requisite Concepts||Students should be able to identify and define psychrometers and relative humidity.|
|Course||Earth & Space Science|
|Type of Tutorial||Animation|
|Key Vocabulary||psychrometers, relative humidity,|