Heritage Images/Getty Images toggle caption Heritage Images/Getty Images Shipping workers recorded the tide levels beginning in 1854 at St. George's Dock in Liverpool, England, creating valuable records for future scientists. Heritage Images/Getty Images Off the coast of England, there's a tiny, wind-swept island with the remains of a lifeboat rescue station from the mid-1800s. The workers who once ran the station on Hilbre Island did something that, unbeknownst to them, has become crucial for understanding the future of a hotter climate: They recorded the tides. The data, scrawled in long, handwritten ledgers, is just one example of the tens of thousands of pages of tidal measurements stored in archives around the world. Now, scientists and historians are racing to digitize them in an effort to understand how fast oceans are rising. The aging notebooks establish a historical baseline to compare with today's changing world.