During a natural disaster like Hurricane Florence, crisis maps can be an invaluable source of information about road and bridge closures and other infrastructure outages. Trouble is, that information doesn’t always trickle down to mobile phones, which is where most people get their maps. (Especially when authorities have trouble keeping up with road closures on their own maps.) CityLab’s Clare Tran explores this question, looking at, for example, how Waze incorporates road closure data from Esri and its volunteers.
When disaster strikes, crowdmapping kicks into high gear. Last Friday, six universities hosted mapathons where volunteers, using satellite imagery, contributed to the map of Puerto Rico and other hurricane-damaged areas on OpenStreetMap. More from one of the universities involved. Here’s the relevant project page on the OSM Wiki.
At NASA’s Earth Observatory, before and after images of Puerto Rico’s nighttime lights illustrate the extent of power outages and infrastructure damage on the island. NASA has also produced a map of likely damaged areas of eastern Puerto Rico, based on before and after radar satellite interferometry and similar to the map they produced for the Mexican earthquake. At ground level, the CrowdRescue Puerto Rico Infrastructure Map displays crowdsourced reports of damage—downed power lines, bridge collapses, floods, mudslides and other incidents.
This crowdsourced map of collapsed and damaged buildings in Mexico City (in Spanish) appeared shortly after the 7.1-magnitude earthquake hit central Mexico on 19 September [via]. NASA also produced a map, based on radar data from the ESA’s Copernicus satellites that compared the state of the region before and after the quake. Interestingly, the data was validated against the crowdsourced map.
The New York Times produced maps showing the pattern of damage in Mexico City and the extent and severity of earthquake shaking (the Times graphics department’s version of the quake’s Shake Map, I suppose) as well as how Mexico City’s geology—it was built on the drained basin of Lake Texcoco—made the impact of the quake much worse.
This is a list of maps related to the flooding in southern Alberta (Calgary, Canmore, Bragg Creek, High River, Okotoks, etc.). This list will be added to as needed. Feel free to contribute additional links in the comments.
- Evacuation zone maps from the City of Calgary, in PDF format.
- For a wider view, an interactive map of Calgary evacuation zones from CBC News.
- A map of flooding zones across Alberta.
- A flood report map from the Calgary Herald, using reader submissions.
- A mobile site for crowdmapping flood reports (thanks, Matt).
Update, 10:15 PM:
Update, June 22 at 8:25 AM:
- Google’s Alberta Flooding Crisis Map.