Thanks, Colin. I'm familiar with Wilson Bentley's snowflake photographs. I am trying to figure out where they are for sale now in New York. That article doesn't mention where that I could see. Here's a link to the Jericho Historical Society's Bentley exhibit that is in Vermont: Snowflake Bentley Museum
The snowflake schema is represented by centralized fact tables which are connected to multiple dimensions.The dirt particles make the snowflake heavier, and can cause cracks and breaks in the crystal and make it easier to melt. Snowflake formation is a dynamic process.Snowfall amount and its related liquid equivalent precipitation amount are determined using a variety of different rain gauges.