Captain moonlight: A new exhibition of Darren Almond's ethereal, nocturnal images is about to open at White Cube

The Turner-Prize nominated artist Darren Almond points to the faint line of light streaking across a photograph of Ribblehead Viaduct on the Settle-to-Carlisle railway. Cutting through the misty landscape, it marks the journey of the night mail-train from Scotland, captured in a long exposure that was lit only by the moon. "I was jumping for joy when I heard the train coming," says Almond, 36, as well he might – as a child growing up in Wigan, he was trainspotter.

Timetables, the steady flip of station digital clocks and waiting, waiting, waiting – as unlikely as it seems, that much-maligned hobby and its banal motifs have been good grounding for Almond's career as a conceptual artist, which took off in the late 1990s as part of the post-YBA generation tended by Jay Jopling's White Cube gallery.

In any case, Almond's nerdy days are well behind him, as his CV demonstrates. For Sensation, at the Royal Academy in 1997, he constructed an enormous digital clock and amplified the sound of the relentless click-clack of the passing minutes. In 2000, for the hip Matthew Marks Gallery in New York he made an even bigger clock, the size of a shipping container, freighted it across the Atlantic and then finally docked it at the Venice Biennale in 2003.

The work that got him nominated for the Turner in 2005 took a turn for the serious, with photographs and video that meditated on the visible effects of passing time on fragile wildernesses in Antarctica. Also included were photographs of moonlit landscapes – and it is 50 new colour prints from that ongoing Fullmoon series that comprise his new show at Jopling's Hoxton outpost, White Cube, where we met.

All photographed in the British Isles and Ireland, this insomniac's tour starts with the seething blue seas at rocky Malin Head, goes via dramatic gorges of Gordale Scar of Dartmoor and on to thick ferns and mountains of Wester Ross in the Highlands. The first thing that you notice is that the landscapes don't look moonlit at all. The sky is blue, or appears hazy with sunshine, and although there is a surreal quality to the fuzzy mists that hang in the air, and the seas and rivers resemble a seething brew of dry ice – okay, that's quite strange – the bright colours of plants, rocks and trees all suggest daylight. Maybe I've just watched too many night-vision real-life crime reconstructions, but looking at these pictures you realise how ridiculous it is to think that night-time is monochrome. Using exposures from 15 to 45 minutes long (and the patient wait is part of the pleasure for him) Almond's medium-format camera soaks up all the light reflected off the moon, creating sublime new landscapes that convey a long meditation rather than quick snap.

But, while it's fun to search for the tiny white lines in the sky that show the progress of a star over a 40-minute exposure, is there much else in these photographs, which at times come dangerously close to the simply picturesque?

Initially, Almond says, the landscapes he chose were indirect references to Romantic paintings. Starting in Cézanne country, then in Turner's Alps and finally Constable's Flatford, (the location for The Haywain and included in this show), Almond revisited the sites of masterpieces in the dead of night.

"I thought the series would end at that, but I got sucked into the whole process of making photographs in moonlight," he says. There is, however, a subtle ecological aspect to Almond's artistic practice. These landscapes are disappearing, he says, "because we're farming so much," and while one might take issue with that (a good proportion of the photographs here show sheer rockface), the technique he employs certainly illustrates how light pollution is encroaching even in rural areas.

"When I moved to London I really started to miss the moonlight and my relationship with the moon. Every night you were flooded with sodium and it was almost like someone had stolen the moon from me, and I wanted to go back and find it again. I longed for it." Even in the remoter regions of Britain, Almond says he struggled to find locations that were beyond the reach of artificial light.

If the creeping urbanisation of the British Isles is an issue only faintly detectible at the White Cube show, Almond makes more overt political statements at a not-for-profit exhibition at Parasol Unit in Islington, which opens simultaneously. Comprising video, photographs and sculpture (in other words, more digital clocks, this time in multiples and all clicking with menacing synchronicity), the main draw of this exhibition is a triptych film that protests at the cultural invasion of Tibet by China.

Showing, on the one hand, the mountainous view seen through a window on a train journey between the two countries on the newly-built Qinghai-Tibet railway (the world's highest train-route) and also Tibetan monks singing prayers, Almond mourns the gradual erosion of Tibetan culture as visitors from mainland China immigrate.

Equally confrontational are Almond's enormous series of black-and-white photographs showing blackened trees on the Siberian tundra outside of Norilsk. The town was the site of a notorious gulag and, more recently, home to the world's largest nickel mine. After spewing out sulphur unchecked, trees in the area have effectively been chemically burnt, and now resemble sad sticks of charcoal poked in the snow.

"You get these forests of dead, burnt, trees on a landscape that's never dry," says Almond, "It's totally incongruous." Almond spent months at a time in the town, contemplating the human and environmental loss (the residents' average lifespan is 10 years less than other Russians) and enduring temperatures of minus 45F. At times, he says, the liquid in his eyes froze. A second film, running for more than 30 minutes, shows workers at the face of an Indonesian sulphur mine, clouds of puce-coloured gases enveloping people as they struggle to carry rocks from a crater, with only rags to cover their mouths.

These works are not exactly a call to action, says Almond, but provocative subjects that he chooses to observe. The viewer is left to watch in a state of half-informed helplessness. As British contemporary artists rarely engage with current affairs, let alone political or environmental issues, Almond's works are pleasingly engaged with the world at large. "It's like we're in a vortex that's speeding up, a whirlpool," says Almond of the ever-increasing load of horrifying information we are given about the destruction of the planet. "The political and social issues are there in my work because they're current. This is the emotional landscape that surrounds me."

Darren Almond, Moons of the Iapetus Ocean is at White Cube, 48 Hoxton Square, N1 from tomorrow to 23 February;Fire Under Snow: Darren Almond is at Parasol Unit Foundation, 14 Wharf Road, London N1 from tomorrow – 30 March

'Night and fog'

"Norilsk has one of the biggest nickel mines in the world. There's more acid rain in this town of 150,000 than in North America and Canada. The trees suffer something similar to frostbite. You get these forests of dead, burnt trees in a landscape that's never dry so it's totally incongruous. It got down to minus 45C. My eyeballs froze" – DA

'Fullmoon@Wester Ross'

"When I moved to London I really started to miss the moonlight and my relationship with the moon. Every night you were flooded with sodium. I wanted to go back and find it again. I longed for it. There's something about the light in these photographs that isn't daylight. You're not quite sure whether this landscape actually exists – it looks fictitious or overly ideal. There's a strange kind of depth of field and quality of the light that keeps you trapped in." – DA