How Britain's Mapmakers Track Climate Change

Britain's national mapping agency, the Ordnance Survey (OS), has been making detailed maps for 230 years. It started out helping the military defend the country. Today, the OS uses modern tools like drones and huge databases to track how climate change is reshaping the land. From flooding roads to crumbling coastlines, the maps help emergency workers and local governments plan ahead and keep people safe.

Tom Gray is a utilities and transport expert at the OS. He works at the agency's headquarters in Southampton, a port city in southern England. He told the news agency AFP that maps are one of the best ways to see how climate change is affecting the world. 'I would argue there is no clearer way to see the impact of climate change than looking at a traditional map,' he said. He showed aerial photos of Britain on a big screen to prove his point.

The OS keeps a giant collection of location data called the National Geographic Database. It holds more than 600 million features — things like roads, rivers, buildings, and more. The database is updated 30,000 times a day, so it stays current. Gray said it monitors 'almost anything you can think of.' This constant updating makes it one of the most detailed records of Britain's landscape in existence.

Flooding is the biggest climate threat facing Britain, according to Gray. He said 12 percent of the country's major road network sits in the highest flood-risk zone. Twenty percent of the rail network is also at high risk. Emergency workers use OS data to find out exactly where flooding is most likely to happen and how to reach people who are in danger. This helps them respond faster when a crisis strikes.

The OS also uses drone pilots to keep its maps up to date. Helen Jones is one of 21 drone pilots who work for the agency. She flies her drone over areas that have changed — like coastlines that have eroded or new neighborhoods being built — and collects video footage. That footage is then sent back to specialists at headquarters, who use it to update the maps. Every detail, down to 1 centimeter, is recorded.

Jones recalled one case on the Isle of Wight, an island off southern England's coast. Coastal erosion had changed the land there, and the maps needed to be updated fast. After she flew the drone over the site, other agencies like emergency services and local councils could look at the updated map. They used it to figure out where they might need to shut off gas and water lines, and where they might have to evacuate people. It was a clear example of how up-to-date maps can protect lives.

At OS headquarters, specialist Sean Kennedy wears 3D glasses to study the drone footage in detail. Turning one city block of footage into a finished map can take several hours. The maps capture everything from buildings to trash bins to lampposts. This level of detail matters because emergency services need to know exactly where access points to a neighborhood are. During a wildfire or flood, that information could be the difference between life and death.

Jones said she has noticed the effects of climate change in her own work. England and Wales had their driest July on record in 2026, according to the Met Office weather agency. That unusual dry spell meant less rain — which is good for flying drones, but bad for nearly everything else. 'I've not had a summer where we haven't had any kind of rain,' she said. She believes everyone will need to take climate change more seriously in the years ahead.