The higher or the better?: Chris Gill and his computer work out which resorts should offer the most reliable skiing

ONE OF the notions skiers have grown used to is that high resorts are relatively sure of snow. If there is natural precipitation, it is more likely to be crystalline at high altitudes; and if there is not, snow-making is more likely to be possible (water supplies permitting).

There are drawbacks to high resorts - the absence of trees makes skiing impossible when snow is falling. And many high resorts are not particularly pleasant places at the best of times. But leaving these reservations aside, the advice to go high prompts another question: what is a high resort? This was brought to mind by the announcement of a friend - not a highly experienced skier - that after disappointing conditions two years running she was planning to go high this year - to Avoriaz.

Avoriaz is the classic case of a high resort - around the 1,800m mark - surrounded by not very high skiing. It takes only a minute's study of the piste map to see that most of the lifts go no higher than 2,200m, while quite a lot of the skiing is below the resort altitude. My friend hadn't spent that minute with the map.

The very top height of the skiing around Avoriaz is only 2,275m, so even the resort statistics quoted in the tour operator's brochure should have been enough to sound the alarm. But there are other resorts that are more deceptive.

Many have top lifts that go to extreme altitudes and so make the resort look good on paper. If these lifts carry very few people, or serve very little skiing, or serve only difficult runs, or serve only absurdly easy runs, their top altitudes are misleading. What matters more is the altitude at which most skiers will be spending most of their time. I have been poring over the piste maps trying to arrive at a numerical indicator of this altitude.

In some resorts, the whole of the ski area between the village and the top of the top lift is effectively open to most skiers. In these cases, the average of the top altitude and the resort altitude gives a reasonable guide to how high you'll be skiing. In resorts where the top lifts are in some way extraordinary, it makes better sense to take a lower top height. If in practice skiers spend their days on the top half of the mountain rather than descending repeatedly to the village, taking a higher bottom figure makes better sense than taking the village height. And if - as in Avoriaz - a lot of skiing goes on below the village, a lower bottom height is more representative.

Feed all this into a computer spreadsheet and you can calculate an accurate Average Skiing Height. For the 38 resorts I have done this for, the ASH ranges from 1,325m for Schladming to 2,975m for Saas Fee. So far, so good. But if we are after a guide to snow conditions, altitude alone is not enough.

The further east you go (the further from the Atlantic), the more severe the winter weather; the further south, the less severe. So I have used a correction factor, taking northern France as the starting point and adding 200m to the ASH for resorts in eastern Austria, less for the central Alps, and deducting 50m for the southern French Alps.

The resulting Corrected Index of Average Skiing Height (effective skiing height) is shown in the table. Avoriaz comes near the bottom, but what is striking is that the height of the resort is almost the same as its CIASH, whereas the other resorts with a CIASH around 1,900m are appreciably lower; the same is true of Isola 2000. At the opposite extreme, in the cases of Schladming, Kitzbuhel and Chamonix, the index is more than twice the resort height.

The table also shows the limits of 'normal' skiing that I have based the calculation on - the crucial factor. I offer these figures not only to fuel bar-stool debates, but to invite feedback. Does the CIASH fit with your experience? Should a bigger or smaller correction factor be applied? What other factors need to be allowed for? And have I been fair to the resorts which you know and love?

---------------------------------------------------------------------- Forget the resort height: how high can you ski? ---------------------------------------------------------------------- Resort Highest Normal ski range Avge Weather Effective height skiing Top Bottom skiing factor skiing height height ---------------------------------------------------------------------- Saas Fee 1800 3500 3500 2450 2975 0 2975 Val Thorens 2300 3200 3200 2100 2650 0 2650 Val d'Isere 1850 3500 2800 2300 2550 0 2550 St Moritz 1800 3300 2700 2200 2450 100 2550 Obergurgl 1930 3035 3000 1900 2450 100 2550 Zermatt 1620 3900 3100 1900 2500 0 2500 Verbier 1500 3330 2950 2000 2475 0 2475 Cervinia 2050 3490 2900 2050 2475 0 2475 Tignes 2000 3500 2800 2100 2450 0 2450 Ischgl 1400 2865 2800 1840 2320 100 2420 Les Deux Alpes 1650 3570 3200 1650 2425 -25 2400 Solden 1380 3055 2700 2000 2350 10 2360 Davos 1560 2845 2650 1850 2250 100 2350 La Plagne 2000 3250 2500 2000 2250 0 2250 Courchevel 1850 2950 2650 1850 2250 0 2250 Alpe d'Huez 1850 3330 2700 1850 2275 -25 2250 Les Arcs 1600 3225 2600 1800 2200 0 2200 Zurs 1720 2450 2450 1720 2085 100 2185 Meribel 1600 3200 2650 1700 2175 0 2175 Flims 1100 2980 2550 1600 2075 100 2175 Wengen 1270 2490 2400 1800 2100 50 2150 Obertauern 1740 2315 2200 1700 1950 200 2150 St Anton 1300 2650 2350 1700 2025 100 2125 Montgenevre 1850 2600 2450 1850 2150 -25 2125 Chamonix 1040 3790 2450 1800 2125 0 2125 Isola 2000 2000 2610 2400 1850 2125 -50 2075 Courmayeur 1230 3450 2350 1700 2025 0 2025 Selva 1550 2680 2150 1550 1850 150 2000 Serre Chevalier 1400 2780 2500 1500 2000 -25 1975 Lech 1450 2370 2300 1450 1875 100 1975 Flaine 1600 2480 2350 1600 1975 0 1975 Avoriaz 1800 2275 2200 1600 1900 0 1900 La Clusaz 1100 2490 2490 1300 1895 0 1895 Badgastein 1080 2685 2200 850 1525 200 1725 Saalbach 1000 2095 2000 1000 1500 200 1700 Megeve 1100 2350 2000 1300 1650 0 1650 Kitzbuhel 760 2000 1950 750 1350 200 1550 Schladming 750 2015 1900 750 1325 200 1525 ---------------------------------------------------------------------- Copyright: The Independent ----------------------------------------------------------------------

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