Walking in the North Pennines. Paddy Dillon

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СКАЧАТЬ The best time to walk easily across wet blanket bogs is during a hard frost when they are frozen solid!

      The Helm Wind

      Most visitors to the North Pennines hear about the Helm Wind, but few really understand what it is. The Helm Wind is the only wind in Britain with a name. It only blows from one direction, and gives rise to a peculiar set of conditions. Other winds may blow from all points of the compass, from gentle zephyrs to screaming gales, but the Helm Wind is very strictly defined and cannot be confused with any other. (The last time the author explained how the Helm Wind operated, a film producer from Australia beat a path to his door to make a documentary about it!)

      To start with, there needs to be a northeasterly wind blowing, with a minimum speed of 25kph (15mph), which the Beaufort Scale describes as a ‘moderate breeze’. This isn’t the prevailing wind direction and it tends to occur in the winter and spring. Now, track the air mass as it moves off the North Sea, across low-lying country, as far as the Tyne Gap around Corbridge. The air gets pushed over Hexhamshire Common, crossing moorlands around 300m (1000ft). Next, it crosses the moors above Nenthead, around 600m (2000ft). Later, Cross Fell and its lofty neighbours are reached, almost at a level of 900m (3000ft). There are no low-lying gaps across the North Pennines, so there is nowhere for the air mass to go but over the top.

      As the air has been pushed ever-upwards from sea level, it will have cooled considerably. Any moisture it picked up from the sea will condense to form clouds, and these will be most noticeable as they build up above the East Fellside. This feature is known as the Helm Cap, and if there is little moisture present, it will be white, while a greater moisture content will make it seem much darker, resulting in rainfall. Bear in mind at this point that the air mass is not only cooler than, but also denser than, the air mass sitting in the Vale of Eden.

      After crossing the highest parts of the North Pennines, the northeasterly wind is cold, dense, and literally runs out of high ground in an instant. The air literally ‘falls’ down the East Fellside slope, and if it could be seen, it would probably look like a tidal wave. This, and only this, is the Helm Wind. The greater the northeasterly wind speed, the greater the force with which it plummets down the East Fellside, and if it is particularly strong, wet and cold, it is capable of great damage. Very few habitations have ever been built on this slope, and the villages below were generally constructed with their backs to the East Fellside, rarely with doors and windows in them until the advent of modern draught-proofing.

      The air mass now does some peculiar things, having dropped, cold and dense, to hit a relatively warm air mass sitting in the Vale of Eden. A ‘wave’ of air literally rises up and curls back on itself. As warm and cold air mix, there is another phase of condensation inside an aerial vortex, resulting in the formation of a thin, twisting band of cloud that seems to hover mid-air, no matter how hard the wind is blowing at ground level. This peculiar cloud is known as the Helm Bar, and is taken as conclusive proof that the Helm Wind is ‘on’, as the locals say.

      Local people always say that no matter how hard the Helm Wind blows, it can never cross the Eden. All the wind’s energy is expended in aerial acrobatics on the East Fellside, where it can roar and rumble for several days, while the Vale of Eden experiences only gentle surface winds. Northeasterly winds are uncommon and short-lived, so after only a few days the system begins to break down and the usual blustery southwesterly winds are restored. In the meantime, don’t refer to any old wind as the ‘Helm Wind’ until all its characteristics have been noted, including the northeast wind, the Helm Cap and the Helm Bar.

Plants and wildlife

      Although the North Pennines today features extensive moorlands, this was not always the case. From time to time, eroded peat hags reveal the roots of ancient trees – the remnants of the wildwood that once covered all but the most exposed summits. Only hardy species such as juniper or dwarf willow can survive in exposed upland areas, though some of the dales feature mature woodlands, and some marginal areas have been planted with commercial conifers. It may seem strange, but woodland plants can thrive in areas far removed from woodlands, simply by adapting to the shade provided by boulders or other taller plants. One of the best remnants of the original wildwood can be seen around Allen Banks and Staward Gorge, along with the juniper thickets of Upper Teesdale.

      Many visitors are delighted to visit Upper Teesdale in spring and early summer, where the peculiar Teesdale Assemblage of plant communities is seen to best effect. Remnant arctic/alpine plants thrive on bleak moorlands – such as cloudberries on the boggiest parts. Drier areas, particularly where the soil is generated by the crumbly ‘sugar limestone’ on Cronkley Fell and Widdybank Fell, feature an abundance of artic/alpines, including the delightful spring gentian and mountain pansy. Other plants thrive in hay meadows, because haymaking traditionally starts late at Upper Teesdale and Weardale, allowing seeds to mature and drop before mowing. A trip to the Bowlees visitor centre is a fine way to get to grips with the nature and floral tributes of the region before setting off walking and exploring.

      Extensive heather moorlands in the North Pennines are essentially man-managed

      Cloudberries are arctic/alpine remnant plants that thrive on the boggy slopes of Mickle Fell (Walk 13)

      Upper Teesdale boasts a fascinating assemblage of wild plants, including the mountain pansy (Walk 27)

      Bear in mind that the extensive grass and heather moors of the North Pennines exist only because of human interference. Grassy moorland was developed as rough pasture for sheep grazing, while heather moorland was developed to provide food and shelter for grouse, to maintain a grouse-shooting industry. There should be a greater range of species on the moors, including trees and scrub woodland, but these are suppressed by grazing and rotational burning. Vegetation cover can change markedly when underlying sandstone gives way to limestone.

      Most of the animal life you will see around the North Pennines is farm stock, although deer are present in some wooded areas, where they might be observed grazing along the margins of woods and forests at dawn and dusk. Britain’s most northerly colony of dormice is found at Allen Banks, and the elusive otter can be spotted, with patience, beside rivers and ponds. Reptiles are seldom seen, but adders, grass snakes and common lizards are present. Amphibians such as frogs are more likely to be seen, while toads and newts are much less common.

      Birdlife can be rich and varied, but the North Pennines is notable primarily for their population of red grouse. Rare black grouse can occasionally be spotted, especially during the mating season, when they perform elaborate displays on particular parts of the moors. The placename ‘Cocklake’ is derived from ‘cock lek’, and refers to the mating displays of black grouse. For details see www.blackgrouse.info.

      Late spring and early summer are important times for breeding birds. Cuckoos will be heard as they advance northwards, while skylark, lapwing, snipe and curlew are often seen on broad moorlands. Watch out for buzzards, merlins and kestrels in open areas, and red kites around Geltsdale in particular. Herons fish in watercourses, while dippers and grey wagtails will completely submerge themselves in rivers. Some gulls and waders travel from the coast to the Pennines, and it is not unusual to find raucous colonies of gulls around shallow pools high on the moors.

      The enormous Upper Teesdale and Moor House national nature reserves often feature guided walks with wildlife experts. Look out for their annual events guide, which runs from March to October, with a special emphasis on the spring and summer. These reserves claim to be the most scientifically studied upland regions in СКАЧАТЬ