Solar Radiation Charts

The Solar Radiation Chart collection consists of in situ solar irradiance observations and sun diagrams made at various locations in the United States (including Alaska and Hawaii), the Western Pacific ocean, Antarctica, and Swan Island, Honduras. Charts include long-roll autographic charts, circular charts, and "boomerang" charts (mostly from Antarctica). While there are still some charts received up to present day, most stations discontinued the use of autographic charts in the mid-1980s.