Mapping the earth from the sky has been an activity that only governments and corporations could afford to do. It's not anyone who can put a satellite into orbit, maintain it and harvest the high tech imagery.
It turns out, though, that with $100 and a helium balloon, just about anyone can map the earth at better resolution than standard satellite imagery, and Jeff Warren can show you how.
He's the founder of Grassroots Mapping, a group that promotes citizen mapping through the use of DIY kits that include kites, helium balloons and cheap digital cameras.
"The assumption that you could gather your own aerial imagery changes the assumption of what maps could be used for," Warren said in an interview with SolveClimate News.
Over the past year, community activists have created maps to settle land disputes and conduct environmental monitoring, and that's only the beginning of possible applications. On-demand aerial maps could provide vital information for humanitarian or search-and-rescue operations, or during political crises.
Warren launched Grassroots Mapping in January 2010, after working with land-rights activists in Lima, Peru. They needed an inexpensive tool to help them establish legal claims to lands in dispute. Warren developed the methodology with readily available and inexpensive components, and empowered the community, and it inspired Warren to bring the tools to other locations.
Grassroots Mapping has now grown into a loose network of hundreds of people around the world. Some maps turn up spontaneously on the Grassroots Mapping Flickr stream, created by people who simply followed the online instructions.
Warren works closely with about six projects, including land-rights mapping in Lima, mapping the Gulf Coast impacted by the BP oil spill, and environmental monitoring of Brooklyn's Gowanus Canal. The team continues to develop cheap tools for data collection: they've designed low-cost thermal cameras to help with home winterization and prototyped spectroscopy tools that monitor air pollution. In another experiment, they modified digital cameras to take near-infrared photos — an application that could be used for aerial maps of vegetation and ecosystem health.
"We just kind of take it for granted that we have to work with the government datasets," said Warren, explaining the mindset he is trying to change. Many of the best maps are owned by corporations and unavailable to the public. Grassroots Mapping challenges that model by releasing its images into the public domain.
Warren's methodology has another advantage. While satellites fly miles above the earth and cover vast swathes of land, his balloons map the earth from 500 feet in the air and generate images with much higher resolution — up to 100 times more than Google or Yahoo Maps. Satellite maps are often outdated, too; rural areas in particular may not get a fly-over for months at a time.
"When you are making your own maps, you have the power to make it on demand," said Stewart Long, a trained geographer who has participated in several Grassroots Mapping projects. "That's important in a crisis because you can go out and collect data in that moment instead of waiting and paying for a flight to occur."
The BP oil spill is a prime example. Three weeks after the Deepwater Horizon explosion, Warren began collaborating with the Louisiana Bucket Brigade, an organization that supports environmental health in the Gulf region. Traditional aerial photography was restricted by FAA regulations that prevented aircraft from flying lower than 4,000 feet above sensitive areas of the spill. But the rules didn't apply to tethered kites and balloons.
"The media blackout was very concerning to us," said Warren.
The team met cleanup crews and Park Service employees who refused to answer questions about the spill, but ultimately had little trouble gaining access to the beach. The resulting images, taken from about 1,000 feet up, have a startling clarity: one can pick out backyard swimming pools and individual booms, the wake of a boat as it speeds past an oil-stained beach.
Since May, volunteers have created over 40 additional maps of the coast. They hope the images can be used for future litigation or environmental studies (click here for a slideshow of the Gulf Coast mapping project).
Maps as Reliable Datasets
The mapping itself is the easy part. A point-and-shoot camera might cost only $50 on ebay, and helium balloons can be made from trash bags. What's tedious is turning the aerial photos into maps.
There's a big difference between individual snapshots and a finished map, said Warren. Photos that are stitched together become more official and less anecdotal. To that end, he's created a free online program called Cartagen Knitter that allows people to piece photos together. The goal is to create large, detailed maps that are compatible with the ones published by the U.S. Geological Survey (USGS) and other "authorized" sources.
The hunt for legitimacy may be the group's biggest challenge. They want their work to be accepted as reliable datasets.
"We want these maps to be used by ecologists, biologists, social scientists doing research on communities," said Warren. They've started collaborating with several research groups, and Warren hopes it will help the data to gain credibility in academic circles.