Drones are getting a green makeover as environmentalists and earth scientists put the unmanned vehicles to a variety of eco-friendly jobs, from studying wildlife and polar ice melting to monitoring water for harmful bacteria to reforesting areas that have been overharvested.
At Lamont Doherty Earth Observatory, Chris Zappa is planning his next mission to monitor ice melt in the Arctic, where drones will flit to places that icebreakers and manned aircraft don't dare venture.
“There are places you can’t get to with normal oceanographic capability, so we use drones,” Zappa, an associate research scientist, said from his office at Lamont. “We’re looking at the marginal ice zone, where the ocean meets the edge of the ice, seeing how fast and how slow the melting is occurring.”
Equipped with infrared cameras, the drones collect data on temperature changes and melt water coming off the ice, Zappa said, adding that in future missions drones might drop off micro buoys that will measure the temperature and salinity of the water.
Coming at the problem from a different angle, Woods Hole Oceanographic Institution is monitoring the base of the polar ice with an underwater drone.
A similar drone has been used to observe the deep water habits of great white sharks, which scientists knew very little about until they found a way to follow the big fish around.
By attaching an electronic tag to a shark, Woods Hole scientists were able to program their underwater drone to follow her around, sometimes getting very close. On a recent mission, the drone, dubbed REMUS, came back with some stunning, and completely unexpected data, on how great whites hunt.
The drone, which was equipped with five cameras, showed in some very frightening footage what happened when two young sharks decided that the unmanned vehicle might make a nice snack: chomp chomp.
“What the video shows is unprecedented,” said Amy Kukulya, the operations leader and a principal investigator for the REMUS SharkCam project. “It’s documenting a deep water attack and the vertical speed when sharks make an attack. It shows everything from the perspective of the shark. It’s pretty far out. We realized that in Cape Cod that when a shark saw a kayaker or surfer it had an encounter that was no different from what happened with the REMUS. The sharks were confused. And so they say, hey, let’s take an exploratory bite.”
As it turns out, neither of the sharks that attacked the drone was the one being followed. “Those two major attacks where you just jump out of your seat are two different sharks,” Kukulya said. “First a male and then 25 minutes later a female. It was pretty terrifying. I was definitely surprised. We’re learning a lot.”
Flying drones are also being used by groups trying to protect whales and other big mammals from being killed by hunters. Each year the Sea Shepherd Conservation Society sends out its drones to watch over pilot whales. If the whales get too close to the Faroe Islands, where locals have yearly hunts, small boats are sent out to chase the whales away.
“Once we locate the whales we drive them back out to sea,” said Paul Watson co-founder of Sea Shepherd. “Two years ago from June to September there were 1,300 whales killed. Last year we chased away about a dozen pods. While we were patrolling only 32 were killed.”
For the most part, drones have served as watchers. But in the future, they may be a lot more active.
A company called BioCarbon Engineering has designed a drone to quickly and efficiently plant trees. The goal is to help rebuild global forests that have been decimated by lumbering, mining, agriculture and urban expansion.
Company scientists have developed a prototype drone that uses a tiny cannon to shoot pods containing germinated seeds as well as nutrients and fertilizer to support the tree as it begins to grow. The pod breaks open when it hits the ground, spilling the germinated seeds and nutrients.
Thus far, the method has only been tested in the lab, said Lauren Fletcher, company CEO and co-founder. Fletcher and his team entered their prototype in this year’s UAE Drones for Good competition, which awards $1 million to the winning drone team.
This year’s contest included entries from over 800 teams from 57 nations. There were 19 semi-finalists which were winnowed down to five. The tree-planting drone made it all the way to the finals, but was, in the end beaten by a crash-resistant drone that could be used for search and rescue.
Eventually, Fletcher said, “two operators with our technology could plant at least 36,000 trees a day. That’s a ten times better planting rate than you see with hand planting. The current type of tree planter can plant 1,500 trees a day at a cost of about $3 per tree. With 100 teams of two operators we would be able to do a billion trees a year.”
Fletcher doesn’t see his new device putting traditional tree planters out of business. With both types of planting going on, it still won’t be enough to catch up with the deforestation going on today, he said.
There was, of course, stiff competition, including an entry from an MIT group called the Waterfly, which fields a swarm of drones that test for the presence of deadly cyanobacteria in the water. The Waterfly was one of the 20 semi-finalists.
“Cyanobacteria are common in water all over the world, and under certain conditions they reproduce explosively and produce high quantities of poisonous cyanotoxins,” explained Carlo Ratti, a professor and director of the Senseable City Lab at MIT. “It is very important to monitor them and keep them under control. The swarm monitors water from high and then, when something is detected, individual drones fly down to analyze the water, while the others still fly at high altitude. This makes the swarming system much more efficient.”