Sand dunes might look insignificant and like some lifeless objects, but they can be more than that, according to recent research. As researchers from the University of Cambridge unveiled, the dunes can “communicate” with each other as they move.
Utilizing an advanced dune “racetrack,” the team noticed how two resembling dunes approach, then part their ways further and further away. Violent twirls conduct that synergy from the upstream dune, which drags the downstream dune apart. The consequences are incredibly significant for the research of long-term dune movement, which endangers shipping paths, grows desertification, and can bury massive buildings, such as highways.
When a mass of sand is flashed to water flow or wind, it develops a dune pattern and begins circulating downstream with the flow. Dunes, whether on river bottoms, in desserts, or sea grounds, rarely appear in solitude and alternatively occur in bigger groups, creating dazzling shapes dubbed as corridors or dune layers. It’s well-encountered that active dunes move. Their speed is calculated in the inversion of its dimension, meaning that little dunes circulate quicker than bigger ones.
Sand Dunes Can “Communicate”
What’s been a total mystery is how sand dunes within a field can communicate one with another.
“There are different theories on dune interaction: one is that dunes of different sizes will collide, and keep colliding, until they form one giant dune, although this phenomenon has not yet been observed in nature, ” stated Karol Bacik from the University of Cambridge.
Currently, Bacik and her team have displayed results that challenge those statements. Most of the research in simulating the action of dunes is realized numerically. Still, Dr. Nathalie Vriend, leader of the study, developed and built an extraordinary facility that allows analyzing dunes’ long-term actions.
Water-loaded flumes are usually the tools for examining the behavior of dunes in a lab environment. So, the dunes can only be interpreted until they touch the end of the tank. Instead, the team of researchers has developed an oval flume so that the dunes can be examined for as long as they want, as the flume swirls, while high-speed cameras let the team track the flow of each particle in the dunes. Moreover, the dunes began with an identical mass and in the same pattern, too. As the flow started to migrate beyond the two dunes, they started moving.