I set out on my usual lockdown run, expecting to tread the same paths. But as soon as I leave the town and climb a little up the Chevin ridge, I find myself in an entirely new landscape. The paths through the wood have become snow tunnels, and the usual ambient noise of cars on the roads in the valley below is suppressed. The result is a muffled, monochrome world that exists in its own fragile reality. The snow gilds everything, from the forest floor to the very twig-tips of the beech trees, on which tufts of frosting balance as if they weigh nothing. It feels like the slightest sigh of wind could dislodge the snow from these spindly branches, but the stillness is so complete it somehow stays in place, turning the web of the wood’s canopy into a mesmerising black and white filigree. This blast of Siberian air seems to have unmoored the landscape and transported it somewhere else entirely, freeing it from its usual altitude and latitude. In my imagination, at least, these steep, snowbound woods and the rime‑encrusted Millstone Grit outcrops that dot the escarpment in this corner of West Yorkshire could be part of an Alpine forest, or a boreal wilderness somewhere in Scandinavia or North America. I do find a hint of colour though. In the depths of a ghyll, the slopes are dominated by large clumps of male ferns (Dryopteris filix-mas). These dark green fronds wouldn’t be out of place in a Cretaceous jungle, but with a dusting of snow they look somehow fantastical, a collision of the tropics and the Arctic. With our horizons narrowed again by lockdown, these flights of fancy are a welcome relief from geographical normality. I come to a stop in a heath near the top of the ridge where a glimmer of movement in the frozen scrub catches my eye. It is a small, energetic flock of long-tailed tits (Aegithalos caudatus) – tiny, flying balls of fluff combing assiduously through the bare foliage, gleaning what food they can from the landscape. These birds are known to have a hard time in winter. I watch their labours for a while, before the cold forces me on.