September 2003Brocken Spectre Chasing
The Mystical Haloed Shadow
You are picking your way along the ridge, aware only of the ground and the damp, and possibly of the drop that is hidden behind the shrouding mists and cloud. Suddenly the sun breaks through brightly behind you. Cloud lingers on the lee of the crest, and a large shadow looms before you, floating, fleeting, ethereal, surrounded by a series of coloured rings, halo-like and mystical. You stand, enthralled. You realise that the shadow is your own. It shimmers, and is gone as the sun is once more obscured. Other people ahead of you on the ridge are waving at nothing. They have seen the Spectre too, but only theirs.
The name Brocken Spectre originates from the highest top in northern Germany, the Brocken in the Harz mountains, where legend has it that a climber fell to his death after being startled by the unearthly appearance of a haloed human figure in the swirling mists. The shadow, of course, was his own, cast by the sunlight onto the cloud. And the halo was the Glory ring, formed by the scattering of sunlight backwards from the tiny water droplets that make up mist or clouds.
Spectre Chasing
No walker will ever forget their first experience of seeing a Spectre. I know a number of people who have yet to see one in many years of walking the hills, but Spectres are surprisingly common if you know the conditions in which they occur and can make your own luck. On one occasion we were walking west from Pillar in the Lake District, and noticed that mist was lingering below us in Mosedale to the south. As the afternoon sun was in the south-west, we needed to place ourselves between the sun and the mist, and made a deliberate detour onto the Red Pike ridge in order to "catch" the Spectre in this image right. Read Technical Details here ...
Brocken Spectres often appear from mountain ridges when the ridge is clear and the corrie below you is filled with mist, or when the sun suddenly breaks through the mist. Your shadow is cast onto the mist, always around the anti-solar point, exactly opposite the sun. Narrow ridges with deep corries like Crib Goch offer great opportunities on winter days with bright sunlight and lingering clouds, especially in the afternoon.
On one magical day in December 1989 we were fortunate enough to see dozens of Spectres from Crib Goch in Snowdonia, including the one at the top of the page and this one, left. As the mist closed in and opened up, it was often possible to see other walkers ahead of us waving their arms to give a more distinctive shape to their shadows. The glory rings are less distinct here, and are more reminiscent of "Heiligenschein", another similar scattering effect. Often, with no visual reference point, the shadow can look enormous,
but close to the sunlit rocks of the ridge, the shadow assumes more realistic proportions.
Unusual Spectres
This Spectre was one I observed from Yr Aran in Snowdonia in November 1994, and was made with a standard 50mm lens. It appeared when I was least expecting it because the mists were hardly visible, and the sun broke though for only a few seconds. Feeling it was unusual, I made contact with Les Cowley from Atmospheric Optics. Here's
what he had to say:
[This] Brocken Spectre and glory ... is intriguing. The shadows are against solid ground which makes them stand out, but I do not recall coming across such bright surrounding glories from very thin mist. I would guess that this [Brocken Spectre and glory] was formed from fresh mist having droplets of uniform size (because three glory rings are visible and differing droplet sizes would blur the outer ones out). At the level of the shadow of your head the droplets were only 6.4 micron diameter: 10 - 30 is more the usual run of mists. The mist was also stratified; notice that the first red ring is not circular but has a greater radius above the head shadow and less below. The mist droplets were noticeably smaller with increasing height. The lesson to would-be Brocken hunters is to look out for them even when mist is thin. Somehow these images are more 'spooky' than the conventional shadows looming in thick mist, perhaps because they are unexpected.
Thanks Les, for this fascinating insight. Read Technical Details here ...
More Pics
Here are two more pics from that remarkable day on Crib Goch. In both we can see the shadow of the ridge itself and multiple human shadows, of me in the centre and of my companions. This emphasises how we each can see only our own glory rings; the others would have seen the rings centred around themselves.
The three-spectre image, left, was lit by a very weak sun and has an indistinct glory, so I have pumped up the contrast to illustrate the multiple shadows. In the image, right, the second walker is creeping into the shadow range from the left.
Other Spectre Stories
Another legendary mountaineering story about atmospheric phenomena is that of Edward Whymper's ill-fated first ascent of the Matterhorn in 1865. Tragedy struck the team on their descent from the summit when four fell to their deaths. Later that evening Whymper saw a vision in the sky resembling a circle of light with three crosses. Naturally in the circumstances, Whymper linked his vision to a spiritual visitation. What he had actually seen was an atmospheric display of either a fogbow or a more complex ice halo.
Links and Resources
You don't have to be a mountaineer to see and enjoy atmospheric effects. Keep your eyes peeled when flying above the clouds in an aircraft, and you will have a very good chance of seeing the "Brocken Spectre" shadow of the aircraft with glory rings on the cloud below you. Sun and lunar haloes, irridescence in the clouds and sundogs are all common in the UK wherever you are.
To find out more about all these atmospheric optical displays, visit Les Cowley's Atmospheric Optics, a fantastic site covering a vast array of effects, with superb images, detailed scientific explanations and simulation software.
Philip Laven's Optics of a Water Droplet also contains a wealth of fascinating explanations for atmospheric effects, including Brocken Spectres and Glories.
Page 1 of 1: Previous 1 Next
