And now, the weather... from 1914

By T.S.

YOU'VE traversed the heavens, exploring distant galaxies. You've scoured the surface of the moon. Now check out the weather during the first world war. Go on, it's for the good of the planet!

Huh? These are all Zooniverse projects that put volunteers to work online, classifying and sorting vast numbers of images so that scientists can use them in their research. The first project, Galaxy Zoo, was launched in 2007. Visitors to its website have categorised millions of images of galaxies, taken by robotic telescopes. This is the type of job that is easy for humans but difficult for computers. It was followed by Moon Zoo, which uses volunteer "citizen scientists" to map and classify craters, mounds and boulder fields on the moon, photographed by an orbiting space probe. (Each image is shown to several people to ensure an accurate classification.)

Both these projects turn a mountain of images into useful data that can be crunched by scientists. Galaxy Zoo led, for example, to the discovery of a new class of compact galaxies called "green peas". Other Zooniverse projects monitor solar storms, hunt for supernovae or examine mergers between galaxies. Scientists get their images classified. Participants enjoy taking part in real scientific research (which has, after all, a long tradition of being done by amateurs). And they compete to see who can classify the most galaxies or craters, providing a further spur to participation.

The latest Zooniverse project, Old Weather, is perhaps the cleverest yet, though. It involves getting volunteers to trawl through the logs of ships, from the period around the first world war, to extract weather observations. Again, this is something that is easy for humans to do but hard for computers (the logs are handwritten). The idea is to plug the gaps in the rather incomplete temperature and pressure records for the period available to climate researchers. Ships, by their very nature, move around at sea, which provides much better coverage than using readings from fixed weather stations on land.

So far, it all sounds just like any other Zooniverse project. But what makes Old Weather even more compelling is that volunteers are assigned to a particular ship, and ships then compete to see who can finish digitising their logs. (HMS Acacia became the first ship to complete the process last week.) Within a ship, moreover, each crew member's rank depends on the number of weather readings they have digitised. You start as a lowly cadet, but as you digitise more readings you get steadily promoted. The idea of turning an otherwise mundane process into a game, to give people more of an incentive to do it, has been a hot trend this year, known as "gameification"; Foursquare, which turns the tedious business of rating restaurants and shops into a huge online game, is perhaps the best example.

You can also look up the historical details of your ship and follow its route on a map. Even if you're not a naval-history buff, this gives the digitising of records a place within a narrative, something that's missing when categorising galaxies or craters. Sometimes the ships are involved in military actions, which are then detailed in the logs. Even mundane reports (a ship's maul lost overboard, in the case of one of the pages I digitised) give a sense of life aboard ship.

Old Weather thus manages to combine crowdsourced citizen science with climate research, naval history, a sense of narrative and vigorous competition between the crews of different virtual ships. That's a pretty impressive combination. Jump aboard!