CK-12 Foundation
Ck 12: Earth Science: Atmosphere: Pressure, Density, and Temperature Study Guide
[Free Registration/Login may be required to access all resource tools.] Summarizes the key points about atmospheric processes involving air pressure, air density, and temperature. Includes a few questions to check for understanding.
University of Illinois
University of Illinois Urbana Champaign: Observed Dew Point Temperature
Describes what dew point is and how it relates to moisture content of the air. Also explains condensation and relative humidity.
Other
Baranidesign: Air Density Calculator
A calculator that computes air density if altitude, temperature, humidity, and barometric pressure are known.
NASA
Nasa: Gas Properties Definitions
Use this site to learn about basic gas properties including motion, viscosity, and compressibility. Includes links to activities for all ages.
Other
American Meteorological Society: Data Streme Atmosphere
This site provides an extensive amount of weather information. Includes current information, forecasting, and historic weather related events. Weather map symbols and terminology explained.
National Snow and Ice Data Center
National Snow and Ice Data Center: Factors Affecting Arctic Weather and Climate
An introduction to the factors that affect the Arctic's weather and climate: latitude, land/sea distribution, solar radiation, air temperature, air pressure, winds, humidity, clouds, and precipitation.
Wikimedia
Wikipedia: Weather Front
This Wikipedia site tells all about weather fronts, or boundaries between two air masses with differing characteristics. Includes many hyperlinked terms to additional information on related subjects.
Other
National Physical Laboratory: The History of Length Measurement
This resource provides historic information on length measurement in the United Kingdom. Click on the topics on the left toolbar of the article to find out more information.