Last winter, as meteorologists warned of a monster El Niño, researchers at the Nature Conservancy in California prepared to mobilize. El Niño promised to bring in king tides that would raise the sea level by as much as one foot above normal during high tide, causing flooding along the coastline that researchers could study as a preview of climate change-induced sea level rise. But when a king tide arrives, it floods lots of pockets along the coastline at once. So they decided to try a new, distributed surveillance strategy: commercial drones, co-opted from a gung-ho statewide network of citizen scientists.