Old Weather Data Aids Climate Science -- One Ship at a Time
At midnight on August 31, 1917, the British Navy ship HMS Bacchante encountered a frightful beast of a storm as it patrolled the waters off Dakar, Senegal. Two years earlier, it had survived a key World War I battle in the Dardanelles, providing support to the French, British, and Australian troops at the battle of Gallipoli in Turkey. But this storm came with a different kind of assault. Squalls, rain, thunder, and lightening battered the ship, whose 760 crewmembers surely didn’t get any sleep.
That’s some of the worst weather recorded so far by volunteers at Old Weather, a citizen science project recently launched by climate scientists at Oxford University. Created by the same group that introduced the wildly successful Galaxy Zoo, a 2007 initiative that used online volunteers to classify 1.25 million galaxies, Old Weather has already enlisted some 6,000 volunteers to transcribe the weather data from 238 World War I-era British Navy ships, page by digitized page. The data, about 60 percent complete, will eventually be incorporated into a much larger database of weather records dating back to the 18th century, and will ultimately be fed into climate prediction models in hopes of making them more accurate.
The professional scientists who organized Old Weather are especially interested in outliers -- unusually large storms like the one that slammed the Bacchante nearly a century ago. For though scientists know that major storms are getting more common and intense worldwide, our ability to predict them remains limited. Knowing more about when and where they’ve occurred in the past, and under what conditions, can be a big help, says Philip Brohan, a climate scientist at the U.K.’s Met Hadley Office, one of the world’s leading climate change research centers.
British Naval ships provide an unusually rich trove of data, says Brohan. Not only did they roam the globe, but several times a day, the lieutenant on watch would record the weather in a logbook -- including details on everything from air and sea temperature, wind direction, and wind speed to barometric pressure and precipitation. That type of detailed hourly information (common with today’s 24-hour forecasting services, but rare back then) is invaluable for the International Comprehensive Ocean-Atmosphere Data Set (ICOADS), administered by the U.S. government agency in charge of storm forecasting and climate research. "The World War periods -- both I and II -- have very sparse data," says Scott Woodruff, principal investigator at ICOADS. With the Old Weather project, he says, "we really hope to fill those in."
Of course, getting the data out of yellowing logbooks and into powerful computer databases is easier said than done. The pages can be digitized, but you still need human eyes and brains to interpret the often-spidery script and determine what’s relevant among the many details of a ship’s daily life (which tend to include things like reprimands for drunken sailors and loads of chocolate that were lost when washed overboard). Professional scientists and researchers simply don’t have the time and manpower required, which is where the citizen scientists come in.
"The ships become personal to me," says Janet Bein, a retired quality assurance manager from Evanston, Illinois, who serves as a moderator for Old Weather’s busy forum. "You learn what they’re doing, who they’re with, what the captain’s name is, which sailors get in trouble. You really become part of the crew of the ship."
Bein is the "captain" -- the lead logbook transcriber -- of HMS Torch, an unglamorous tender ship that acted as a combination delivery truck, postal worker, and taxi between the Mediterranean and the Black Sea. Patching together some of the Torch’s lost adventures, she says, is what keeps her interested in the arcane weather data she’s charged with collecting. Over a four-day period in April 1919, for example, the Torch towed a Russian destroyer from the Marmara Sea to the Aegean, only to see it sink beneath the waves. A year and a half later, the ship rescued more than 300 White Russian refugees fleeing Red Army-occupied Odessa and transported them to Constantinople. The ship, the logbook notes, had to be thoroughly deloused in port.
Lest the meteorology geeks, retired sailors, and history buffs that Old Weather attracts get too carried away by shipboard life and flub the barometric-pressure readings, each page is transcribed by three different users. The results are checked by software-generated algorithms that look for obvious errors. (A -5 degree temperature logged in Singapore, for example, would send up a red flag.) So far, the volunteers have a 97 percent accuracy rate. In fact, it’s the ships’ original log keepers who appear more prone to error, regularly recording unlikely temperatures and impossible barometric readings -- proof, in case you needed it, that collecting data is easier done sitting at your desk than being tossed about on the open sea.