The world’s highest weather stations have been installed on Mt. Everest and in the Chilean Andes to assess how climate change will impact the water supply of more than one-fifth of the world’s population
The Perpetual Planet initiative: Rolex x National Geographic
As rainfall patterns shift and global temperatures rise, most of the world’s glaciers are thinning and retreating. Nearly two billion people depend on snowpack and glaciers as their main source of fresh drinking water, with agriculture and industry relying on these same reserves too. Snow and ice function as water towers by providing a reliable water supply for people living downstream of these mountainous regions. Getting long-term, continuous data on temperature, wind speed, snowfall and glacial melt from high-altitude regions is challenging. To help bridge this data gap, the Perpetual Planet initiative, organized by the National Geographic Society and funded by Rolex, has supported expeditions to Mt. Everest in the Himalayas and Mt. Tupangato, a dormant volcano in the southern Chilean Andes, to install the world’s highest weather stations. Everest now has the world’s highest weather station while Tupangato is home to the highest in the Southern and Western hemispheres. In 2019, Baker Perry, a professor in the Department of Geography and Planning at Appalachian State University in the U.S., and Tom Matthews, a climate scientist and lecturer at Loughborough University in the UK, served as the meteorology team co-leads for the Everest expedition. Perry co-led the Tupangato expedition in February 2021. Their conversation discusses the need for reliable and robust climate data from high-altitude places like the Himalayas and Andes.
Measuring climate change
Kelsey Nowakowski: Why should we monitor climatic conditions and weather high up in extreme, remote places?
Tom Matthews: Half of the ice in the Himalayas is stored at 5,500 meters and above, and there’s essentially been no monitoring at that height for a long time. We have no idea how quickly it may be melting already, and if we don’t know this, we’re in a poor position to under- stand how it may respond to increasing temperatures. As the temperatures rise, we should expect more snowfall and perhaps more melting where melting is possible. It’s by no means self-evident that the glaciers are going to thin and get smaller at those high altitudes and to fill in the gaps we need to get there and monitor what’s going on now to understand how sensitive those systems – the glaciers and the snow stored up there – are to warming. There are hundreds of millions of people living downstream from these glaciers that provide a reliable water supply year-round. If it gets hot and doesn’t rain in the summer, the glaciers still melt to provide water to communities downstream. They are reliable water sources – what we refer to as water towers. We need to know what’s going on up high, higher than has been measured before, to understand how bad the problem may be in the future and how small those glaciers may get. The more local motivation is to improve the safety of high-altitude mountaineering. Hundreds attempt the peak each year and around a quarter to a fifth of fatalities on Everest have been due to bad weather. It’s not just climbers – it’s also Sherpas who are at risk. Having weather stations up there allows us to have better weather forecasts for climbing safety.
Baker Perry: We haven’t had a good understanding of what it’s like up there. Mountaineers go and they bring back observations from certain times. We’ve had satellites and models do- ing reanalysis, but it’s not the same as having a continuous set of observations, especially of the moisture variables, such as different measures of humidity and solar radiation which is highly dependent on cloud cover. The fact that, for some of our stations on Everest, we have a continuous two-year record of observations is remarkable from a scientific perspective and fills in many voids in our understanding of these locations, and the same thing is happening with Tupungato. Even though it’s so close to the city of Santiago, and the low-elevation sites have been well monitored there, these are novel observations coming in, it’s significant for the immediate people downstream and also globally for our understanding of important parts of our planet that we’ve not understood very well.
Lampoon reporting: Mountain Tupungato expedition
KN Why was Tupungato in the Chilean Andes selected?
BP One reason is that it’s so close to the city of Santiago and those mountains and the upper slope of Tupungato are the critical water tower for the population. Santiago is in the middle of this serious drought so there’s an urgent regional need to understand climate change. Get- ting above 6,500 meters or more is remarkable – we need observations from up there. It’s not as high as Everest, but it’s relevant for water resources.
KN What is the current state of the world’s glaciers overall? Are any of them growing?
TM Worldwide, the vast majority of glaciers are getting smaller. Broadly speaking, they are experiencing accelerating melt rates as temperatures rise, and snowfall cannot keep pace. The result of this imbalance is that glaciers are thinning and retreating.
BP In the Himalayas, it’s well documented that glaciers have retreated substantially. These big valley glaciers have thinned. In the Andes, many small glaciers have disappeared. It’s bleak for Chile and most other mountain regions. In speaking with our colleagues and other people that we’ve worked with on these treks, the concept of diminished water because of retreating glaciers is deeply personal. The older folks have seen the changes with their own eyes and there’s a real sadness that comes with the loss of snow and ice up high that is translated into direct impacts on the availability of water for irrigation, livestock, and domestic use.
TM To give you some context for Everest, around base camp, it’s thinned by about 100 meters since the 1950s. So that means that base camp probably isn’t where it was when Hillary and Norgay first summited Everest – now you’d have to climb 100 meters higher because the glaciers have thinned, and base camp is on the glacier and has lowered now.
KN How are the weather stations constructed and how long can they endure the high-altitude conditions before breaking down?
BP The challenge here is building and engineering a station that is light enough to be carried up in different pieces and then put together, but strong enough to survive the extremes that we see up there and that involves some tradeoffs at times. When Tom and I joined the National Geographic team in the fall of 2018, we got to work with engineers at Campbell Scientific which is the company that designed the station. It was a collaborative process, and we went through many iterations to come up with a design for a tripod that is made from aluminum and light enough to be carried by a single person. There are challenges in installing these systems especially in places like Everest where there’s only a short window once a year to do so.
TM To inform our design standard for the station, we had to estimate how fast the wind can get. We think about 100 meters per second is not out of the question.
Preparing to explore – obstacles and hazards
Kelsey Nowakowski: How do you prepare for the expeditions and for installing the weather stations?
Tom Matthews: I do distance running which is an endurance event. To train for Everest, you need lots of endurance hours, whether it’s running, cycling, or swimming. So, it’s something like ten to fifteen hours a week for two to three months.
Baker Perry: For the four months leading up to the expedition, it’s a lot of volume. By running, you can get the fitness and the volume a little faster than by doing other things. I spent time biking and on trails doing hill repeats, but I needed more volume, so I was training more like fifteen to twenty hours per week. But it takes years to prepare for Everest by going on other expeditions and building that experience with the technical side of things and having a chance for your body to go to altitude to have that confidence that when you get to 25,000 feet that your body will adapt to that.
KN National Geographic expeditions carry an air of prestige and rugged glamor, but explorers are nevertheless exposed to dangerous conditions. What are some of the obstacles you faced on these treks?
TM One of the bits that lingers in my mind for Mt. Everest in particular, is the weakened state of the body in these elements. That normally manifests as the inability to fight off sickness and infection. For me, it’s having a dodgy stomach halfway up Everest. It’s not ever glamorous when you’re looking for a spot to safely go to the toilet. It just feels like surviving when you’re up there. The National Geographic team minimized danger, and made sure we had a world- class Sherpa to help get us up the mountain. There are still hazards like avalanches that you can’t eliminate. Toppling ice blocks are a worry on a portion of the trek. You don’t feel too brave when you hear something lurching and creaking in the dark up ahead.
BP The Khumbu Icefall is challenging. Mentally it’s hard to stay focused at times knowing the objective hazard. On the Lhotse Face it’s nearly impossible to go to the bathroom since it’s so steeply exposed. That, combined with the altitude and the extreme cold and wind, are big factors. In Chile some of the same challenges are there, but it’s not quite as high as Everest. We encountered deeper snow and blizzard conditions that pinned us in our tents. On Everest there’s a fixed line that you can clip into almost the whole time, but in Chile we didn’t have that. When you’re traversing these very steep snow slopes with mixed snow and rock terrain, any slip or fall in a situation like that can easily be fatal.
The support from organizations like National Geographic and Rolex to conduct scientific research
KN Why is it key to have support from organizations and companies like National Geographic and Rolex to conduct this type of scientific research?
TM For what we’re talking about here, which is frontier science – frontier in that it’s asking questions that haven’t been answered yet and in that we’re going to the edge – it’s high risk. Research councils, which are our traditional support method, are interested in the research questions but they are less likely to be willing to take the risk helping us get to these extreme environments because there’s a chance we come back with nothing. National Geographic em- bodies the spirit of exploration. We have actually measured the height of Everest many times now, but we never measured the weather on the upper slopes of Everest, so it’s one of those fundamental gaps in the exploration of our planet.
BP National Geographic has the history and experience for running these frontier science expeditions. There just aren’t many institutions that have the capability to coordinate logistics for this type of endeavor.
Inclusive data that empowers
Kelsey Nowakowski: What are some of the ways these expeditions have engaged local scientists and other local stakeholders in the areas where research is being conducted?
Baker Perry: With the Everest expedition, it was enriching to have so many Nepali colleagues and students from Tribhuvan University in Nepal. National Geographic made sure there were opportunities for Nepali students and researchers to be involved at multiple levels. On the meteorology team, Arbindra Kkadka, a master’s student from Tribhuvan University, helped install the lower station and has been heavily involved in the analysis and publication of results. Another student, Tenzing Chogyal Sherpa, has been involved in our publications too. The Sherpa team that went up above base camp and did most of the heavy lifting for us is a success story. Two of them just returned from a maintenance expedition to the upper stations. Tenzing Gyalzen Sherpa has been instrumental in performing some of the ongoing maintenance of the weather stations, including visits to the higher stations at Camp II, South Col, and Balcony. Inka Koch, a female German snow scientist, also joined the expedition, as did Dawa Yangzum Sherpa, the first female Nepali mountain climber to achieve a certification from the International Federation of Mountain Guides Association. On the Chilean side, the team was led by Gino Casassa and female glaciologist Alejandra Espinoza joined us as well.
Tom Matthews: When all the students and scientists are accounted for on the Everest trip, about half were Nepali. I was impressed by the ambition to make this as international and as inclusive as possible. It wasn’t just a box ticking effort – the skill and tenacity of the young scientists is phenomenal.
What the weather stations have revealed so far
KN How has the data collected from the Everest and Tupungato expeditions been used to aid scientific study? What have the weather stations revealed so far?
TM We are finding evidence that a lot of melt may already be occurring on Everest’s upper slopes – at elevations much higher than we thought melting would be possible. This means the ice stored at these heights – on Everest and elsewhere in the Himalaya – might disappear more quickly than expected as the climate warms, with anywhere that’s already melting more sensitive to increases in temperature. Though air temperatures at these altitudes never really rise above minus ten degrees Celsius, the sunlight is so strong that the snow there can get much warmer than the surrounding air. On some occasions, sunlight coming in at the top of the Earth’s atmosphere is much stronger due to reflections between the snowy surface and the clouds. We’ve also been able to assess the reliability of weather forecasting models that mountaineering teams use. Before, there was no ground truthing data. We’ve been able to show that the forecasts are very good generally up to five days in advance for wind speed. That improves the safety of climbing.
BP We published a paper in November that showed how relevant the Bay of Bengal is for the moisture that ends up falling in the Everest region. We have a paper in the press now with other colleagues that shows that the melt season – when glaciers lose mass – is now extend- ing through portions of the winter. We had a remarkable warm spell in January of this year which resulted in melting of snow and ice even up high. The picture is starting to become a bit clearer as to what’s happening up at these highest elevations. We’ve also been collaborating with the Nepali government’s Department of Hydrology and Meteorology.
TM The world cares about Everest. It’s this iconic location seen as pristine, but it’s the world’s stage for climate change and the more we fill in the gaps for climate data, the more we can push global mitigation in the direction it needs to go. We don’t know how quickly the ice up there will be lost. If our research can help answer how high-altitude glaciers are going to respond to a warming climate, and if that looks like quicker retreat than we thought, it could mean countries try even harder to get to carbon neutral faster. The transition of snow and ice to bare rock is about the most vivid and dramatic you can get in nature. You can see the black face of Everest more frequently as the ice is ablated more quickly. And the locals talk about that. They’ve experienced climate change by the mountains changing from white to black. The more we can shed light on what’s going on up there the more hopeful I am. Some of it is through the storytelling we can do and through our research that can inform policy at the very highest level so countries can revise their commitments to reduce their carbon emissions. It is the biggest issue of our time. It’s incredible that places as localized as the summit of Everest can play a disproportionately large role in illustrating that we need to do something faster.
Baker Perry is a professor in the Department of Geography and Planning at Appalachian State University in North Carolina. He holds a Ph.D. in geography with a focus on climatology from the University of North Carolina and his field-based research interests include alpine precipitation formation, snow and ice, and precipitation-glacier-climate interactions. Perry teaches courses on climate change, atmospheric circulation, snow and ice, mountain geography, and tropical Andean glacier-climate interactions.
Tom Matthews is a climate scientist based at Loughborough University in the U.K. He has broad interests in the societal impacts from climate change but focuses on severe weather events. This drives Matthews to understand the planet’s most extreme climates. From deadly tropical heat waves to severe, cold-weather mountain windstorms, Matthews’s research aims to map the limits of Earth’s climate envelope and chart its course as it is shifted by human-caused climate change.