Catching the Rays: New Solar Calculator a Big Hit With Public
Katy Human
NOAA’s Earth System Research Laboratory
September 24, 2009 — The redesigned NOAA Solar Calculator, a Web site that lets users calculate the sun’s precise position, has captured the interest of thousands of Web surfers since its launch in early July.
Screenshot of NOAA’s new Solar Calculator Web site interface. In the example shown, NOAA’s Solar Calculator can help a photographer figure out where to stand (indicated by the red pin) next July Fourth to capture a picture of the Washington Monument framed by the sunset. During sunset, the red line intersects the base of the monument when a viewer is positioned to the southeast. To get a sunrise shot, the photographer would simply move the red pin west or southwest until the green line intersects with the base of the monument, thus indicating a new position from which to shoot. Image credit: NOAA.
Users can use a simple Google map interface to calculate the sun’s angles at any location in the world at any given time — including the times of sunrise and sunset. Simply point to a location on the planet, enter time and date, and voila!
NOAA Earth System Research Laboratory researchers Chris Cornwall, Chris Lehman and Aaron Horiuchi originally created NOAA’s Solar Calculator Web site for their NOAA colleagues in 1999 to help the researchers properly position and install surface solar radiation monitors that are used in the field to gather information about the Earth’s energy budget and climate.
The site quickly gained widespread popularity when it was made public a year later in 2000.
"The e-mails began rolling in," Cornwall said. Many users offered suggestions for improvement as well as thanks, and some of the notes were from unexpected users, such as:
- a green architect who wanted to know the angles of the sun, by season, to help decide how best to build a solar building;
- a small business owner who ran deep-sea fishing trips and wanted to know sunrise and sunset times for trip planning;
- a filmmaker on the West Coast who needed to coordinate a sunset shoot; and
- an ecologist who was studying how albacore tuna behavior changes by time of day and night.
Solar ‘Power’
Taking these suggestions into account, Cornwall redesigned the Solar Calculator this year. He added a feature that allows people to pinpoint their locations on Google’s familiar map interface — something made possible by NOAA’s 2007 licensing of Google Earth and Google Maps API. Soon after launch, visitors streamed in — more than 6,000 during August alone.
“The NOAA Solar Calculator is now one of the most popular Web pages on our site,” said ESRL Webmaster Ann Keane. “It’s surpassed only by our trends in carbon cycle and greenhouse gases and the ever-popular South Pole live camera.”
NOAA researchers still rely on the calculator’s site to set up sensitive monitoring instruments, Cornwall said, but public users have come to depend on it, too.
“Hey you guys, don't you dare take down this page!” wrote an elementary school teacher recently. “You gotta keep it working nicely!”
ESRL’s Chris Cornwall demonstrates how to align radiation instruments with the sun on the roof of the David Skaggs Research Center in Boulder, Colo., at solar noon, when the sun is highest in the sky. Cornwall determined the time of solar noon with NOAA’s Solar Calculator. Photo credit: Will von Dauster, NOAA.