Editor’s Note: This is the third and final installment in a new series by Ulyana Horodyskyj, who chronicled an earlier expedition to Nepal in a series called, “Climbing Mount Everest,” which can be found by clicking here. Horodyskyj’s work focuses determining how airborne particles such as dust and soot that settle on massive glaciers alter how snow and ice melt, which could affect climate change as well as local water supplies. Other posts in this series, “Return to Nepal”, can be found by clicking here.
After working hard on the glacial lakes of Ngozumpa glacier, it was onwards and upwards to an unexplored glacier near Cho Oyu, the sixth highest peak in the world, to collect albedo (snow reflectivity) data and snow samples to check for pollutants. My teammates, Evan Buckland, a volunteer climber-scientist for the American Climber Science Program, and Karl Rittger, a researcher at the National Snow and Ice Data Center, arrived in high spirits, excited for the journey ahead.
Given the snowfall from Cyclone Hudhud, what should have normally taken only a couple hours to get to our base camp took significantly longer. Powder snow overlaying boulders led to extensive post-holing through the snow, slowing our progress. About mid-day on our approach, the weather turned. We knew it was coming, given high cirrus clouds seen earlier in the day, indicating a weather front.
There’s a saying that you cannot outrun physics. This definitely held true. We saw dark clouds building up behind us, yet we still had hours to go. By the time we reached a decent spot to set up our base camp, it had started snowing and the temperature had dropped significantly. Our primary goal upon arrival, thus, was to set up our tents and dry off. We were so tired from the effort that dinner was just snacks. For me, this was in the form of beef jerky and Snickers bars.
Unfortunately, the trend with the bad weather continued. Though the mornings were very crisp, clear and cold—as evidenced by pretty much everything liquid freezing in camp—by 11 a.m. the clouds would roll in. So, why is this a problem? In my previous post, I mentioned our desire to use albedo data collected from MODIS (Moderate Resolution Imaging Spectroradiometer). The time of day that it passed overhead for our area unfortunately was the same time that the clouds started building over the glacier, significantly diminishing visibility. Other challenges that we encountered in the field included extreme temperature fluctuations, from 1 degree Fahrenheit at night to nearly 100 degrees in during the day on the glacier, which affected battery power, as well as our endurance.
Though we had satellite imagery and ground photos provided by David Breashears, director of the IMAX movie Everest and founder of GlacierWorks, who had done some recon in the area two years prior, we still had to figure out a way to get onto the ice safely. From the imagery, we had determined two approaches that were likely the safest and easiest. Unfortunately, we didn’t have time to scout out both while in the field – it takes a lot of effort and if you get what is called “cliffed out,” meaning you climb up the approach and find that, on the other side is a drop-off with no easy way down, it is a waste of time, energy and resources.
The route we did commit to was pretty straightforward, as it (luckily) turned out. First we had to cross some boulders in a semi-frozen lake. Good balance was key here! A short climb up then led us to a ridge, which we followed for a bit. Then, it was straight down, across a frozen lake and finally a pretty steep and sustained climb, with falling rock and ice, up to the toe of the glacier. This part was the most challenging for all of us. Evan, in the lead, broke the trail, and all of us followed, carrying heavy packs at over 17,000 feet. The fluctuating temperatures made it hard for the body to adjust and our thirst was simply unquenchable due to the very dry air.
Upon reaching the foot of the glacier, we roped up and carefully climbed, probing for any hidden crevasses. Again, due to the cyclone and all the new powder snow, the terrain was very untrustworthy, thereby limiting our ability to go very far on the surface. In addition, given how long the approaches were (sometimes up to 5 hours) even starting early in the morning put us on the ice at the same time the clouds were unfortunately arriving. Leaving too early, before adequate light, was not an option. No other climbers had ever been here, so there was no information on route options once on the ice, and navigating a maze of crevasses is never an easy task, even in the daylight hours.
Despite us not being able to collect useful albedo measurements due to the extensive cloud cover, I did manage to collect snow samples from 17,500 feet down to 15,500 feet to get an altitudinal transect of change. I did this using two techniques. First, I would identify a spot of interest, take a GPS point, and collect a pre-washed glass vial of powder snow on the surface to be later analyzed in the lab using what’s called a soot photometer. Then, using an ice axe, I would probe for a harder layer in the snow.
The powder snow I took to represent the cyclone. Any black carbon found would be what the storm’s snow was able to “sweep” out of the atmosphere as it fell. The harder layer I took to represent the last exposed surface pre-cyclone, which should capture any particulates that fell onto the surface as a result of dry deposition, rather than snowfall.
The other technique involved collecting bags of snow, melting the snow, and then filtering the water to capture particulates for later analysis in the lab. While the first technique—collecting samples in their frozen form—is good at determining mass concentration of black carbon, the second is good for looking at dust versus black carbon.
Now that I’ve completed the hard physical work of field data collection, I will return home and begin the intellectual work of analyzing and interpreting the data, with hopes to complete my PhD dissertation later in the spring. In the Himalayan samples I have measured to date, which includes those from the Khumbu (Everest) region, we are finding that dust dominates the signal. It remains to be learned whether these new samples, and samples from the Annapurna and NarPhu valleys collected from last winter and spring are similar.
Thanks for following along!