Geography 103: Weather

Exercise 2C. Hourly weather records from CSUN

There is a link to the CSUN weather station data from the geography home page at http://www.csun.edu/geography/

Current hourly weather records from the CSUN station can be found by following this link, selecting “Weather Station” and then “Current Weather Conditions at CSUN”.

Past weather data is stored in Excel files and can be accessed through this class web page (Weather Data).

In Exercise 2B you plotted the temperature and solar radiation data for June 23, 2002 on the same plot using Excel. In this exercise you will plot the temperature and the relative humidity together, and see how they vary relative to each other throughout the day. After opening up the weather data file in Excel, you should select the plotting icon (“Chart Wizard”) and then choose “Custom Types” followed by “Lines on 2 Axes”. This allows you to use the left axis for temperature and the right axis for humidity with two different scales. You can name one series “Temperature” and the other “Relative Humidity”. Format your chart like the example shown below for March 8, 2002.

Using your graph for June 23, 2002, what can you say about how the relative humidity varies relative to the temperature? Why? When is the relative humidity lowest? Why? When is it highest? Why?