Snow is an odd character. As she dances effortlessly earthward, she is seen differently by those living in the latitudes that feel her touch. Children see a day off school while their parents see a glitch in the schedule. Skiers dream of sweeping turns down the mountain, artists rush to clutch the beauty in their lens, and city workers see overtime. Scientists see questions to be answered.
One late December afternoon at a government lab in Beltsville, Maryland, Eric Erbe saw it all.
THE DISCOVERY
Eric was testing a newly installed cryo-stage for the lab’s low-temperature scanning electron microscope (LTSEM). Imagine a tall, hollow column of steel atop a large table, surrounded by a tangle of vacuum hoses, colorful cables, and shiny valves—all leading to a now ancient-looking computer with large CRT monitors. Instead of using light like an optical microscope, the smaller bits of our world are revealed by an electron beam scanning a frozen platinum-coated specimen, which then ejects electrons of its own. This stream of electrons is interpreted into black and white images, then captured on film. This new cryo-stage enabled viewing of samples at extremely cold temperatures—near that of liquid nitrogen (-196°C/-321°F). While it sounds like something out of a 1950s sci-fi flick, the year was 1993.
Inspired as he watched the snow falling outside, Eric chilled a specimen holder and storage chamber and went to work. At first, the snow simply bounced off the holder. Even if he managed to catch some snow, how could he get the delicate crystals to survive the next step in preserving this elusive specimen—a plunge into liquid nitrogen? After many failed attempts at snagging a snow crystal, Eric thought to employ a special liquid adhesive made for use in extreme cold. Now, the snow fell gracefully onto the sticky sample holder, settled in, and a few minutes later—swoosh! The cold chemical plunge into liquid nitrogen sealed the deal. He had captured a snow crystal!
And there it was. Kept at subfreezing temperatures, sputtered with platinum, and shot with an electron beam, as the scanning lines made their way across the screen the sample revealed its intricate structure. The broken and fractured symmetry of water’s most magical solid state—crystals of snow. Captured on film, humanity’s perception of snow was forever altered.
From that very first test with snow, Eric knew he was on to something; so did his colleagues at the USDA. This new method of viewing snow eventually came to the attention of another government agency–one who knows more than a little about innovative observations–NASA. The masters of looking at Earth from space saw a unique way to help calibrate and validate satellite observations from afar with on-the-ground imagery.
JOINING FORCES WITH NASA
But why study snow? Beyond knowing when to issue a purple powder alert at ski areas, the study of snow is invaluable as a way to estimate water availability for irrigation; also predict potential flooding from the melt of deep snowpack. In addition, understanding how snow crystals change within snowpack layers helps experts identify and mitigate avalanche risks.
Working with NASA, Eric traveled the country—from Colorado to Minnesota to Alaska—collecting samples from snowpacks and glaciers. Trailing behind his long-legged, graceful and efficient kick-and-glide ski technique one would often find a sled full of collection supplies—a plastic snow shovel, dewars of liquid nitrogen, styrofoam cryo-work chambers, forceps, and custom copper storage devices.
Arriving at a selected site, Eric would join forces with the group to dig a snow pit—sometimes deeper than he was tall. With samples from the pit in-hand, he would pack up, ski back, and ship them home in a special supercooled container. Back at the lab, he would make himself a pour-over cup of coffee and examine the haul. His anticipation never waned, there was always a “hidden gem” to be discovered and shared.
SCIENCE BECOMES ART
The scientific community has gained invaluable insight from the thousands of snow crystals Eric captured: Now, the Snow Gallery offers an opportunity for the general public to access these images as fine art. Our careful curation, photo editing and colorization, coupled with high quality, gallery-worthy print productions makes this art truly one of a kind.
-Excerpted from "The Shape of Snow" by Victoria Weeks, published in the Winter 2021 Edition of the Highland Outdoors Magazine.