BACKGROUND: NASA Goddard is launching the Global Snowflake Network, a project in which the general public is encouraged to go out and collect and classify falling snowflakes to build up a global database of snowflake data. The goal is to provide an interactive online data resource for the characterization of snowfall and related weather systems. Sites will include homes, schools and other organizations, each of which will have one person dedicated to the identification and Web-based entry of snowflake shapes collected during snowfall events. The serial record will then be archives with serial satellite image records. The public gets to participate in real science while learning more about snow and snowflake formation, as well as helping meteorologists track the weather.
ABOUT SNOWFLAKES: Snow is a form of precipitation. Rising warm air carries water vapor high into the sky, where it cools and condenses into water droplets. Some vapor freezes into tiny ice crystals, which can attract cooled water drops to form snowflakes. As snowflakes fall, they meet warmer air and melt into raindrops, unless temperatures are below freezing close to the ground: then we get snow. A snow crystal is a single crystal of ice. It usually forms the shape of a hexagonal prism, but as the crystals grow, branches sprout from the corners, creating more complex shapes. Conditions such as temperature and humidity in the atmosphere can influence a snowflake's shape.
WEATHER SHAPING: A great deal of information about the atmosphere dynamics and cloud microphysics can be derived from the serial collection and identification of the types of snow crystals during the progress of a snowstorm. The shapes of snowflakes vary over the winter season, with the source of the weather system, and during the progress of any given snowfall. So snowflake shapes are a proxy for conditions in the weather systems responsible for the snowfall. A global snowflake network can therefore be of great value to those who work in winter meteorology. Integrating data entry into a Web-based site will allow tracking of snowstorms as they travel across the globe. Students will be able to see the actual relationships of climate, temperature and other atmospheric features.
The American Meteorological Society and the American Geophysical Union contributed to the information contained in the TV portion of this report.