Airdate: Jun 08, 2005
Scientist: Ronald (Ron) W. Hoham
Snow Biology - Watermelon Snow
For hundreds of years, reddish snow has mystified hikers in the high country. Now it's secret is revealed.
ambience: River, footsteps walking in snow
Have you ever hiked across an alpine meadow or traversed a steep slope in high mountain ranges and noticed these pinkish patches, or streaks of red, on the snowbanks? Stay tuned. I’m Jim Metzner and this is Pulse of the Planet.
“Watermelon snow is, just as the name indicates is a red colored snow and it is caused by algae.”
Ron Hoham is a professor of Biology at Colgate University in upstate New York.
“They are green algae even though they are red and the red is caused by secondary pigments that are produced that protect the chlorophyll, which you can’t see at that point, from damaging ultraviolet light. Now the watermelon snow in the United States is found in our western states, in the Rocky Mountains and the Sierra Nevadas and Cascades. In the eastern states we don’t have watermelon snow. We have green and orange snows here in the forest regions as we have in the western states as well in the forested regions. But the watermelon snow is found in the open exposures above timberline, at the higher elevations, and it is very prominent in the summer when there are lots of hikers out there and they see it very readily. And there are vast fields of snow colored red to reddish purple from these green algae”
For many years this mysterious pink snow has puzzled mountain climbers, explorers and naturalists alike. Compressing the snow with your boot leaves a very distinct footprint the color of watermelon pulp. The snow even has a fresh watermelon scent.
“I’ve had questions asked of me whether or not you can eat the watermelon snow and recently I did receive a report from the Denver General Hospital about some hiker who had consumed large quantities of watermelon snow and came down with an acute case of diarrhea and de-hydration."
If you'd like to see pictures of Watermelon Snow, please visit our website at pulseplanet.com. Pulse of the Planet is presented by the National Science Foundation. I'm Jim Metzner.