What Is Watermelon Snow and Why Is It Pink?

TL;DR

Watermelon snow is pink due to a type of green algae called Chlamydomonas nivalis, which has a protective red outer layer that shields it from solar radiation. Found in elevated snowy regions worldwide, this algae thrives in spring as the snow melts, but it's generally advised against eating it due to potential digestive issues.

Transcript

If it snows where you live, you’ve probably been told not to eat the yellow snow, and for good reason. But what about pink snow that smells vaguely of watermelon, aka watermelon snow? It’s not pink because it’s contaminated with blood or anything — watermelon snow has algae in it. But you probably still wouldn’t want to eat it. People have been try... Read More

Key Insights

• 😪 Watermelon snow gets its color from a red outer layer of algae called Chlamydomonas nivalis, which protects it from solar radiation.
• 🎚️ This type of green algae can withstand cold temperatures, high levels of solar radiation, and low nutrient levels.
• 🏂 Watermelon snow is found in high-altitude regions with less atmosphere and reflective snow, making it prone to photoinhibition.
• 😪 The algae's cells have flagella to swim up to the snow's surface, shed them, and form thick walls with the red pigment.
• 🏂 Watermelon snow supports the growth of other organisms, such as protozoa and microscopic animals.
• 🏂 Sun cups, indentations in the snow, intensify the color and melting of watermelon snow due to a positive feedback loop of heat absorption.

Questions & Answers

Q: Why is pink snow called watermelon snow?

Pink snow is sometimes called watermelon snow because it has a sweet smell similar to watermelon. The pink color comes from the red outer layer of the algae that give it a watermelon-like appearance.

Q: How does watermelon snow protect the algae from solar radiation?

Watermelon snow has a red outer layer called astaxanthin, which acts as a sunscreen for the algae. It absorbs the excess solar radiation that could damage the algae's cells and turns the snow pink in the process.

Q: Where can watermelon snow be found?

Watermelon snow, or Chlamydomonas nivalis, can be found in snowy, elevated regions all over the world. It is found in places like California's Sierra Nevada mountain range, Australia, and Europe.

Q: Is watermelon snow safe to eat?

While there have been reports of eating watermelon snow causing diarrhea, a scientific study with seven participants did not show any digestive issues. However, it is still advisable to eat it at your own risk.

Summary & Key Takeaways

• Pink snow, also known as watermelon snow, gets its color from a type of green algae called Chlamydomonas nivalis.

• The algae have a red outer layer that protects them from solar radiation and turns the snow pink.

• Watermelon snow is found in snowy, elevated regions and supports the growth of other microscopic organisms.