Understanding Avalanches and the Drone-Based LiDAR Technology Helping Prevent Them

Avalanches

Although backcountry skiing has been around for a very long time, it exploded in popularity in 2020. As you probably remember, the 2020-2021 season was at the heart of COVID-19. Many ski resorts were closed and the open ones had seemingly endless lines. Many people were tired of staying in their homes and were looking for an escape outside and away from people and infection. As such, backcountry skiing became an obvious solution. I mean, what could be better than getting great exercise, fresh snow, and skiing with only people you wanted to ski with? However, this caused a pretty significant problem: a large number of avalanche deaths. In fact, that season there were 37 avalanche deaths in the United States, according to the Colorado Avalanche Information Center (CAIC). This number was the greatest number of avalanche deaths in a year since the CAIC began reporting on it in 2009-2010.

Was the increase in backcountry skiers the sole factor in the rise of avalanche deaths? Not entirely, but it was a contributing factor. A critical aspect of the 2020-2021 ski season was the US's poor snowpack. The season started with little snow, followed by a surge of storms in January, creating conditions ripe for avalanches. Furthermore, avalanches occur most frequently on slopes between 30 and 45 degrees, typical of an average blue run at a Western US ski mountain. So combine a greater number of inexperienced backcountry skiers, many without proper equipment, on high-risk slopes, and the result is more avalanches and deaths.

Although avalanche deaths have decreased post-COVID-19, they still occur annually. With climate change, conditions like those in the 2020-2021 season could become more common, highlighting the need for advanced technology in avalanche prediction and detection.

Predicting Avalanches Using Drone-Based LiDAR Technology

Drone-based LiDAR, short for "Light Detection and Ranging," is a newer technique for avalanche prediction and prevention. LiDAR technology, existing since the 1930s, measures distance to a target object. It emits a pulsed laser beam toward the target, which reflects back to the LiDAR system. The time taken for the light to return, combined with the constant speed of light, allows for accurate distance calculation.

Modern LiDAR technology is far more advanced. Current systems can send thousands of laser pulses per second over a large surface, collecting millions of data points. These, when compiled using computer software, create highly detailed 3-D maps of the target surface. LiDAR has various applications, including land surveying, autonomous vehicles, and aerial inspections. Drone-based LiDAR systems are increasingly popular for scanning remote, hard-to-access areas.

How does drone-based LiDAR aid in avalanche prevention? Consider a scenario in the 2020-2021 ski season: a large avalanche is triggered in a popular backcountry area. Scientists, aiming to understand the conditions leading to the avalanche, first map the area without snow using drone-based LiDAR. As snow accumulates, they continue mapping, incorporating temperature data and RGB color scales to understand the snow's conditions. When a similar avalanche occurs, they can pinpoint the exact conditions that triggered it. In subsequent seasons, monitoring these conditions enables them to issue timely warnings.

Conclusion

LiDAR technology is among several solutions developed for avalanche prediction and prevention. It's crucial for understanding when and where avalanches will occur, especially as climate change leads to more unpredictable snow conditions. Knowledge of conditions that trigger avalanches in high-traffic areas will save lives and improve the skiing experience.