Professor Jo Nield and her colleagues from the University of Southampton have carried out a pioneering study. Through their research, they have channeled the spirit of Jackie Chan to explore the mysterious mini dune phenomenon, known scientifically as proto-dunes. Conducted in Namibia, the research utilized advanced terrestrial laser scanning equipment to observe these small formations, which can rise up to six centimeters in height. The study’s results indicate that proto-dunes are capable of developing and eroding away in a rapid amount of time. Their dynamic behavior demonstrates their adaptability in both dry and wet conditions.
Scientists investigated these wee dunes in several different places. Besides focusing on the dry ecosystems found in Namibia, they studied the more humid habitats of Colorado and Norfolk. The first task undertaken by the research team was to determine the conditions in which proto-dunes are born, thrive, and die. Here’s how their work is improving our understanding of our own planet’s geological features. In addition, it provides a tremendous new opportunity for studying similar structures on other planetary bodies, such as Mars.
The Nature of Proto-Dunes
So-called mini dunes, or proto-dunes, have unusual and rare properties. They’re capable of developing at an alarming rate, growing from a blank template to six centimeters in length in just a half hour, as seen by researchers. Just as interesting is how they can go away almost as fast. This quick change leaves mini dunes elusive to study in-depth. Their diminutive size and rapid locomotion require advanced and streamlined observational methods and experimental approaches.
Professor Nield explained, “These are the kind of smaller scale sand bedforms that people would see forming before their eyes on the beach before the wind stops or the waves wash them away.” This comparison evokes the delicate transitory allure of proto-dunes and emphasizes their occurrence across a multitude of landscapes.
The research adds that proto-dunes are not limited to Earth. The research team found that sand exhibits counterintuitive and surprising behavior on non-stick surfaces. Rather than simply bounce along the ground, it’s capable of leaping nearly a meter into the air! This behavior makes it all the more complicated to study mini dunes and understand how they form and what their formative processes are.
Insights from Computer Modeling
A key part of this research was creating a computer model that allowed scientists to duplicate and observe the dynamics behind proto-dune formation. Co-authors from Paris contributed to this effort, creating a model that accurately reproduces what researchers observe in their field studies.
“The model can replicate almost perfectly what we see in our field data. Interestingly, we see similar patterns in arid areas with gravel and coastal areas where there’s moisture.” – Prof Philippe Claudin
The model provides an opportunity for researchers to create varying environmental conditions. It opens new windows into how environmental factors such as wind and sand availability affect dune behavior. According to Professor Nield, “Using the model, we can see that if there are really strong winds, the dunes will get bigger and bigger, whereas if there is not much sand coming in, the proto-dune will erode and disappear.”
Knowing where and how these mini dunes find themselves interacting with the things around them is of course key. Their impact on wind patterns is enormous. Once these bumps start to grow, the change in airflow patterns that their presence creates sends them more sand and helps them keep growing even larger.
Broader Implications and Future Research
The impacts of this study reach far beyond our home planet. Professor Nield expressed excitement about the potential applications of their findings: “We are really excited to see how what we’ve learned on Earth could be applied to Mars and to understand similarities and differences between proto-dunes on the two planets.”
Scientists study how these mini dunes function under different conditions. This research aids them in making comparisons between Earth’s diverse environments and those on Mars, where analogous geological processes could occur. This new work opens up a whole new frontier for exploring planetary geology. It makes explicit how landscapes change in different places.