The air around me crackles with diamond-like dust with every breath. It is cold, but clear on this mountainside, in the midst of what is essentially an Arctic desert. The extremely dry, freezing air almost instantly turns the fog of moisture from my mouth and nose into tiny, sparkling crystals of ice.
I am standing just below the peak of Zeppelinfjellet, a 556m (1,824ft) mountain on the Brøggerhalvøya peninsula of Spitsbergen in Svalbard, the Norwegian archipelago in the Arctic Ocean. Beneath me is the town of Ny-Ålesund, a tiny settlement with a population of 45 in the depths of winter and up to 150 at the height of the summer. It is the northernmost permanent settlement in the world, situated around 765 miles (1,231km) from the North Pole.
With the mountain rising on one side, and a fjord on the other, it is a breathtakingly beautiful place. It is perhaps also one of the best places on the planet to take a breath – situated far from major sources of pollution in the almost untouched Arctic environment, the air here is some of the cleanest in the world.
The town's residents are largely scientists who come here precisely for this reason. In 1989, a research station was built on Zeppelinfjellet's flanks at an altitude of 472m (1,548ft) to help researchers monitor atmospheric pollution. More recently the Zeppelin Observatory, as the research station is called, has become a crucial site for measuring greenhouse gas levels that are driving climate change.
But there are also signs that the air quality here may be changing. Occasionally atmospheric currents carry air from Europe and North America to this part of Svalbard, bringing pollution from these regions with it. Not only are researchers seeing levels of certain pollutants increasing, there are signs of new types of pollution being carried on the wind that are worrying scientists.
"The Zeppelin Observatory is located in a remote and pristine environment, far away from major sources of pollution," says Ove Hermansen, senior scientist at the Zeppelin Observatory and the Norwegian Institute for Air Research. "If you can measure it here, you know that it already has a global prevalence. This is a good location to study the changing atmosphere."
Ny-Ålesund is the northernmost civilian settlement in the world (Credit: Roger Goodwin/Alamy)
The research at Ny-Ålesund is a crucial part of an international effort to map humanity's impact on the atmosphere. The measurements they take help to "to detect the base line of pollution and calculate the global trend over time”, explains Hermansen.
Five days a week, an employee from the Norwegian Polar Institute makes an ascent by cable car to the observatory, where they conduct maintenance, take air samples and change filters on the equipment. Due to its remote location and altitude above atmospheric layers that can trap what little pollution is produced locally from the town, the Zeppelin Observatory is the ideal place to help build up a picture of what is happening in the Earth's atmosphere. The sensors at the observatory measure not only greenhouse gases but chlorinated gases such as CFCs, airborne heavy metals, organophosphate pollutants such as pesticides, and pollution typically associated with burning fossil fuels such as nitrogen oxides, sulphur dioxide and particulates such as soot.
The data they collect is then added to measurements taken elsewhere by an international network of stations to build a global "background" of atmospheric gases, aerosols and particles in the atmosphere, giving a benchmark from which pollution is measured.
"The monitoring here at the observatory covers a whole range of issues," says Hermansen, who has been working at the Zeppelin Observatory for two decades. "Environmental toxins are particularly interesting for their biological effects and the state of the Arctic environment, while measurements of greenhouse gases and aerosols are especially important in a global context for their impact on climate change."
But the Zeppelin Observatory can also provide an early warning of changes that are taking place in the atmosphere.
Recently researchers have noticed growing levels of microplastics in snow samples in remote regions of the Arctic, suggesting that they may have been transported there by air
Levels of methane in the air around Zeppelin, for example, have been increasing since around 2005 and reached record levels in 2019. There is now growing concern that levels of human-caused methane emissions are threatening attempts to limit the amount of global warming to a 1.5C temperature rise.
Ten days after the Fukushima nuclear power plant accident in 2011, radionuclides – produced by the plant's fission reactor – were detected in the atmosphere at Zeppelinfjellet. It revealed that these radioactive particles were being carried thousands of miles through the atmosphere in just a few days.
The researchers at Zeppelin have also seen spikes in the levels of sulfate, particulates and metals such as nickel and vanadium in the air around Ny-Ålesund during the summer months due to growing numbers of cruise ships visiting the area.
They have also detected high concentrations of "aged" particles between March and May each year as weather patterns carry pollution from elsewhere in Europe and Asia. As soot moves through the atmosphere, for example, it undergoes a chemical reaction that makes the particles more reactive and increases their toxicity. Industrial smelters on the Kola peninsula in Russia also produce occasional spikes in metals like nickel, copper, zinc and cobalt in the air when the wind is blowing in the wrong direction during the winter and spring.
But it isn't always bad news. They have also seen levels of heavy metals such as lead and mercury decreasing, largely due to tightening rules on the burning of waste and industry. Efforts to reduce the use of organophosphate pesticides – which can get into the air when they are sprayed on fields – have also brought about a gradual decline in the amount of these chemicals being detected in the atmosphere around the Arctic.
Researchers must take a cable car to from the town to reach the observatory on the mountain, which has the benefit of a stunning view on the journey (Credit: Anna Filipova)
More recently, researchers have noticed growing levels of microplastics in snow samples in remote regions of the Arctic, suggesting that they may have been transported there by air. It has led the researchers at Zeppelin to monitor the atmosphere, and the snow falling there, for microplastics.
"Very small microplastic particles can travel considerable distances by air, similar to other particles that we already measure at Zeppelin," says Dorte Herzke, a senior researcher at Norwegian Institute for Air Research. "What is different for microplastics is that they are completely manmade, consist of very durable polymers and contain a broad mixture of chemicals, of which many are toxic. We are worried that microplastic particles are able to transport chemicals to the Arctic that otherwise would not be able to get there, potentially causing harm on the fragile ecosystems."
Yet while these intrusions from other parts of the world occasionally come to taint the air in this corner of the Arctic, it still remains far removed from the worst of the pollution humans release into the atmosphere. There are other places with air that could arguably be cleaner – in 2020 researchers discovered an extremely pristine layer of air over the Southern Ocean directly south of Australia. Ny-Ålesund is, however, one of the few such places that people can actually visit and live for a time, even if access is mainly limited to research scientists.
Ove Hermansen has studied air pollution for more than 20 years at the Zeppelin observatory, where researchers must also be on the look out for polar bears (Credit: Anna Filipova)
Surprisingly, it wasn't always this clean. Between 1916 and 1962, it was a coal mining town, until an explosion killed 21 miners, leading to the town being evacuated and the mine being shut down. Since then it has been transformed into a place where data is extracted from the environment rather than coal.
"Clean-ups have been carried out regularly since the 1960s when the mines were closed, but there is unfortunately still some pollution left both in the mining area and in the city," says Hanne Karin Tollan, a research adviser at Ny-Ålesund base, which is operated by a company owned by the Norwegian ministry of climate and environment called Kings Bay AS. "Kings Bay, which operates the entire settlement of Ny-Ålesund, has conducted environmental surveys to map pollution in the ground in the period 2019-2022 to uncover the extent and as a basis for further clean-up measures. All rubbish, waste and polluted soil is sent to approved receptions on the mainland Norway."
But while those working at Ny-Ålesund spend much of their time looking up to see what is in the air above their heads, life on the ground in the town is unusual. The residents come from all over the world including France, Germany, Britain, Italy, Norway, Japan, South Korea, and China, among others.
There are just two weekly flights to the town from Longyearbyen, Svalbard, which are offered in a bone-rattling propeller plane.
The town itself is comprised of about 30 cabin-like buildings named after large global urban centres: Amsterdam, London, Mexico, Italy – to name a few. They serve as a reminder of the need for diplomatic relations in this place far from the bustling crowds.
Other forms of connectivity, however, are less immediately available – all mobile phones and Wi-Fi must be turned off. The town is a radio-free zone in an attempt to keep the airwaves in the area as quiet as possible, and special permission is required for researchers who want to operate any equipment that uses radio transmissions.
Laser pulses from a Lidar instrument help to monitor aerosol levels and other pollutants in the atmosphere above Ny-Ålesund (Credit: Anna Filipova)
Among those taking advantage of the clear skies and radio-free environment is the Norwegian Mapping Authority, who have built a 20m (65ft) radio observatory there to help monitor the Earth's movements and gravitational field.
Violent storms often rattle the cabins of the town, and at night the wind sneaks inside to steal away residents' heat. During my visits to the town, most evenings I would wear all my outside clothes – expedition jacket, trousers, base-layer and mid-layer, topped off with a blanket – when inside the cabins.
Extreme weather is a hazard to all those who live and work here. The temperatures are often below freezing and the coldest ever recorded there was -37.2C (-35F) in winter. In March this year – during one of my own visits to Ny-Ålesund – temperatures reached a record high for the month at 5.5C (42F). The previous record was from 1976 at 5.0C (41F).
It is a stoic spirit that can handle the remote access, raw nature and harsh conditions along with long periods of either darkness or continuous sunlight. I was at the science station during the harshest time of the year, the dark polar night season, when there is 24-hour darkness for months.
Getting around meant using head-torches and moonlight. One young Italian PhD student I met walked alone through the black wilderness with only 2-3m (3.5-9.8ft) of visibility, facing strong winds and snow, just so she could change filters on some instruments.
But the dark also offers a fantastic views of the Northern Lights moving ghost-like across the sky above the town.
The community have a rule that no one can lock the doors of any building in case a bear appears inside the settlement and there is an urgent need for refuge
There are other dangers beyond the dark and the cold for researchers venturing out at this time of year. Svalbard is the natural habitat of the polar bear and over the years bears were seen close to the settlement, even passing through it. As a result, the community have a rule that no one can lock the doors of any building in case a bear appears inside the settlement and there is an urgent need for refuge.
"You have to adapt and work around the polar bears, not the reverse," says Christelle Guesnon, one of the researchers working at the Zeppelin Observatory for the Norwegian Polar Institute. "The bears like to follow the river and they often take the road between the Ny-Ålesund settlement and Zeppelin observatory. It happens quite often that we are up at the observatory and a polar bear is passing by. We then wait until the bear is gone."
After 16:30, the close of the working day, the small community tends to retreat indoors. Devoid of instant communication and mobile contact means relying upon arrangements made earlier in the day for any socialising. The town's canteen is the only place where people meet to spontaneously socialise during lunch and dinner hours, exchanging stories about the Northern Lights and the wildlife they encountered.
Many of those stories shared bear witness to changes that are happening in this remote Arctic ecosystem. Leif-Arild Hahjem, who has worked for many years in Ny-Ålesund as engineer for Norwegian Polar Institute, told me that he has been in the area since 1984 and has seen dramatic changes in the surrounding landscape.
Instruments dotted around the research station are used to take frequent measurements and their filters need to be changed (Credit: Anna Filipova)
"The fjord next to the settlement was frozen back then, you could go with a snowmobile but since 2006/7 it's no longer been frozen," he says. "The settlement is surrounded by many glaciers which are all getting smaller and most of that is due to increasing temperatures."
Rune Jensen, head of Norwegian Polar Institute in Ny-Ålesund, adds, with some sorrow, that in the 1980s an area known as Blomstrandhalvoya close to Ny-Ålesund was still believed to be a peninsula, but as the glacier has retreated over the last decade or so, it has become an island, cut off from the mainland.
"Today, we do experience the effects of a warmer Arctic in several areas," he says. "For example, the increased influx of warmer Atlantic water that alters the entire ecosystem in the fjord just outside Ny-Ålesund. It affects even the polar bears, which are forced to adapt their diet. Previously they used to catch ringed seals on the sea ice. Now we see a great rise in number of polar bears scavenging on eggs from seabird nests and catching seals from the land."
In the sky and landscape, the residents of Ny-Ålesund are witnessing the hallmarks of our changing world writ-large. For now, however, they can still breathe deeply in the knowledge that the air they are inhaling is a rare and precious resource.
* Anna Filipova is an environmental photographer and journalist based in the Arctic. She can be found tweeting at @Anna_Filip. This story was reported with support from the Judith Neilson Institute for Journalism and Ideas.
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