What Can Watermelon Snow Teach Us About Climate Change?

Western Washington University's Dr. Robin Kodner is leading a fascinating citizen-science effort to better understand and document climate change through studying watermelon snow. Read on to see how you can get involved!
Steve Smith Steve Smith
Adult Education Manager
April 29, 2018

The Mountaineers is excited to partner with Dr. Kodner and her students from Western Washington University on a citizen science project this summer related to snow algae. In the past our members have helped monitor invasive weeds and pika populations. This year you have a chance to take your alpine adventures to the next level and collect samples of summer watermelon snow algal blooms. These samples will support studies related to climate change and algal evolutionary biology.

The Mountaineers and Dr. Kodner want to make this easy for our alpine adventurers to participate, so we'll have a supply pick up box at the Seattle Program Center and pre-stamped envelopes for return.You'll be able to pick up kits starting at the end of May, although due to the snowfall we've received this spring the blooms may not show up until the end of June. Learn more about the project and field collection through our Q&A with Dr. Kodner!

Five Questions for Dr. Kodner

What are you hoping to learn through “The Living Snow Project”, and why does it matter? 

The Living Snow Project’s main goal is to characterize snow algae communities (snow microbiomes) and their response to climate change.  We want to understand where snow algae bloom, how they disperse around the landscape, and how their communities evolve over time. We need to collect lots (hundreds) of samples across from as many locations as possible over time to document the biodiversity and abundance across seasons and from year to year.

What are some key discoveries (or surprises) in your watermelon snow research so far?

So far, we have processed samples from 2013-2017. It looks like we have some new “species” of snow algae in the PNW – the strains we see here are genetically distinct from samples sequenced from Europe, Greenland, Japan, and Antarctica. We also see that each community (the algae + bacteria, fungi, and other amoeba-like things) in a region can different. For example, we have a number of samples from different elevations collected around Glacier Peak, and they are all different.  With more samples, we will be able to understand how random this variability is. Our goal this year is to get 500 samples with the help of volunteers!

How do you see Mountaineers members supporting you on this project?    

How do you see Mountaineers members supporting you on this project?    

The Mountaineers have such a strong history of getting folks into the mountains and building a community who value education and stewardship.So, I see this as a wonderful opportunity to both educate many people about snow microbiomes and how important they are on a landscape scale, and also engage them in the process of doing science. My goals for studying snow microbe communities are ambitious and I cannot do this kind of research without the help of our alpine community. Ultimately, I want participants to feel like we are all part of a big team working to study our precious alpine snow and glaciers. 

What exactly are you asking us to do? 

Volunteers who sign up will get a collection kit. Each kit has two sample collection tubes, two gloves and some plastic sealing film. We want people to bring the kits out with them on their adventures, and grab a sample of pink snow if they see it. The tubes have a DNA preservative in it (non-toxic) and people can scoop pink snow into the tube with the cap, while wearing a glove. We typically want the brightest pink snow, so we ask people to look around and sample a spot that looks bright and clean. If there is lots of snow algae where the collector is hiking or climbing, we want them to just pick a convenient (or scenic) spot. We are also using a phone app this year where people can upload pictures of the snow patch they sample along with a few other details and observations about the collection location. In addition, we would love to have people snap photos of the people doing the collecting and post them to social media use the hash tag #livingsnow and/or a hash tag of the watermelon and the snowflake icons (we show this on our website and Instagram account @kodnerlab) and tag @kodnerlab. This is a fun way for all everyone to see the cool places people are sampling. I think it will be fun to have a big regional community of people collecting.

Will the snow sample kits make our packs super heavy, or pose massive logistical challenges in getting you the data you need? 

No! Kits are small and light. As a climber myself - I know how important it is to keep them small, light, and easy to use. Just ask my climbing partners how many times I have asked them to wait for me on a glacier at 5am while I'm scooping snow into a tube! To make them happy I have figured out how to make the process easy enough it only takes 5 minutes with two sets of hands and a few minutes more with only one set of hands.

I recommend if you have a group, one person use the Epicollect app to take a photo and record GPS coordinates while the other scoops the pink snow into the tube. Then the person with the phone can easily share out the GPS coordinates for the scooper to also write on the tube label directly (the redundancy is helpful). If you are by yourself, you just need to scoop, then use the phone to get/record photos and coordinates. You need to wear a glove on the hand you scoop with to prevent contamination, and it is difficult to use your phone with a glove on. If you do not have a smart phone, you can just collect the sample without recording it on the app. We made a video that is on YouTube (link on our website) that shows you how to scoop snow using the lid of the cap.  

Bonus questions

Is it true that eating watermelon snow will make you sick? 

There is lore that watermelon snow will make you sick. I personally haven’t eaten any – but I know too much about microbes to want to eat it! My climbing partners tease me because I am the only one who doesn’t like drinking straight out of a glacial stream. I always say, “There are so many flagellates in there!” and they say, “yummmmm, flagella!”.  Back to the question – the algae themselves are not toxic and shouldn’t make you sick. There are many other fungi, bacteria, amoebas, and other tiny creatures that could give you some intestinal issues. A group of scientists at the University of Nevada Medical School published a study in 1997 comparing stool samples of people who ate pink snow, and those who ate white snow, and they did not find any differences.

Why does watermelon snow smell like …. Melon? 

I don't think anyone knows actually! There are not any published studies that I now of that have tried to characterize the compounds that smell like watermelon. Our observations suggest that it’s more common in slushy snow because we have smelled it sometimes, and not other times. These algae produce all kids of organic compounds that help them live in cold high light environments, so I bet it has something to do with that.

If watermelon snow is contributing to glacial recession, should we think about getting rid of watermelon snow altogether?

No! Watermelon snow is an integral part of snowy ecosystems. They are the primary producers of their habitat, so if we were to try to eradicate snow algae, all the other critters, like snow worms and snow insects would suffer. I think the better question is to ask are we spreading snow algae around when we walk or ski over  it and then continue up to an algae-free part of a glacier. I think we may be able to learn if that is happening from the data we collect through The Living Snow Project. If we learn that people are an important factor in spreading snow algae, then in the future we may consider cleaning our boots and skis after tromping though pink snow, especially when visiting sensitive glaciers. I wouldn’t worry about it now though. Let’s see what the data show.


Please sign up for your own snow sample kit or check in with the Mountaineers Seattle Program Center to pick up your own kit.

Note: You will mail the kit back to the lab after your sample collection is complete. 

Additional Resources and Information

To learn more, click here

To see a video of snow being collected, click here

To follow on Instagram, click here

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Siana Wong
Siana Wong says:
Wed, May 23, 2018 7:26 AM

Thanks for sharing. Very cool. I just signed up!