I grew up in Nepal’s capital watching the Himalayas. Ever since I left, I’ve missed sweeping, panoramic views of some of the highest mountain peaks on Earth.

Each time I visit Kathmandu, I hope to catch a glimpse of the dramatic mountain range. But these days, there’s usually no luck.

The main culprit is severe air pollution that hangs as haze above the region.

And it’s happening even during the spring and autumn months, which once offered clear skies.

Just last April, the international flight I was in had to circle in the sky nearly 20 times before landing in Kathmandu, because of the hazy weather impacting visibility at the airport.

The hotel I checked in at was at a reasonable height from which mountains are visible on a clear day – but there was no such day during my two-week stay.

Even from the major vantage point of Nagarkot, just outside Kathmandu, all that could be seen was haze, as if the mountains did not exist.

“I no longer brand the place for views of ‘sunrise, sunset and Himalayas’ as I did in the past,” said Yogendra Shakya, who has been operating a hotel at Nagarkot since 1996.

“Since you can’t have those things mostly now because of the haze, I have rebranded it with history and culture as there are those tourism products as well here.”

During an earlier trip a year ago, I was hopeful I would be able to see the mighty Himalayan peaks on a trek in the mesmerising Annapurna region – but had hardly any luck there either.

Scientists say hazy conditions in the region are becoming increasingly intense and lasting longer, reducing visibility significantly.

Haze is formed by a combination of pollutants like dust and smoke particles from fires, reducing visibility to less than 5,000m (16,400ft). It remains stagnant in the sky during the dry season – which now lasts longer due to climate change.

June to September is the region’s rainy season, when Monsoon clouds rather than haze keep the mountains covered and visibility low.

Traditionally, March to May and October to November were the best times for business because that was when skies remained clear and visibility was best.

But with rising temperatures and a lack of rain, and worsening air pollution, the spring months are now seeing thick haze with low visibility. Those conditions are beginning as early as December.

Lucky Chhetri, a pioneering female trekking guide in Nepal, said hazy conditions had led to a 40% decrease in business.

“In one case last year, we had to compensate a group of trekkers as our guides could not show them the Himalayas due to the hazy conditions,” she added

An Australian tourist who has visited Nepal more than a dozen times since 1986 described not seeing the mountains as a “major let-down”.

“It wasn’t like this 10 years ago but now the haze seems to have taken over and it is extraordinarily disappointing for visitors like me,” said John Carrol.

Krishna Acharya, the provincial chair of the Trekking Agents Association of Nepal in the western Gandaki province, says the trekking industry is in deep trouble.

“Our member trekking operators are getting depressed because no sighting of the Himalayas means no business. Many of them are even considering changing professions,” he told the BBC.

On the Indian side, near the central Himalayas, hoteliers and tour operators say haze is now denser and returns quicker than before.

“We have long dry spells and then a heavy downpour, unlike in the past. So with infrequent rain the haze persists for much longer,” said Malika Virdi, who heads a community-run tourism business in the state of Uttarakhand.

However, Ms Virdi says tourists are persistent – with many who didn’t catch the mountain range returning to try their luck again.

The western Himalayas in Pakistan have been relatively less affected by the haze because the mountains are relatively far from cities.

But locals say that even the ranges that were once easily visible from places like Peshawar and Gilgit are often no longer seen.

“The sheet of haze remains hanging for a longer period and we don’t see the mountains that we could in the past,” said Asif Shuja, the former head of Pakistan’s environmental protection agency.

South Asian cities regularly top lists of places with highest levels of air pollution in the world.

Public health across the region has been badly impacted by the toxic air, which frequently causes travel disruption and school closures.

Vehicular and industrial emissions, dust from infrastructure construction and dry gravel roads as well as the open burning of waste are major sources of air pollution year-round.

This is compounded by soot from massive forest fires – which are increasing due to a longer dry season – and the burning of crop residues after the harvest by farmers in northern India, Pakistan and Nepal.

Weather conditions keeping warmer air above cooler air trap these pollutants and limit vertical air movement – preventing pollution from dispersing.

“Hazes and dust storms are increasing in South Asia, and this trend is projected to continue due to climate change and other factors,” Dr Someshwor Das from the South Asia Meteorological Association told the BBC.

In 2024, the number of hazy days recorded at the airport in Pokhara, a major tourism hub in western Nepal, was 168 – up from 23 in 2020 and 84 in 2021, according to Nepal’s department of hydrology and meteorology.

Experts believe the Himalayas are probably the worst affected mountain range in the world given their location in a populous and polluted region.

This could mean the scintillating view of the Himalayas could now largely be limited to photographs, paintings and postcards.

“We are left to do business with guilt when we are unable to show our clients the mountains that they pay us for,” said trekking leader Ms Chhetri.

“And there is nothing we can do about the haze.”

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