From Old Ship Logs, A Digital Project Charts Future Weather

May they whose Lot this Log to keep
Be worthy of the Task complete
And never leave a sentence out
Which should occur the voyage about

—Inscription on the cover of a 19th century ship's logbook

The morning of April 19, 1875, dawned cool and foggy in San Francisco Harbor. Aboard the United States Coast and Geodetic Survey Ship Yukon, Assistant Commanding Officer Gershom Bradford stepped onto the deck. He watched as the men set up the rigging and filled large tanks with fresh water in preparation for the schooner's upcoming voyage. He was eager to be underway. As was I, having recently joined the crew.

Well, sort of. As Bradford gazed into the mist 138 years ago, so do I gaze into my laptop's soft glow. The officer's script in the electronic scan of the Yukon's logbook is antiquely florid, but I do my best to transcribe his observations. Once finished, I click "Save." One day down, thousands to go.

This is Old Weather, a citizen-science project run in part by the National Oceanic and Atmospheric Administration and the National Archives and Records Administration, as well as a host of museums, universities and historical societies. It conscripts members of the willing public, like me, to sift through logs from 19th and 20th century U.S. Arctic surveys, and transfer ship locations, weather observations, air and water temperature, and barometric pressure data into spreadsheets more suitable for statistical analysis. Ultimately, the data will help scientists better understand how the climate has varied in the past, and improve projections of change in the future.

I feel a thrill at the thought of joining the Yukon on this adventurous and newly virtuous mission. I chose her because she was one of the first American vessels to explore the western Aleutian Islands—a place I've always wanted to see. But when we ship out, we don't head for Alaska. Instead, we sail up the coast to Eureka, where we spend a few weeks measuring the depth of the seafloor by day, returning to the harbor at night.

Sometimes we anchor off Humboldt Point, which I'm sure is very pretty.

Still, it's not exactly the derring-do I was hoping for.

Old Weather was originally a British project. In 2010, climatologists with the U.K. Met Office (roughly the British equivalent of the National Weather Service) were looking for ways to test how well their climate models could recreate known conditions. The better the models performed on the past, the more trustworthy their predictions of the future. But almost all available historical data came from land-based weather stations, starting in the 1920s. What was needed was older data, marine data, and there happened to be a group of people known for their meticulous weather records: sailors.

The first Old Weather ships were from the Royal Navy during World War I. Even in the heat of battle, sailors had taken time to note whether it was raining. But those logbooks were scattered in archives and libraries. Simply scanning and transcribing them could take years, and no one had the time, the money, or, frankly, the inclination. Why not subcontract the drudgery to volunteers?

Old Weather was in its early stages when Kevin Wood, a historical climatologist with the Seattle-based NOAA-University of Washington Joint Institute for the Study of the Atmosphere and Ocean, met one of the project's leaders at a talk in Baltimore. The fellow worried he would soon run out of ships; volunteers had blitzed through the logs of 238 in just a few months.

Wood felt the click of a good idea: What if they expanded the project to include Arctic surveys from the 1800s and 1900s, when the U.S. government sent ship after ship to Alaska and beyond? The region was a sort of historical climatic frontier since there weren't many weather stations at those high latitudes until recently. He returned to Seattle and spent the next year and a half convincing the National Archives to photograph logbook pages. Last October, the first 14 ships were put online; now, the imaging team has photographed nearly 275,000 pages. Close to 25 million new data points are now available, helping establish a climatic baseline for the Arctic against which to compare current changes.

Old Weather scientists can use the data to reconstruct the weather across the globe, from the surface to an altitude of 30,000 feet, for the past 200 years. They can look at how weather patterns in one part of the world related to events elsewhere—examining, for example, what atmospheric conditions contributed to the formation and trajectory of the Galveston hurricane of 1900.

The precision is intoxicating. "With something like an ice core, you're just looking at an annual layer," Wood says. But with Old Weather, you can find out what the weather was doing at a specific time and place in history. Want to know what the weather was like at four in the morning on May 19, 1873 at North 54 degrees 31", West 165 degrees 351"? Now you can!

The Yukon meanders off the California coast for a few weeks, diligently sounding. As the days pass, high on virtue but short on adventure, I'm tempted to desert. Maybe I could go to the U.S.S. Concord, a gunboat sweeping through the South Seas on its way to guard fur seal colonies in Alaska. But then the log leaps to April 1873. Our quest: a survey of the Unalaska Territory.

The data now take on the giddy momentum of actual transit. As I enter the Yukon's coordinates into the set fields of the dialogue box provided on the Old Weather website, a little orange ship icon scoots across the cornflower blue sea on a small map beside the log pages. We tack north and west, out across the Pacific. Though the seas are rough and the skies squally, we make good time. At 11am on May 16, we see an island some 45 miles distant. We skirt along it and other islands for a few days before anchoring at Unalaska Island. It is the first land we have set foot on in weeks.

If the crew feels excitement or relief, there is no note of it in the log; they are too busy furling the main- and foresails, or salting codfish. I have to content myself with my own awe, distanced as I am in time and space. I do an image search for Unalaska, and up pops a Google-collage of rugged mountains set against miles of tundra and cold black water. The tableau is breathtaking, not that I can do anything but look. It's like peering through a porthole.

But my remove is also fitting; scientists often have to make do with the proximal and indirect when seeking information on remote regions like the Arctic. When whalers, for instance, would return from their years-long voyages to places no one else dared visit in the 19th century, scientists would eagerly troll the logbooks for notes about geography or animal occurrence to help expand their understanding of the world.

Old Weather continues that tradition of resourcefulness, and Wood has his sights set on those whaling logs for another phase of the project. (More than any other type of merchant ship, whalers ranged far and wide across the oceans, which means even greater geographical coverage.) He says that some participants have found their own layers of meaning in the data, and puts me in touch with Stuart Franklin, one of Old Weather's most prolific enterers. An Englishman, Franklin has lived in Australia for the past 40 years. He worked for the British Merchant Navy, first as a fitter and then a machinist; later, he taught at a technical college. He's retired now, and estimates that he works on Old Weather for about 30 hours each week, minus the two days that he volunteers at a steam engine museum.

Franklin isn't only interested in the voyages, but also in what the log comments reveal about the crew. On the Concord, for which he has entered hundreds of pages, Franklin started keeping a list—who deserts, who is commended, who is jailed, who is killed when a steam pipe explodes. He does this out of a sense of responsibility I understand. We can pretend to higher scientific purpose, overseeing whole voyages without mucking about the daily tasks, but as anonymous volunteers ourselves, our real affinity is with the anonymous sailors who manned these ships. One day, when the results of Old Weather are published, perhaps our own toils will be listed somewhere, but more likely no one will notice. On the ships' front pages, where our usernames are listed next to how many records we've completed, there is the same dynamic as on ships themselves: People come, people go, the data march on.

I think back to a page from the Yukon's 1875 voyage. On April 30, a seaman named J.H. Arthington disappeared from a weather station, taking a boat with him. Who was he? Had he stolen the boat and tried to escape? Was he attacked? Was it an accident? About a month later, there was a small note: "The body of J. H. Arthington was found by Indians on the Beach and brought to Eureka." Nothing more. I clicked "Save" and the page turned, and it was the next day, the Yukon once again sailing for Trinidad to survey the seafloor.

This story first appeared in High Country News.