Scientists have used space lasers to track the migration of ocean creatures.
The power of space lasers
Under the darkness, every night, numerous sea creatures swim from the depths of the ocean to feed. This vast animal migration, which is a historic phenomenon on the planet, and one of the critical parts of the climate system, has been witnessed for the first time. Thanks to the unexpected use of space lasers.
Researchers discovered this migration pattern through the Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) satellite. It is a joint venture between NASA and a French space agency, which was launched in 2006.
Chris Hostetler, a scientist at Langley Research Center in NASA Hampton, Virginia stated, "This is the latest study to demonstrate something that surprised many people as well: the lidars have the sense to provide useful ocean measurements from space." He also added, "I am guessing we are just scratching the ocean science's surface that can be accomplished with lidar."
The study looks at a phenomenon called Dial Vertical Migration (DVM) in which tiny sea creatures swim at the ocean depth to feed near the surface, then returns just before sunrise. Scientists notice this regular movement around the globe as the largest migration of animals took place on Earth in a huge amount.
Mike Behrenfeld, a lead for the study and a senior research scientist at Oregon University in Corvallis, Oregon said, "What the space lidar allowed us to do is to sample these animals migrating on a scale every 16 days for 10 years." Also, he said, "We never had anywhere near that kind of global coverage to allow us to take a look at that behavior and disturbance of these migrating animals."
The researchers also recognized long-term changes in the populations of animal migration, most likely influenced by climate variations. During the study period, which is from 2008 to 2017, CALIPSO data showed an increase in migrating animals in the subtropical waters of the North and South Pacific, North Atlantic, and South India oceans.
Taking things to the next level
Moving forward, Behrenfeld expects that this will be just another proof-of-concept for more detailed work. He said, "The instrument we used for this project was not really designed or prioritized for oceans, to be honest. We just made something that was already present to showcase the idea."
For example, the current and present technology used is able to probe only the top 22 meters of the ocean. But while it is good for capturing clouds at the right resolution, it is not enough for the kind of high-quality data that Behrenfeld would like to reach.
He said, "You can make laser measurements that have centimeter vertical resolution," he also added, "What would really be efficient for the ocean would be something that can give us data on the vertical structure of plankton every few meters. That would be great."
ALSO READ: Scientists tracked billions of migrating ocean animals using a giant space laser
