The High Alps in Winter
Weather Conditions.
The weather after the New Year is usually more settled than in the summer. A spell of absolutely unbroken weather lasting from three weeks to a month or more is almost inevitable some time in January or February. As a rule, February is the finest month in the winter.
These typical fine-weather periods are often accompanied by mild weather. The temperature even by night is often surprisingly high on the glaciers, even when there is no touch of Föhn in the air. This has led some observers to claim that the temperature in winter—even in the shade—is often lower in the valleys than on the mountains. I have never seen any evidence produced for the phenomenon which has been romantically described as ‘inverted temperature,’ and have no reason to believe that any such violation of the laws of temperature really exists. It is often, of course, colder in the plains when the plains are covered by nebelmeer than in sunny alpine stations, but this is very different to any general inversion of temperature. I have, it is true, sat on the summit of the Finsteraarhorn in midwinter stripped to the waist, and I have often been uncomfortably hot at great altitudes in the sun. But it is dangerous to generalize from such experiences, and though on a windless day, winter mountaineering may be as warm and comfortable as summer climbing, the ski-runner must always be prepared for sudden danger of temperature, and severe cold.
The variations in temperature are surprising. A cushion of cold air, several degrees below freezing, may exist near the surface of the snow, and three feet above the surface of the snow the air may be quite mild. This is a phenomenon well known to rink-makers. In the sun the heat may be quite intense, and yet, a few yards off, in the shade the temperature may be several degrees below freezing.
A suspicion of wind may transform a mild and equable into an unpleasantly cold atmosphere. The changes of temperature are very sudden. You may be basking in shirt-sleeves on one side of a ridge, and be frost-bitten within a few minutes on turning a corner into the wind.
The great danger of winter mountaineering is the risk of a sudden change of weather. Storms seem to blow up out of clear skies with a suddenness to which summer affords no parallel. The man who is caught in a big winter storm is lucky if he escapes without casualty. A driving wind makes ski-ing almost impossible. The snow is blown into one’s face, and in a few minutes one’s eyelashes are gummed up with miniature icicles.
The big storms that sometimes prevail for more than a week at a time may imprison the climber in a club hut until all his provisions are exhausted. From most club huts escape is completely impossible till the storm drops. Even when the storm has given place to fine weather, retreat may be very dangerous owing to the avalanche peril.
Under fair conditions winter mountaineering is often surprisingly easy. Men who have enjoyed unbroken good luck with their weather are tempted to discount the very real dangers of mountaineering in winter, and to adopt a paradoxical attitude towards the Alps in winter, implying that the only danger to be feared is sunstroke and snow-blindness. Those who have not been so uniformly lucky realize that winter mountaineering on a big scale is a sport from which the element of danger will never be lacking; that a sudden storm may transform even an easy expedition into a desperate struggle for safety.
The Approaches to the High Alps.
Often the most difficult, and sometimes the most dangerous, part of a winter expedition in the High Alps is the first day’s march to the club hut. Once the upper regions are attained, progress is usually fairly straightforward. It is quite normal for ski-runners to make nearly as good time on the ascent of a snow-peak as summer climbers, but it is very rare indeed that the club hut is reached in anything approaching summer time. From one and a half to twice as long must be allowed for the ascent to most club huts.
The long, narrow valleys that so often lead to huts are usually very deep in soft powdery snow, so that progress must be slow, whereas in the upper regions the snow is usually more or less packed by the wind, which makes for easier going on the ascent, even though the descent may be far from pleasant. Moreover, the danger from avalanches is usually much more serious in the lower regions, where the slopes are much steeper and the valleys narrower.
On the first day’s march the guides will be heavily loaded, for the full equipment for a serious expedition in the High Alps is very much more bulky and weighty than that necessary in summer. In the first place, no prudent ski-runner commits himself to a High Alp tour without ample reserves of food. He must allow for the danger of finding himself stormbound in a hut for a period which may be anything from a day to a fortnight. Plenty of compressed reserve food is essential until the club huts begin to store emergency rations. Further, as a broken ski may involve serious consequences, he must burden himself with spare ski-tips and all the apparatus for mending ski. Extra clothes, plenty of gloves, and, of course, crampons add to the overburdened rucksacks. Unless one is prepared to carry very heavy sacks it does not pay to economize in porters. As a rule, you should reckon two guides or porters for every member of the party if you contemplate an expedition of some five to six days in length, unless, of course, you are prepared to carry some thirty pounds or so in your own sack for the first day. Of course, if you take two porters to the hut, they may be sent back from the hut; but it is obviously unfair to expect a solitary porter to make the descent alone.
Everything should be done to make matters easy. If the first part of the ascent lies up a path or a wood-track, a boy should be hired to carry your ski. If the ascent begins from some out-of-the-way alpine valley, it will often pay to send a guide on ahead the day before to make tracks for part of the distance in soft snow. This is especially useful if you are attempting a very big climb from one of the rather higher alpine valleys or mountain inns without using a club hut. It is unwise to reckon on climbing more than an average of 500 feet per hour for the first day.
An early start is essential. The longest days pass fairly comfortably if you break them up with frequent short halts and short feeds. It is often impossible in winter to make a prolonged halt owing to the cold. A few caramels or some chocolate, which can be easily got at, should be kept in one’s pocket, and munched during short halts. Napoleon’s rule of a short rest and something to eat every hour is a good rule for climbers, especially winter climbers who are heavily laden.
The huts as a rule are comfortable enough in winter, though the stoves often prove troublesome. Wood is usually kept in large quantities, brought up at the end of the autumn, though it is as well to make inquiries on this point before starting. On reaching the hut, set the aneroid barometer usually found in most huts. A pocket-barometer is not so reliable, for, as Whymper pointed out and conclusively proved, the usual aneroid tends to lose on the mercurial. In other words, if you carry a pocket-aneroid up some thousands of feet and then set it at the hut, it will usually fall a point during the night, where a mercurial barometer would have remained stationary.
So, too, if you descend from a peak to a hut, the pocket-aneroid will rise where a mercurial would remain stationary, thereby often conveying very dangerous and misleading information. It is most important to set the hut aneroid, so as to have some warning of the approach of a sudden storm.
If you are unlucky enough to be caught by bad weather in a hut, and if your provisions run short, you should spend as much of your time as possible lying down and keeping warm, for the less exercise you take the less food you will need. People who practise the ‘fast cure’ have proved that a man can go without any food for a week and carry on his ordinary business without feeling unduly weakened. It is therefore in every way better to stay at the hut fasting—even for three or four days—than to attempt to descend in a bad storm. If the worst comes to the worst, and the party is thoroughly weakened by lack of food, they can always stay at the hut and await the search party.
If a sally is attempted in bad weather from a hut which is situated among glacier snow-fields, it is advisable to cut up a number of small stakes from the firewood. These can be planted in the snow at intervals of a hundred yards or so in order that a retreat can always be made back to the hut if further advance is impossible.
Snow Conditions in the High Alps.
If the Alps were windless, the snow that falls between November and the end of February would remain powdery and unspoiled on all save very steep south slopes. At high altitudes the sun is powerless to affect the snow in midwinter on gentle south slopes. The snow would remain powdery on northern slopes till the middle of April but for wind. Unfortunately, the High Alps are swept by wind, more especially during long spells of fine cloudless weather, during which the ‘bise,’ or north wind, sweeps across all exposed ridges and faces. Consequently, the snow seldom remains long unspoiled. In sheltered glacier valleys it may retain its powdery condition, but on all more or less exposed slopes it soon hardens. Of course, if an expedition is planned within two or three days of a fresh snowfall, the party may have perfect powder snow; but such snow is the exception in winter in the High Alps, whereas it is the rule in spring.
Rock Ridges and Ice Slopes.
Rock climbing does not properly come within the scope of mountaineering on ski; but so many ski-runners combine a ski tour with a final scramble up a rock ridge, such as the last arête of Monte Rosa or the Zinal Rothhorn, that some discussion of the condition of rocks and ice slopes in winter is essential.
As a rule, rock ridges are as dry, or drier, in winter than in summer. Snow that falls in summer often falls at a temperature little below freezing. It is often most adhesive stuff. The strong summer sun followed by frosts at night turns this snow into crust, or at least into snow with a considerable power of sticking to the rocks. In summer it is often several days before the big rock peaks will go after a heavy snowfall. But in winter the snow that falls in the High Alps is light and powdery. The low temperatures and the reduced power of the sun prevent the snow melting; it retains its light powdery character, and is swept away from exposed ridges by the wind. It offers no resistance to the wind, for it is composed of light dry crystals with no cohesive or adhesive power. Consequently, the rock ridges in the winter are often freer from snow than in average summer weather, which is a mixture of good and bad. In winter, cornices have little chance of forming. In fact, if the weather is mild and the ridge windless on the day of the ascent, it is scarcely more difficult to climb a rock ridge of average difficulty in winter than in summer. South ridges are, of course, much warmer than north ridges, but they are not necessarily more free of snow; for the agent that reduces the snow on the rock ridges is not the sun—powerless as a melting agent at these altitudes in winter—but the wind; and in fine weather the wind, as often as not, blows from the north. Of course, if the north wind is blowing, a north ridge may be impossible, for the rocks promptly become extremely cold to touch, so that in general it is wisest to select south rock ridges in preference to north. None the less, rock ridges facing north, such as the north ridge of the Zinal Rothhorn or the north ridge of the Gspaltenhorn, have been climbed without difficulty in midwinter.[22]
The same causes which keep the rock ridges comparatively free from snow tend to remove any snow that may fall on to steep ice slopes.
Inexperienced winter mountaineers are often surprised to find as much or more ice on summit slopes in winter than in summer.
As a matter of fact, there is often quite as much ice on steep exposed slopes in winter as in summer.
An ice slope is transformed into a snow slope when falling snow is accompanied by a temperature just above freezing-point—in other words, when the snow is very nearly sleet. Such snow adheres to the underlying ice, and by the normal process of alternate thaw and frost becomes more and more firmly attached. The next snowfall that occurs attaches itself to the underlying thin stratum of snow crust lying on ice, so that in the course of time the ice slope is covered by a compact and reliable layer of crusted snow.
But the dry powder of midwinter has no chance of finding a permanent resting-place on steep ice. The first strong wind that blows will remove it.
Many slopes vary from season to season and from month to month. Sometimes they are ice, sometimes snow. Such slopes, if they are ice in October, will remain ice until the following spring. May and June are the months in which the conversion of ice slopes into snow slopes usually takes place.