From Dune Fiction to Scientific Fact

Last summer, Stephanie McNamara, a geophysics graduate student at CU Boulder, marveled at the breathtaking Great Sand Dunes National Park in Colorado. These majestic dunes, stretching 30 square miles and towering nearly 750 feet, stand as the tallest in North America.

While studying these natural wonders, McNamara quickly learned that grasping the intricate dynamics of sand is easier in theory than in practice. "We experience 'saltating grains'—small sand particles dancing across the dune surface. One moment you feel them against your skin, and the next, they’re swirling into your mouth!" she shared, emphasizing the powerful forces at play.

Dunes: More Than Just a Desert Landscape

Just like the sci-fi desert planet of Arrakis in "Dune," our Earth is dotted with remarkable dunes that occupy over 5% of the planet’s land. They come in myriad shapes, from crescent barchans to star-like formations, and some even 'sing' as the wind interacts with the sand.

But the significance of these dunes goes beyond their aesthetics. With the world facing increasing heat and dryness, understanding the movement of dunes has become critical. Vriend’s research group delves into the shifting sands, aiming to answer a crucial question: Can humans alter the trajectory of these colossal formations?

Facing the Dangers of Desert Expansion

The lessons learned from past events like the Dust Bowl are still relevant today. Vriend expressed urgency in understanding sand movement as deserts continue to expand, consuming farmland, homes, and entire communities.

The Enigmatic Singing Dunes

Vriend, who experienced the mesmerizing sounds of a singing dune in the Mojave Desert, recalls the profound sensation of vibrations coursing through her body as the dune sang. Years of research revealed that this phenomenon stems from small sand avalanches creating vibrations as they cascade down the dune’s face.

Complexities of Sand Dynamics

The science of sand is surprisingly intricate. Vriend explained, "Sand can be solid on one hand, liquid when poured, and a gas when tossed into the air." This duality complicates the tracking of dune movements, as their shifts can vary significantly based on size and wind conditions.

Urgent Research Efforts Around the Globe

For many, the implications of advancing dunes are a matter of survival. In the U.S., communities around Lake Michigan face encroaching sand, while in Mauritania, desert expansion threatens the capital, Nouakchott, with its 1.5 million residents.

Climate change and deforestation are accelerating desertification, potentially impacting over 200 million people worldwide. Researchers like McNamara and Vriend are exploring innovative strategies to manage dune migration.

Pioneering Solutions to Dune Control

Their latest experiments involve unusual techniques, such as planting poles with pool noodle arms in Chile to observe how they impact sand transport. With Vriend reinstalling a massive circular flume in her lab, the inquiry into controlling dune migration is heating up.

Personal Connections to the Research

During a recent trip to Indonesia, McNamara met families devastated by geological disasters and flooding, further solidifying her commitment to researching dune dynamics. "Connecting with people whose lives have changed drastically because of these environmental forces drives my work," she said.

As they continue to investigate the enigmatic world of dunes, McNamara, Vriend, and their team aim to uncover how we might influence, or at least coexist with, these powerful forces of nature.