Seeing global windsFeb 28, 2014
The “earth” website by Cameron Beccario is an intriguing way to get a feel for global wind circulation. This view from “earth” shows winds high in the atmosphere.
You’ve heard of working for peanuts, but how about for pickled herring? Software developer Cameron Beccario, who devised a fascinating and informative global weather visualization website called “earth” (earth.nullschool.net), has been offered pickled herring and salmon from an Alaskan commercial fisherman, a confessed big fan of “earth.” Beccario, an American software developer living in Tokyo, has received plenty of positive comments on his site. Earth isn’t a weather forecast site like Weather.com, for example, but more a way to help people visualize global weather patterns.
If you go to the site you’ll see why weather fans from pilots to fishermen to voyagers have embraced “earth.” The site provides a mesmerizing view of the globe with colorful wind patterns playing out across its surface.
The inspiration for “earth” was hint.fm/wind/, a site that displayed wind speeds across the U.S. using gridded binary (GRIB) data. Beccario, who was between jobs, liked hint.fm/wind and decided to set up his own version that would show winds and other weather parameters across the globe. He thought it would be an interesting challenge and a good demonstration of his software development skills.
“My previous job was working on stuff deep in the data center,” Beccario said. “I never got close to a Web browser.” For “earth” Beccario wrote in HTML and Java Script and was looking to build an entirely Web-based app. Having not worked with these tools before, he needed to learn about Java Script tools for interpreting GRIB data and displaying it. He found a site called GitHub, which is a community site for people to share source code. “I got really lucky and found some GRIB decoders there.”
He also picked up a software tool called D3 that does geographic rendering of global map projections. D3 has a library of cartographic projections in addition to the basic globe. Beccario also had to learn about weather and the ways that the U.S. National Weather Service provides data for public use. He was pleasantly surprised when he started to delve into weather enthusiast sites. “I was blown away by the size of the weather enthusiast community online,” Beccario said. “A lot of people who want to talk about weather all the time.” The feedback Beccario has received has come from the general public, from pilots and, of course, from mariners. “My site sits in the nexus of all those interests,” Beccario said. “There’s been lots of good feedback, really happy to see how it resonates with people.”
The GRIB data used on the site is produced at the National Weather Service’s Environmental Modeling Center (EMC). Every six hours supercomputers at EMC take data from surface observations, radiosondes, aircraft, ships at sea, and from weather satellites, and crunch it using sophisticated algorithms that attempt to simulate the complexities of the atmosphere. The result (called Global Forecast System or GFS) is a forecast for every three hours for up to 16 days ahead (typically the accuracy falls off with time so the forecasts are generally only used for out to six days). Not only does the GFS forecast extend forward for multiple days, it is also calculated for multiple zones of atmospheric pressure (pressure roughly equates with altitude above the Earth’s surface). The result of this multi-day, multi-level approach is a large body of forecast data. For Beccario’s “earth” site, he only uses eight levels of the forecast data set: surface, 1,000 hectopascals (hectopascals are the same as millibars), 850 hPa, 700 hPa, 500 hPa, 250 hPa, 70 hPa and 10 hPa. Users can view the forecast activity at each of these atmospheric levels by clicking on the “earth” text in the lower left of the screen.
Other ways to change the data on view include toggling between local time and UTC, moving forward and back through the six-day forecast, changing the weather data overlay (wind, temperature, total precipitable water, total cloud water and mean sea level pressure), changing the map projection (Atlantis, azimuthal equidistant, conic equidistant, equirectangular, orthographic, stereographic, waterman butterfly and winkel tripel) and zooming in.
The extensive list of map projections is a good indication that there are many ways to look at the data in “earth.” This was one of the most trying issues for Beccario when he developed the site. GRIB files are georeferenced to specific positions on the globe, but the GRIB data is only for each 1° of latitude. Areas in between required interpolation. Beccario had to take into account how each map projection distorts the data. Getting the data to display correctly almost required a course in cartography. “It was a challenge to fit the GRIB data to the projections,” Beccario said.
Even though the “earth” site uses only eight levels of forecast info from GFS, the data package is a hefty 600 MB which must be downloaded every six hours. And as the site becomes more popular, the bandwidth requirements go up. To keep “earth” loading quickly, Beccario uses a content delivery network provider called CloudFlare, which caches “earth” on multiple servers around the world so it can be quickly downloaded by users.