Wilson Bentley, an early 20th century farmer from Jehrico, Vermont, is best remembered as the "Snowflake Man" for his thousands of marvelous snowflake photographs. But Bentley also was a student of the rain. Hi, I'm Dave Thurlow and this is The Weather Notebook.
While photographing snowflakes was his life's work, for six summers Bentley turned his interest to examining and sizing raindrops. His contributions to the science of meteorology are legendary, especially since his exhaustive study, was just a hobby.
Bentley's apparatus for gathering raindrops - a shallow pan of wheat flour - was a marvel of simplicity. While photographing rain splash patterns, Bentley found them to be just about the same size as the falling drops. He divided his raindrop "fossils" into five size categories to determine their size distribution.
He then determined that different kinds of storms produce different size raindrops. Bentley found few rainfall events had uniform drop sizes, but those that did were composed of either all small drops or all large drops. He concluded that the size of drops and flakes tells a lot about the vertical structure of the storm, which before airplanes was a true find. Low clouds he found, produced small drops mostly. The largest drops, around a quarter inch in diameter, fell from miles-high clouds: those of thunderstorms.
Unfortunately, Bentley was so far ahead of his time that he wasnt fully appreciated by contemporary scientists. They didnt take this farmer seriously. It was 40 years before his work was uncovered, work that set up even the current understanding of snowflake, and raindrop, formation.
Thanks to contributing writer Keith Heidorn. Find out more about snowflake Bentley at mountwashington.org