ChapterPDF Available

Climate change and snow cover in the European Alps


Abstract and Figures

Climatic changes are already having a significant impact on snow cover in the European Alps. Several studies from Switzerland, France, Austria, Italy and Germany have noted a general decrease in snow depth and snow cover duration since the end of the 1980s throughout the European Alps. Investigations of snow cover and climate change have revealed that the reduction in snow reliability observed in low and medium altitude ski resorts is mainly caused by warmer winter temperatures. Precipitation becomes the determining factor for a snowy winter only above 2000 m asl. Projected changes in temperature and precipitation are expected to cause further significant decline in the snowreliability of Alpine ski areas. The impacts of these changes, however, are not uniform. They depend on altitude, region and local factors. For example, the impact of climate change is stronger at low altitudes, in inner-alpine dry valleys and on southern slopes, which leads to winners and losers among the different ski areas. The winter tourism industry has already begun to respond to the implications of these observed changes. A range of technological and behavioural measures have been put into practice to offset the adverse impacts. However, adaptation measures, such as the widespread use of snow-making, put new pressures on the ecology of the mountain environment.
Content may be subject to copyright.
30 The Impacts of Skiing on Mountain Environments, 2013, 30-44
Christian Rixen and Antonio Rolando (Eds)
All rights reserved-© 2013 Bentham Science Publishers
Climate Change and Snow Cover in the European Alps
Christoph Marty*
WSL Institute for Snow and Avalanche Research SLF, Unit Snow and Permafrost,
Flüelastrasse 11, 7260 Davos-Dorf, Switzerland
Abstract: Climatic changes are already having a significant impact on snow cover in
the European Alps. Several studies from Switzerland, France, Austria, Italy and
Germany have noted a general decrease in snow depth and snow cover duration since
the end of the 1980s throughout the European Alps. Investigations of snow cover and
climate change have revealed that the reduction in snow reliability observed in low and
medium altitude ski resorts is mainly caused by warmer winter temperatures.
Precipitation becomes the determining factor for a snowy winter only above 2000 m asl.
Projected changes in temperature and precipitation are expected to cause further
significant decline in the snowreliability of Alpine ski areas. The impacts of these
changes, however, are not uniform. They depend on altitude, region and local factors.
For example, the impact of climate change is stronger at low altitudes, in inner-alpine
dry valleys and on southern slopes, which leads to winners and losers among the
different ski areas. The winter tourism industry has already begun to respond to the
implications of these observed changes. A range of technological and behavioural
measures have been put into practice to offset the adverse impacts. However, adaptation
measures, such as the widespread use of snow-making, put new pressures on the
ecology of the mountain environment.
Keywords: Adaptation measures, precipitation change, snow depth, snow
reliability, temperature change, winter tourism.
Snow influences human life and society in many ways. The amount and duration
of snow in a ski-resort has high socio-economic significance for tourism. Many
mountain towns and villages depend heavily on snow, because their economy is
dominated by winter tourism (by up to 90 %) [1]. The vast majority of customers
of such ski areas live in the pre-alpine regions of Switzerland, Austria, Germany,
*Address correspondence to Christoph Marty: WSL Institute for Snow and Avalanche Research SLF,
Unit Snow and Permafrost, Flüelastr. 11, 7260 Davos Dorf, Switzerland: Tel: ++41 81 4170168; Fax: ++41
81 4170110; E-mail:
Send Orders of Reprints at
Climate Change and Snow Cover
The Impacts of Skiing on Mountain Environments 31
Italy and France. A longer sequence of almost snowless winters in these heavily
populated regions, such as observed between the late 1980s and mid 1990s,
caused problems for some ski areas and initiated a discussion about how
exceptional were such winters. To test for possible connections with climate
change, a number of studies have tried to investigate past variability, and to
predict future trends, for Alpine snow cover.
The financial viability of winter tourism depends to a great extent on favourable snow
conditions and reliable snow in the ski areas. A certain amount of snow is required to
groom the slopes, protect the ground, guarantee safe operation of the slopes, and to
provide the skiers with an enjoyable experience. The minimum snow depth from an
operational point of view, which may differ from the skiers’ perspective, depends on
the nature of the slopes. In general, a snow depth of 30 cm is considered sufficient, 50
cm good, and 70 cm excellent [2]. However, rocky slopes at higher elevations may
require much greater snow depths to be skiable (up to 1 m).
To investigate the impact of climate change on winter tourism in the Alps, it is
therefore important to understand the notion of natural snow reliability. Various
criteria have been proposed in the literature to assess the natural snow reliability of
ski areas. The so-called 100-day rule, first suggested by Witmer [2] is the most
widely accepted definition. According to this rule, there is natural snow reliability if
it is possible to successfully operate a ski area with sufficient snow cover for skiing
for at least 100 days during 7 out of 10 seasons [3]. However, there is no generally
applicable minimum snow depth to operate slopes, as this depends on the
characteristics of the resort and slopes, e.g., rockiness or north–south orientation.
In the Swiss Alps, Laternser and Schneebeli [4] found that the criteria for the 100-
day rule with a 30 cm threshold for snow depth, are currently fulfilled by areas at
altitudes above about 1300 m asl. This suggests that one of the conditions required
to run a successful ski business under current climate conditions in Switzerland is a
minimum elevation of about 1300 m asl, which is assumed to be the line of natural
snow-reliability (Fig. (1)). But this line varies across the Alpine is due to the
considerable variation in Alpine climate. Colder regions will have natural snow-
reliability at lower altitudes than warmer regions. Wielke et al. [5]
32 The Impacts of Skiing on Mountain Environments Christoph Marty
Figure 1: Probability of good, medium and bad winters for a ski area in the eastern Swiss Alps
with a mean altitude at 1200 m asl for past (1958-2007) and future (2030) conditions. The 100-day
rule can only be fulfilled with the 20 cm threshold for past winters (violet) and 10 cm threshold for
future winters (brown). The red numbers show the percentage change between past and future
winters (1 December - 15 April).
compared snow cover duration in the Alps and found the patterns in Switzerland
and Austria were similar, but comparable features were located about 150 m
higher in Switzerland than in eastern Austria. This indicates a transition from an
Atlantic-maritime to a more continental climate, with colder winters in the more
eastern parts of the Alps. The baseline of natural snow-reliability as established in
Switzerland is therefore probably 150 m lower (i.e. at 1050 m asl) in eastern
0>0 >10 >20 >30 >40 >50
Snow depth > x [cm]
Relative Frequency [%]
-19 -16
-10 -9
10 7
5-1 -4 -4
9 9 913 13
>= 100 days (good winter)
40 =< days < 100 (medium winter)
< 40 days (bad winter)
Climate Change and Snow Cover
The Impacts of Skiing on Mountain Environments 33
Austria. On the other hand, Marty [6] showed that the ski resorts above 1300 m
asl on the southern side of the Swiss Alps experience about 20 % fewer snow
days, i.e. days with at least 50 cm of snow, than the ski resorts on the northern
side of the Alps. This indicates that the line of natural snow-reliability for ski
areas influenced by a warmer Mediterranean climate is lower than that for the
northern parts of the Alps.
Some Alpine countries have a relatively dense network of measurement stations,
where daily snow depth and snowfall have been measured with the help of a
permanently mounted snow stake and a new snow board for 50 years or more.
The availability of this comprehensive dataset, as well as the socio-economic
importance of snow in Alpine countries, make the Alps a preferred region to
investigate changes in snow cover. The measurement locations are not always in
ski resorts, but are often close by or at similar altitudes and regions. Remote-
sensing data for Alpine snow cover have not yet been used for climatological
purposes due to the lack of longer time series and the limited data quality arising
from the steep topography of the Alps.
This chapter provides an assessment of the impacts of climate change on snow cover
(snow reliability) on ski areas in the European Alps. I present: 1) an overview of
observed snow cover changes in the different Alpine countries, 2) the results of
climate change scenarios for future snow cover, and finally 3) some adaptation
strategies adopted by ski area managers. The implications of this assessment,
however, extend beyond the European Alps. Insights into adaptation strategies, for
example, are also likely to be relevant for other mountain regions facing similar
climatic changes, such as North America, Australia and New Zealand.
The seasonal snow cover in the Alps is primarily influenced by high year-to-year
variability due to anomalies in large-scale weather patterns [7]. Several studies have
nevertheless noted a general decrease in snow depth and snow cover duration since
the end of the 1980s at low-lying stations throughout the European Alps.
In the Swiss Alps, a significant decrease in snow depth for elevations below 1300 m
asl was observed in the late 20th century with measurements from more than 100
34 The Impacts of Skiing on Mountain Environments Christoph Marty
stations [8], whereas no significant differences could be detected for high-altitude
stations above 2000 m asl [30]. The long-term snow trends in the Swiss Alps appear
to be similar for all three variables: snow depth, the duration of continuous snow
cover and the number of snow fall days [4]. Earlier investigations concluded that the
length of the snow season and the amount of snow have substantially decreased
since the mid 1980s, but during several periods in the records, e.g., in the 1930s, the
snow depth was as low as during the late 1980s [9]. However, a newer study using
more data from the last 130 years indicated that the series of snow-poor winters over
the 20-year period from 1988 to 2007 was unique [6]. In particular, it showed that
the decline was caused by an abrupt change, rather than by a continuous decrease
(Fig. (2)). The number of snow days, i.e. days with snow depth of at least 30 cm, at
ski resorts between 800 and 1200 m asl, for example, dropped by about 35 % after
the end of the 1980s compared to the long-term mean before the change. The
determining signal for this change was mainly temperature and not precipitation [6,
8], and this has had considerable impact on the mean evolution of snow cover during
the last twenty years (Fig. (3)).
Figure 2: Number of snow days, i.e. days with at least 30 cm snow on the ground (with exception
of Innsbruck (20 cm) and Col de Porte (50 cm)), at ski resorts in 6 Alpine countries. All stations
show a striking shift towards significantly less snow in the last 20 years. The values are based on
10-year low-pass filtered values of annual snow days between December and March.
In the Austrian Alps, various snow parameters at 98 long-term stations were
investigated and a more diverse picture was found [10]. The two 20-year periods
Snow Days
Col de Porte, FR 1325m
Engelberg, CH 1060m
Hohenpeissenberg, DE 977m
Auronzo, IT 864m
Kranjska Gora, SLO 812m
Innsbruck, AT 577m
Climate Change and Snow Cover
The Impacts of Skiing on Mountain Environments 35
between 1980 and 2000 and between 1896 and 1916 were compared and tested
for changes. Statistical tests detected decreasing trends at the majority of the
stations, but the decline was only significant at the southern Austrian stations.
There, a clearly decreasing trend was found for the duration of winter snow cover
and the days with snow depths of more than 1 cm. A separate analysis of 14
stations with 100 years of data revealed similar results with snow day trends in
southern Austria mostly significantly decreasing and no significant trends in the
remaining parts of the country.
Figure 3: The less snowy winters during the last 20 years result in a clear reduction of the snow
depth during the winter season, as shown here for the ski resort of Engelberg in the Swiss Alps.
Note that the spring snow cover seems to be more affected than early-winter snow cover.
In the Italian Alps, a general decrease in snow depth and snow duration during the
last twenty years was found in the analyzed time series between 1920 and 2009
using data from 30 stations [11]. The authors relate this decrease to reduced snow
fall, which in turn may be caused by a higher ratio of liquid precipitation due to
warmer winter temperatures as recently demonstrated [31]. The spring reduction
in snow depth was not as unique as the reduction over the whole winter.
Surprisingly, these results were confirmed by 20 stations situated between 2000
and 3000 m asl in a small area in northern Italy [12]. In the German Alps, a 20-30
Snow Depth (cm)
Engelberg, 1060 m a.s.l.
20 Years
1989 - 2008
80 Years
1909 - 1988
Oct Nov Dec Jan Feb Mar Apr May
Averaged Daily Values
Running Mean
36 The Impacts of Skiing on Mountain Environments Christoph Marty
% reduction in snow cover duration was found for low-lying areas between 1952
and 1996 [13]. A smaller reduction of about 10 % was observed in higher areas.
In the French Alps, snow trends between 1958 and 2005 were investigated with
the help of an automatic system that combined three numerical models to simulate
meteorological parameters and snow stratigraphy [14]. As input data, the system
was fed with meteorological observations and 40 years re-analysis data (ERA-40)
from the European Centre for Medium-range Weather Forecasts (ECMWF). The
few available long-term snow observations were finally used for verification. The
results demonstrate a significant decrease in snow depth at low and mid altitudes,
but this signal is weaker in the south than in the north and less visible at high
elevations. Concerning snow duration, a shift in the mean values at the end of the
1980s confirmed the finding reported in Marty [6]. The results have also been
interpreted in terms their implications for a viable ski industry. French downhill
ski resorts are currently economically viable above elevations ranging from about
1200 m asl in the northern foothills to 2000 m in the south.
Climate models today can successfully reproduce large-scale parameters such as
temperature. However, investigations on the evolution of the future snow pack
under changing climate conditions all battle with the fact that the current climate
models have difficulties in representing the fine-scaled spatial and temporal
variability of snow. Some studies therefore use physical models driven by
artificially generated data of future weather conditions to predict the snow depth
and duration at local levels. Other studies estimate future snow conditions based
on a sensitivity analysis of the current variability.
For example, Hantel and Hirtl-Wielke [15] assessed the snow-temperature
sensitivity in the European Alps based on data recorded during the past 40 years
at 268 stations and came to the conclusion that the number of snow days (days
with snow depths greater than 5cm) will decrease by 33% per 1°C increase in
temperature. This corresponds to a reduction of snow cover duration of about 1
month at the altitude of maximum sensitivity (about 700 m asl), but falls rapidly
above and below that level. The future snow reliability of 666 Alpine ski resorts
in 6 European countries was investigated by Abegg et al. [16]. They calculated
Climate Change and Snow Cover
The Impacts of Skiing on Mountain Environments 37
the impact of temperature increases of 1°C, 2°C and 4°C based on the assumption
that the altitudinal limit of natural snow-reliability will rise by 150 m per 1°C
warming. They concluded that the number of naturally snow-reliable areas would
drop by 25% with a temperature increase of 1°C, by 40% with 2°C, and by 70 %
with a 4°C warming (Fig. (4)).
Figure 4: Number of naturally snow-reliable ski areas in the European Alps under present and
future climate conditions. Regions with low-altitude ski areas, for example in southern Germany,
are most affected by future warming (Adapted from Abegg et al. [16]).
Future Austrian snow conditions were analyzed using a simple temperature- and
precipitation-dependent snow model by Breiling and Charamza [17]. They
concluded that the impact of 2°C warming would mean only a few locations at
higher altitudes would be suitable for winter tourism and skiing. None of these
studies [15-17] took into account the local influences of topography or orientation
at each location, and they assumed that the current sensitivity of the snow cover
will not change in the future.
The other approach of coupling existing snow-cover models with meteorological
input data from regional climate models (RCMs) for future climate scenarios was
38 The Impacts of Skiing on Mountain Environments Christoph Marty
first applied by Beniston et al. [18] in the Swiss Alps. Using a single-layer snow-
cover model and assuming a 4°C temperature increase by the end of this century,
they found a 50 % reduction in snow volume with a termination of the season
about 50 days earlier at 2000 m asl. For the French Alps, Martin and Etchevers
[19] used future temperature fields from a GCM as input for their multi-layer
snow-cover model. They found a 50 % reduction in snow depth below 1500 m asl
and 30 % smaller snow covered area in mid-winter with a 1.8 °C temperature
increase, when precipitation was kept constant. They concluded that changes of
this magnitude could have a major impact on the skiing industry in the French
Alps, especially at lower elevations. The length of the skiing season could
decrease substantially and ski areas may increasingly move into less temperature-
sensitive high-elevation areas.
The sensitivity of snow cover to future climate has recently been analyzed at 20
ski resorts in the Swiss Alps using a more sophisticated approach [20]. With a
well-elaborated perturbation method and RCM model data as input for their single
layer snow cover model, the researchers computed snow reliability at the end of
this century with a predicted 4° C increase in temperature. With this scenario,
snow will become scarce on the lower ski runs in all resorts and days when the
snow depth is more than the critical 30 cm snow depth will drastically decrease at
more than half of the stations. In addition, at the critical altitude, i.e. the altitude
above which snow is required for the ski lifts to run, more than half of the
stations, on average, will have snow depths below the critical 30-cm level.
Hydrological studies that investigate the impact of climate change on snow cover
as a water resource can often also be used for the analysis of snow reliability of
ski resorts, which are situated within water catchments. Potential future changes
in two such Alpine river basins (above 800 m asl) in the Swiss Alps have been
investigated with the help of the distributed catchment model WaSiM-ETH [21].
According to 23 regional climate models, 2.5°C warming and small changes in
precipitation can be expected by the end of the 21st century. The model predicted
a decrease of 70 % in the annual mean snow-water equivalent, two months less
continuous snow cover and a snowline rise of 450 m. Bavay et al. [22] and
Magnusson et al. [23] focused on three other alpine river basins (above 1600 m
asl) using the spatially distributed model system Alpine3D and the IPCC A2 and
Climate Change and Snow Cover
The Impacts of Skiing on Mountain Environments 39
B2 scenarios output from 6 RCMs. Their results indicated that the snow volume
and the maximum snow water equivalent at the end of the 21st century are likely
to be reduced by about 40%. The complete melt of the snow cover will occur
about 40 days earlier and the snow line will be shifted by about 900 m, which
would mean most of the glaciers in these basins would disappear and limit the
natural snow reliability to altitudes above 2000 m asl.
Managers of ski areas and stakeholders in tourism are not just waiting to see what
the consequences of climate change are, but have already begun to prepare for less
snowy winters [3, 24-26]. They realize that the ski industry is highly dependent on
snow conditions and that snow-deficient winters pose a risk. Adaptation practices
found among ski area operators can be divided into two main categories:
technological and behavioral [16].
Technological adaptations appear so far to be the adaptation strategies most
favored by tourism stakeholders in the European Alps. The three main types are
listed here in order of priority. Their impacts on the mountain environment are
discussed in detail in the other chapters:
Landscaping: This strategy involves the landscaping of large ski areas
(e.g., machine-grading or bulldozing of ski runs, creation of shaded
areas) and the contouring or smoothing of smaller areas (e.g., the
leveling of rough and bumpy surfaces, and the removal of obstacles
such as rocks and shrub vegetation). The aim is to reduce the snow
depth required for ski operation, which also means a reduction of the
necessary amount of artificial snow.
Artificial snow-making: Snow-making is used to extend the operating
season and to increase the range of climate variability and climate
change with which a ski area can cope. While artificial snow-making
was initially viewed as a luxury and then a back up strategy, it now
appears to be viewed as a necessity. According to Pröbstl [27], the
rapid expansion of snow-making in the Alps was triggered by the need
40 The Impacts of Skiing on Mountain Environments Christoph Marty
to secure and guarantee the revenues of the ski area managers and by
the success of the ski resorts that could provide a "snow guarantee".
Going higher and facing north: The aim of this strategy is to
concentrate ski operations in locations with a climatic advantage. The
different options for this strategy include: moving operations to the
upper part of an existing ski area or building new ski areas on north-
facing slopes, at higher elevations and possibly on glaciers.
Behavioral adaptations range from new business models and new financial tools
to a change in operational practices and a move towards the diversification of
Mergers and corporations: A very common form of cooperation is the
merger of different companies in one valley or even from neighboring
valleys with the aim of reducing marketing and operational costs. Another
form of cooperation is the regional association, which offers one ski pass
for several ski areas. A less well-known form of cooperation is the
collaboration between a small low-altitude, but close-to-the-city, ski area
and a large mountain ski area to "nurse" future customers and to have a
marketing platform close to heavily populated regions.
Financial support: A growing number of ski area managers consider
snow-making to be a public service and therefore claim that all those who
benefit should contribute to the costs. The options go from sharing the
cost of snow-making with the accommodation sector to governmental
subsidies for the ski area. Local authorities can, for example, make one-
off or annual contributions, issue loans or take a share in the business.
This is highly beneficial for a ski resort as the local authorities generally
receive better financial ratings than ski area managers.
Diversification: Many resorts have made substantial investments to
cater for the growing market of non-skiers. The most popular
activities are winter hiking, tobogganing and snowshoeing. The
problem, of course, with these non-ski related activities is that they
Climate Change and Snow Cover
The Impacts of Skiing on Mountain Environments 41
also require snow, although less than for downhill skiing. Moreover,
these new activities, which often take place in previously undisturbed
surroundings, may cause new problems for some animals already
struggling to cope with the harsh winter environment.
However, these strategies cannot all be causally linked only to climate change, as
trends in tourism, prestige, and competitive advantage are also important factors.
Figure 5: Snow as a resource: Artificial snow from the previous winter is preserved during
summer under a thick layer of woodchips at 1600 m asl in Davos, Switzerland. In the early winter
of the same year, this pile of snow will help to produce a cross-country ski track. Such
management of snow supplies and snow reserves is called snow farming. Snow farming is
nowadays practiced by many ski resorts in order to keep the slopes well-stocked with snow to
attract visitors (Photo: SLF).
The seasonal snow cover in the Alps is primarily influenced by a high year-to-
year variability due to large-scale weather patterns. Despite this variability, a
general decrease in snow depth and snow cover duration has been apparent since
the end of the 1980s at low-lying stations throughout the European Alps. The
42 The Impacts of Skiing on Mountain Environments Christoph Marty
decline could be linked to the anomalously warm winter temperatures during the
last twenty years [6, 8], which seem to be unique over at least the last 500 years
[28]. During the past 100 years in Switzerland, for example, the observed
warming has been roughly twice as high as the global average [29].
The development of winter tourism and skiing infrastructure in the European Alps
during the past 30 years has tended to follow the decadal temperature variations.
The period 1965-1985, when an expansion of ski areas occurred, was a relatively
cold one. The period 1985-1995, was considerably warmer, and most winter
resorts had snow problems during this time, many of them serious, and artificial
snow making became popular. A rise of just 0.8 °C in temperature necessitated
considerable adaptation, which is still required today.
Research on future snow cover has taken two different approaches, one based on
physical models and the other based on current snow-temperature sensitivity.
Assuming 2°C warming, both came to similar results: Snow depth will drastically
decrease by about 40-60% below 1800 m; the snow cover will last 4 to 6 weeks
less and the snow line will rise by about 300-500 m. According to the RCM
projections, the warming in the Alps will be accompanied by a small increase in
winter precipitation. Some authors therefore concluded that, at higher altitudes,
where the temperatures are still cold enough for substantial snowfall, the snow
depth may even increase with climate warming. However, the outcomes of two
recent studies imply that the projected increase in winter precipitation over the
Alps will not compensate for the projected increase in temperature even at the
higher resorts [20, 22].
These projected changes in temperature and precipitation will most certainly be a
challenge for the winter tourism sector. Since the Alpine snow cover is very
sensitive to temperature, the depth, length and duration of the snow cover is
greatly influenced by climate change. As warming progresses in future, regions
where snowfall is the current norm will increasingly experience rain, and the
snow on the ground will melt faster. To mitigate the effects of this process,
innovative technical solutions and behavioral adaptations are needed to conserve
energy and to ensure the mountain environment is harmed as little as possible.
Sophisticated storage methods, (see Fig. (5)), or improved artificial snow
Climate Change and Snow Cover
The Impacts of Skiing on Mountain Environments 43
production may help to safeguard winter tourism in regions where few other
economic resources are available. Future perspectives leave no doubt, however,
that the projected climate changes will have considerable impact on the economic,
social, hydrological and biological systems in the Alpine region.
The author confirms that this article content has no conflict of interest.
The author gratefully acknowledges data from Meteoswiss, DWD, Meteo France,
Arpa Veneto, Regione Autonoma Valle d'Aosta, Environmental Agency of the
Republic of Slovenia, University of Innsbruck and the European Climate
Assessment & Dataset project.
[1] Elsasser, H. and P. Messerli, The Vulnerability of the Snow Industry in the Swiss Alps.
Mountain Research and Development, 2001. 21: p. 335-339.
[2] Witmer, U., Erfassung, Bearbeitung und Kartierung von Schneedaten in der Schweiz.
Geographica Bernesia. Vol. G25. 1986: Geographisches Institut der Universität Bern.
[3] Bürki, R., et al., Climate change and tourism in the Swiss Alps., in In Aspects of Tourism.
Tourism, recreation and climate change, C.M. Hall and J. Higham, Editors. 2005. p. 155-163.
[4] Laternser, M. and M. Schneebeli, Long-term snow climate trends of the Swiss Alps (1931-
99). International Journal of Climatology, 2003. 23(7): p. 733-750.
[5] Wielke, L.-M., L. Haimberger, and M. Hantel, Snow cover duration in Switzerland
compared to Austria. Meteorologische Zeitschrift, 2004. 13: p. 13-17.
[6] Marty, C., Regime shift of snow days in Switzerland. Geophys. Res. Lett., 2008. 35.
[7] Scherrer, S.C. and C. Appenzeller, Swiss Alpine snow pack variability: major patterns and
links to local climate and large-scale flow. Climate Research, 2006. 32(3): p. 187-199.
[8] Scherrer, S.C., C. Appenzeller, and M. Laternser, Trends in Swiss Alpine snow days: The
role of local- and large-scale climate variability. Geophys. Res. Lett., 2004. 31.
[9] Beniston, M., Variatons of snow depth and duration in the Swiss Alps over the last 50 years:
Links to changes in large-scale climatic forcings. Climatic Change, 1997. 36: p. 281-300.
[10] Jurkovic, A., Gesamtschneehöhe - Vergleichende Zeitreihenanalyse, in Meteorology. 2008,
University of Vienna: Vienna.
[11] Valt, M. and P. Cianfarra, Recent snow cover variation and avalanche activity in the
Southern Alps. Cold Regions Science and Technology, 2010. 64(2): 146-157.
[12] Bocchiola, D. and G. Diolaiuti, Evidence of climate change within the Adamello Glacier of
Italy. Theoretical and Applied Climatology, 2009.
[13] Günther, T., M. Rachner, and H. Matthäus, Langzeitverhalten der Schneedecke in Baden-
Württemberg und Bayern. KLIWA-Projekt A 1.1.4: "Flächendeckende Analyse des
44 The Impacts of Skiing on Mountain Environments Christoph Marty
Langzeitverhaltens verschiedener Schneedeckenparameter in Baden-Württemberg und
Bayern., in KLIWA Berichte, A. KLIWA, Editor. 2006. p. 76.
[14] Durand, Y., et al., Reanalysis of 47 Years of Climate in the French Alps (1958-2005):
Climatology and Trends for Snow Cover. Journal of Applied Meteorology and
Climatology, 2009. 48(12): p. 2487-2512.
[15] Hantel, M. and L.-M. Hirtl-Wielke, Sensitivity of Alpine snow cover to European
temperature. International Journal of Climatology, 2007. 27(10): p. 1265-1275.
[16] Abegg, B., et al., Climate change impacts and adaptation in winter tourism, in Climate
Change in the European Alps, S. Agrawala, Editor. 2007, OECD: Paris. p. 25-60.
[17] Breiling, M. and P. Charamza, The impact of global warming on winter tourism and skiing:
a regionalised model for Austrian snow conditions. Regional Environmental Change, 1999.
1(1): p. 4-14.
[18] Beniston, M., et al., Estimates of snow accumulation and volume in the Swiss Alps under
changing climatic conditions. Theoretical and Applied Climatology, 2003. 76(3): p. 125-140.
[19] Martin, E. and P. Etchevers, Impact of climatic changes on snow cover and snow
hydrology in the French Alps, in Global Change and Mountain Regions: An Overview of
Current Knowledge, U.M. Huber, H.K.M. Bugmann, and M.A. Reasoner, Editors. 2005,
Springer. p. 235-242.
[20] Uhlmann, B., S. Goyette, and M. Beniston, Sensitivity analysis of snow patterns in Swiss
ski resorts to shifts in temperature, precipitation and humidity under conditions of climate
change. International Journal of Climatology, 2008.
[21] Jasper, K., et al., Differential impacts of climate change on the hydrology of two alpine
river basins. Climate Research, 2004. 26(2): p. 113-129.
[22] Bavay, M., et al., Simulations of future snow cover and discharge in Alpine headwater
catchments. Hydrological Processes, 2009. 23(1): p. 95-108.
[23] Magnusson, J., et al., Snow cover response to climate change in high alpine and half
glaciated basin in Switzerland. Hydrology Research, 2010. 41(3-4): 230-240.
[24] Wolfsegger, C., S. ssling, and D. Scott, Climate Change Risk Appraisal in the Austrian Ski
Industry. Tourism Review International, 2008. 12: p. 13-23.
[25] Steiger, R. and M. Mayer, Snowmaking and climate change. Mountain Research and
Development, 2008. 28(3/4): p. 292-298.
[26] Hoffmann, V.H., et al., Determinants of corporate adaptation to climate change in winter
tourism: An econometric analysis. Global Environmental Change, 2009. 19(2): p. 256-264.
[27] Pröbstl, U., Kunstschnee und Umwelt - Entwicklung und Auswirkungen der technischen
Beschneiung. 2006, Bern: Haupt Verlag 232
[28] Luterbacher, J.r., et al., Exceptional European warmth of autumn 2006 and winter 2007:
Historical context, the underlying dynamics, and its phenological impacts. Geophys. Res. Lett.,
2007. 34.
[29] Rebetez, M. and M. Reinhard, Monthly air temperature trends in Switzerland 1901–2000
and 1975–2004. Theoretical and Applied Climatology, 2008. 91(1): p. 27-34.
[30] Marty, C. and Meister, R., 2012: Long-term snow and weather observations at
Weissfluhjoch and its relation to other high-altitude observatories in the Alps. Theoretical
and Applied Climatology:1-11. doi:10.1007/s00704-012-0584-3.
[31] Serquet, G., Marty, C., Rebetez, M. and Dulex, J.P., 2011: Seasonal trends and temperature
dependence of the snowfall/precipitation day ratio in Switzerland, Geophysical Research
Letters, 38, L07703, doi:10.1029/2011GL046976.
... Snow cover phenology further modulates habitat interactions of several plant and animal species [6][7][8], and changes in the seasonality of snow cover in high mountain ecosystems might put the survival of some species at risk [9,10]. In the European Alps, meltwater from snow cover makes up a consistent share of runoff used for hydropower generation [11,12]; snow also plays a vital role for the economy of the Alpine region by supporting winter tourism through skiing and other winter sports [4,13]. These activities are, in fact, dependent on the snow depth and distribution, and they are severely affected by the current climate change, which can lead 2 of 26 to a reduction in snow cover as the increasing air temperature leads to more precipitation falling as rain and earlier snowmelt in the spring [14]. ...
... Across the Alps, changes in the duration, onset and melt-out dates of snow cover have already been observed at several locations from in-situ weather station records: Valt and Cianfarra [17] reported a decrease in winter and spring snow cover durations since the 1950s at a rate between 0.4 and 5 days per decade from stations located in the eastern and western Italian Alps, while Bocchiola and Diolaiuti [18] observed negative trends in the snow depth starting in the 1990s from a record of 40 stations located in the Adamello region. In the French Alps, a decrease in the average snow depth of −39 cm between 1960 and 1990 and 1990 and 2017 was reported by Lejeune et al. [19] at Col de Porte (1325 m a.s.l.); in Switzerland, a step like decrease in snow days between 20% and 60% since the end of the 1980s was observed by Marty [20], while in Austria, a decrease in the winter snow cover duration between 1980 and 2000 compared to was found significant at stations in the southern region of the country [13]. The negative trend in Alpine snow cover duration was further confirmed by Matiu et al. [21] on the basis of an analysis of more than 800 station records from 1971 to the present. ...
... While ground stations are able to provide snow cover observations up to the 1950s, or even to the 1900s [13], the data are sparse, often incomplete and representative only of a small area around the point of measurement, which can affect the assessment of long term trends and lead to issues if the snow cover data are to be used for the estimation of runoff and for projecting future changes in the freshwater availability of river systems [22]. Satellite records are thus often used to complement or substitute in-situ observations: the snow cover duration in the Northern hemisphere since 1967 is, for instance, available from a combination of satellites through the NOAA (National Oceanic and Atmospheric Administration) snow cover extent climate data record; however, the coarse resolution of this product (approximately 200 km) and its binary snow grid make it difficult to observe trends in mountain regions [3]. ...
Full-text available
Snow cover is particularly important in the Alps for tourism and the production of hydroelectric energy. In this study, we investigate the spatiotemporal variability in three snow cover metrics, i.e., the length of season (LOS), start of season (SOS) and end of season (EOS), obtained by gap-filling of MOD10A1 and MYD10A1, daily snow cover products of MODIS (Moderate-resolution Imaging Spectroradiometer). We analyze the period 2000–2019, evaluate snow cover patterns in the greater Alpine region (GAR) as a whole and further subdivide it into four subregions based on geographical and climate divides to investigate the drivers of local variability. We found differences both in space and time, with the northeastern region having generally the highest LOS (74 ± 4 days), compared to the southern regions, which exhibit a much shorter snow duration (48/49 ± 2 days). Spatially, the variability in LOS and the other metrics is clearly related to elevation (r2 = 0.85 for the LOS), while other topographic (slope, aspect and shading) and geographic variables (latitude and longitude) play a less important role at the MODIS scale. A high interannual variability was also observed from 2000 to 2019, as the average LOS in the GAR ranged between 41 and 85 days. As a result of high variability, no significant trends in snow cover metrics were seen over the GAR when considering all grid cells. Considering 500-m elevation bands and subregions, as well as individual grid points, we observed significant negative trends above 3000 m a.s.l., with an average of −17 days per decade. While some trends appeared to be caused by glacierized areas, removing grid cells covered by glaciers leads to an even higher frequency of grid cells with significant trends above 3000 m a.s.l., reaching 100% at 4000 m a.s.l. Trends are however to be considered with caution because of the limited length of the observation period.
... The general decrease in snow depth and snow cover duration since the end of the 1980s throughout the European Alps poses a great challenge for winter tourism in ski resorts at low and medium altitudes, and the winter tourism industry has already begun to respond to the implications of these changes (König, 1999;Abegg, 2011;Marty, 2013). Current technical solutions, such as snow-making, grooming and snowfarming (the storage and conservation of snow, generally during the warm season of the year, for use in the subsequent winter season), are adaptive strategies to face this snow deficit, but they have their limitations. ...
Full-text available
Snow-farming is one of the adaptive strategies used to face the snow deficit in ski resorts. We studied the impact of a shifting snow-farming technique on a pasture slope in Adelboden, Switzerland. Specifically, we compared plots covered by a compressed snow pile for 1.5, 2.5 or 3.5 years, which then recovered from the snow cover for three, two or one vegetation seasons, respectively, with control plots situated around the snow pile. In plots with >1.5 years of compressed snow pile, plant mortality was high, recovery of vegetation was very slow, and few plant species recolonized the bare surface. Soil biological activity decreased persistently under prolonged snow cover, as indicated by reduced soil respiration. The prolonged absence of fresh plant litter and root exudates led to carbon (C) limitation for soil microbial respiration, which resulted in a significant decrease in the ratio of total organic carbon to total nitrogen (TOC/TN) under the snow pile. Microbial C, nitrogen (N) and phosphorus (P) immobilization decreased, while dissolved N concentration increased with compressed snow cover. Longer snow cover and a subsequent shorter recovery period led to higher microbial C/P and N/P but lower microbial C/N. Nitrate and ammonium were released massively once the biological activity resumed after snow clearance and soil aeration. The soil microbial community composition persistently shifted towards oxygen-limited microbes with prolonged compressed snow cover. This shift reflected declines in the abundance of sensitive microorganisms, such as plant-associated symbionts, due to plant mortality or root die-off. In parallel, resistant taxa that benefit from environmental changes increased, including facultative anaerobic bacteria (Bacteroidota, Chloroflexota), obligate anaerobes (Euryarchaeota), and saprophytic plant degraders. We recommend keeping snow piles in the same spot year after year to minimize the area of the impacted soil surface and plan from the beginning soil and ecosystem restoration measures.
... Trichinella britovi larvae survive longer in carcasses beneath than in those above the snow (Pozio, 2022). During the past 60 years, there has been a significant reduction in T. britovi prevalence in red foxes from Alpine regions (Pozio, 2022) of between 20 and 30% (Marazza, 1960;Rossi et al., 2019) which correlates with a significant decrease in snow depth and snow cover in the Alps (Scherrer et al., 2004;Marty, 2013). ...
Full-text available
Helminth zoonoses remain a global problem to public health and the economy of many countries. Polymerase chain reaction-based techniques and sequencing have resolved many taxonomic issues and are now essential to understanding the epidemiology of helminth zoonotic infections and the ecology of the causative agents. This is clearly demonstrated from research on Echinococcus (echinococcosis) and Trichinella (trichinosis). Unfortunately, a variety of anthropogenic factors are worsening the problems caused by helminth zoonoses. These include cultural factors, urbanization and climate change. Wildlife plays an increasingly important role in the maintenance of many helminth zoonoses making surveillance and control increasingly difficult. The emergence or re-emergence of helminth zoonoses such as Ancylostoma ceylanicum, Toxocara, Dracunculus and Thelazia exacerbate an already discouraging scenario compounding the control of a group of long neglected diseases.
... To carry out this study, the following methodological steps were followed: -consultation of works related to the area of the Bârgău Mountains (Bîca, 2012;Naum, Butnaru, 1984;Rusu, 1998); -consulting snowology and the impact of climate change on tourism and sports (Beniston, 1997;Bigano et al., 2005;Brugnot, 2017;Elsasser, Messerli, 2001;Fang et al., 2021;Gonseth, 2013;Hallmann et al. al., 2012;Hammond et al., 2018;Martin et al., 2021;Marty, 2013;Moen, Fredman, 2007;Neuvonen, Sievänen, Fronzek, 2015;Nicholls, 2006;Petrović, 2013;Pütz, Gallati, Kytzia, 2011;Rixen et al., 2011;Roussillon-Nadal, 2014;Scott, McBoyle, 2007;Scott, Dawson, Jones, 2008;Steiger, Scott, Abegg, 2019;Weaver, 2011;Zeng et al., 2018); -performing nivological observations in the period 2018-2022, which aimed at the distribution, thickness, duration, and stability of the snow layer, the stratigraphy of snow deposits, metamorphic transformations of snow, as well as the quality of snow deposits to capitalize on them in sports activities and leisure; -a collection of meteorological data from the automatic stations installed in the localities of Piatra Fântânele, Lunca Ilvei, and Prundu Bârgăului for the period December 2021-February 2022; ...
Full-text available
The Bârgău Mountains are located in the northern group of the Eastern Carpathians and represent a territory with a vocation for practicing winter sports (especially cross-country skiing), but also for sports leisure (hiking, cross-country skiing, freeride). This is due to the snow potential of the mountainous area, especially above 1000 m, where the specific phenomena of winter favor the deposition of a thick layer of snow, which, however, fluctuates in duration and thickness depending on climatic variations affecting the region. The analysis of the snow potential was based on the observations made during 2018-2022, on winter phenomena and snow deposits, and the data obtained were correlated with the morphometric characteristics of the relief, finally establishing the optimal areas for certain sports and leisure activities. Received 2022 June 16; Revised 2022 June 30; Accepted 2022 July 04; Available online 2022 June 30; Available print 2022 August 30. REZUMAT. Potențialul nivologic al Munților Bârgău, cu relevanță pentru practicarea sporturilor de iarnă și a activităților recreative. Munții Bârgăului sunt situați în grupa nordică a Carpaților Orientali și reprezintă un teritoriu cu vocație pentru practicarea sporturilor de iarnă (în special a schiului fond), dar și a agrementului sportiv (drumeție, schi de tură, freeride). Acest fapt se datorează potențialului nivologic al arealului montan, mai ales peste altitudinea de 1000 m, unde fenomenele specifice iernii favorizează depunerea unui strat consistent de zăpadă, care, totuși, fluctuează ca durată și ca grosime în funcție de variațiile climatice care afectează regiunea. Analiza potențialului nivologic s-a bazat pe observațiile efectuate în perioada, 2018-2022, asupra fenomenelor de iarnă și asupra depozitelor de zăpadă, iar datele obținute au fost corelate cu caracteristicile morfometrice ale reliefului, în final stabilindu-se suprafețele optime pentru anumite activități sportive și agrementale. Cuvinte cheie: cuvertură de zăpadă, depozit de zăpadă, strat fiabil de zăpadă, secțiune prin zăpadă, profil stratigrafic, sporturi de iarnă, agrement de iarnă, sezon de iarnă, schimbări climatice, bonitarea terenului
... Witmer, Filliger, Kunz, and Kung [25], cited by Abegg, Agrawala, Crick, and Montfalcon [26] and Marty [27], referring to the functionality of a ski slope, considered that "a snow depth of 30 cm is considered sufficient, 50 cm good, and 70 cm excellent". In addition, Witmer et al. [25], cited by Yang and Wan [28], stated that only ski areas that are operable at least 100 days per season would be financially viable (so called "100-day rule"). ...
Full-text available
In the last years, Romania has made major efforts to develop the skiing areas and some important projects have been implemented in the Carpathian Mountains. This research highlights the low efficiency of ski slopes and ski areas concerning the functionality during the winter season, even though a number of investments have been made. Some examples of bad practices regarding the development of skiing infrastructure in link with the potential impact on the environment are presented. The status of ski slopes, slope conditions, and snow depth were collected daily, during the 2016–2017 and 2017–2018 winter seasons, from a Romanian website specialized in snow cover information. A statistical analysis based on the collected data has been done. The 225 ski slopes studied have been opened, on average, less than 62 days and more than 20% of them have not even been opened. Only 17.8% of the slopes complied with the “100-day rule” during the first season and 21.3% of them during the second one, which does not ensure profitability. In conclusion, too many ski slopes have been created without considering the actual snow conditions. The investors wasted capital that is unprofitable and needlessly, affecting the environmental sustainability.
... Assessments of the impacts of climate change on global mountain systems foresee temperature warming between 1.8 and 4 • C over the European Alps for the period 2051-2080 (Zimmermann et al., 2013). Such temperature increase is associated with a decrease in depth and duration of snow cover in mountain habitats (Marty, 2013;Frei et al., 2018), leading to longer growing seasons and higher frequency of frost events in winter (Gerdol et al., 2013). In response to these changes there are documented upward shifts of tree species within forests (Lenoir et al., 2008), tree-line ecotones (Du et al., 2018) and alpine species above tree line (Parolo and Rossi, 2008;Pauli et al., 2012), which results in plant community thermophilisation and changes in species richness . ...
Full-text available
Mountains and their biota are highly threatened by climate change. An important strategy that alpine plants use to escape this change consists in seed dispersal and the ability of seeds to germinate and establish in new sites at higher elevation. Little is known about the environmental factors that can affect the regeneration of plants above the elevational limit of growth. We present the first field evidence of recruitment success and plant performance in consequence of upward shift from the alpine to the nival life zone. Seeds of four alpine grassland species were sown at the current elevational limit of growth (site A) and 200 m upward, in a nival environment (site N) located in the Italian Alps. At site N part of the seeds were subjected to experimental manipulation of temperature (using an Open Top Chamber, OTC) or soil (using soil from site A). Recruitment success, soil surface temperature and water potential were monitored for five consecutive years. At the end of the experiment, vegetative growth and foliar traits were measured on individuals from all treatments. Mean annual soil surface temperature and length of the growing season at site A were ca. 2°C higher and ca. 44 days longer than at site N. Seedling emergence and seedling establishment generally were higher at N (with or without OTC) on local soil than at site A or at site N with soil originating from site A. Conversely, production was higher at site A and at site N with soil originating from site A. Recruitment success above the elevational leading edge was enhanced by coarser and nutrient-poor soil, which promoted seedling emergence and establishment but constrained plant growth. This trade-off between seedling recruitment and plant production underlines adaptive consequence and environmental filtering, both critical to forecast community assembly and responses of alpine species to climate warming.
Full-text available
Introduction. With the outbreak of the COVID-19 pandemic, caused by the novel coronavirus, major challenges have arisen in terms of the development of the teaching process and sports training. For some of them, the solution was offered by the already existing hardware and software technologies, and this created new educational contexts, as well as opportunities for adaptation and evolution of the teaching and training process. Objectives. Identify in the literature some principles, guidelines, and recommendations regarding the implementation of technology in the educational and training process. Methods. In this paper, the method of studying the literature was used, using information published in international databases. Results. The specialized literature offers many studies on the subject of education assisted by information and communication technology tools, being available examples of success in the specialized practice. Conclusions. The challenges and objectives of current education must be considered in the incorporation of technology into education before deciding how information and communication technology tools can be used to achieve them. The educational context has adapted to the current times, teachers become guides and designers of learning situations where technology is a tool that must be used masterfully by them. Received 2022 May 16; Revised 2022 June 14; Accepted 2022 June 28; Available online 2022 June 30; Available print 2022 August 30. REZUMAT. O privire de ansamblu asupra oportunităților oferite de avansul tehnologiei informației și comunicațiilor în domeniul educației fizice și sportului. Introducere. Odată cu izbucnirea pandemiei de COVID-19, cauzată de noul coronavirus, au apărut provocări majore în privința desfășurării procesului didactic și a antrenamentelor sportive. Pentru o parte dintre acestea, soluția a fost oferită de tehnologiile hardware și software existente deja, iar acest lucru a creat noi contexte educaționale, precum și oportunități de adaptare și evoluție a procesului didactic și de antrenament. Obiective. Identificarea în literatura de specialitate a unor principii, direcții și recomandări în privința implementării tehnologiei în procesul educațional și de antrenament. Metode. În realizarea acestei lucrări s-a folosit metoda studiului literaturii de specialitate, folosind informații publicate în bazele de date internaționale. Rezultate. Literatura de specialitate oferă o cantitate mare de studii pe tema educației asistate de instrumentele tehnologiei informației și a comunicațiilor, fiind disponibile exemple de succes din practica de specialitate. Concluzii. În încorporarea tehnologiei în educație trebuie avute în vedere provocările și obiectivele educației curente înainte de a decide cum pot fi utilizate instrumentele din tehnologia informației și a comunicării la atingerea acestora. Contextul educațional s-a adaptat vremurilor actuale, profesorii devin ghizi și designeri ai situațiilor de învățare unde tehnologia este o unealtă care trebuie folosită cu măiestrie de către aceștia. Cuvinte cheie: educație fizică, sport, tehnologia informației.
Full-text available
Introduction: Knee osteoarthritis (OA) is a chronic musculoskeletal disease that is associated with mortality, disability, and low quality of life. In Hungary, the number of patients diagnosed with severe knee osteoarthritis is dramatically increasing yearly. Objective: This study aims to assess the quality of life among patients with severe knee osteoarthritis who undergo knee replacement surgery after one month to assess their quality of life (QoL). Material and Method: Ten patients (6 female, 4 male, 70±4 years, 30.7±3.4 kg/m2) with severe knee osteoarthritis were included from an orthopedic clinic in Pécs, Hungary. The SF-36 questionnaire (Hungarian version) was used to assess QoL of the patients one month prior to knee replacement surgery. Results: The participants with severe knee OA reported allow overall average of pain (40.95%), role limitations due to physical health (42.5%), and role limitations due to emotional problems (46.7%) that reduced their QoL. In addition, there are significant differences between women and men in some domains. Women had significantly lower physical functioning and role limitations due to emotional problems than men, by 42.8% (p=0.03) and 73.3% (P=0.005), respectively. Moreover, women had a higher feeling of pain than men; however, the differences was insignificant. Conclusions: Patients with severe knee osteoarthritis have low quality of life and severe pain during daily activities. Furthermore, women with severe knee OA had significantly higher pain and lower quality of life than men due to their emotional status. Further studies with large sample sizes are needed. Received 2022 June 30; Revised 2022 July 15; Accepted 2022 July 21; Available online 2022 June 30; Available print 2022 August 30.
Full-text available
Winter tourism has been repeatedly identified as vulnerable to global climate change due to dimin- ished snow conditions required for alpine and nordic skiing that dominate the winter tourism market. Vulnerability to climate change, however, is not only depending on the impacts of global warming on natural snow conditions but also on the tourims stakeholder's willingness and ability to adapt to chang- ing circumstances. First, the impacts of climate change on the number of naturally snow-reliable ski areas in the Alps will be presented. Second, the potential as well as the limitiations of two selected adaptation strategies - artificial snowmaking and all-year tourism - will be highlighted. And finally, the significance of climate change as a decisive variable in determining the future of Alpine (winter) tourism will be discussed, keeping in mind that the tourism sector will be affected by many factors over the next decades.
Full-text available
The major patterns of interannual Swiss Alpine snow pack variability were determined and their relation to local and large-scale climate variability and recent trends was investigated. The snow variables considered were the seasonally averaged new snow sum, snow depth and snow days for winter (DJF) in the period 1958-1999. Three major patterns of large-scale snow variability were identified. The first pattern explains ∼50% of total variance and extends over the entire area except the southernmost parts. The second pattern explains ∼15 % of total variance and has a dipole structure with a maximum on the northern and a strong minimum on the southern slope of the Alps. The third pattern (∼10 % of total variance) is height dependent with a strong maximum at lowland stations and a minimum at high stations. In contrast to the first and second pattern, the third pattern's time component shows a distinct trend. It is well correlated with the 0°C isotherm which increased from ∼600 m a.s.l. in the 1960s to ∼900 m a.s.l. in the late 1990s and could be related to climate change. Variability in the first new snow sum pattern was primarily related to total precipitation anomalies. In contrast, variability in the first snow day pattern was primarily related to temperature anomalies. The dominance of precipitation for new snow sums and the dominance of temperature for snow days is physically consistent with the former being controlled by accumulation only and the latter by accumulation and ablation. The surface pressure anomaly pattern linked to the first new snow sum pattern is centred over southeastern Europe, resembling the Euro-Atlantic blocking pattern. For snow days the corresponding pressure anomaly is shifted further southeastward. The second snow pattern is mainly influenced by an East Atlantic like pattern, whereas only the third (height and temperature dependent) pattern is strongly linked to the North Atlantic Oscillation index.
Full-text available
Winter tourism is highly sensitive to climate change. The sufficiently studied altitudinally dependent line of natural snow reliability is losing its relevance for skilift operators in Austria, where 59% of the ski area is covered by artificial snowmaking. But the diffusion of snowmaking facilities cannot be monocausally linked to climate change, as trends in tourism, prestige, and competitive advantage are important factors. Despite the fact that snowmaking is limited by climatological factors, skilift operators trust in technical improvements and believe the future will not be as menacing as assumed by recent climate change impact studies. The aim of the present study is to define reasons for the diffusion of snowmaking systems and to determine whether snowmaking can be a viable adaptation strategy despite ongoing warming, using a simple degree-day model. Results obtained with this method of assessing technical snow reliability show that current snowmaking intensity will not be sufficient to guarantee the desired 100-day season at elevations below 1500-1600 m. Snowmaking will still be possible climatically even at lower elevations, but the required intensification of capacity will lead to significantly higher operation costs.
Full-text available
Snow and weather observations at Weissfluhjoch were initiated in 1936, when a research team set a snow stake and started digging snow pits on a plateau located at 2,540 m asl above Davos, Switzerland. This was the beginning of what is now the longest series of daily snow depth, new snow height and bi-monthly snow water equivalent measurements from a high-altitude research station. Our investigations reveal that the snow depth at Weissfluhjoch with regard to the evolution and inter-annual variability represents a good proxy for the entire Swiss Alps. In order to set the snow and weather observations from Weissfluhjoch in a broader context, this paper also shows some comparisons with measurements from five other high-altitude observatories in the European Alps. The results show a surprisingly uniform warming of 0.8°C during the last three decades at the six investigated mountain stations. The long-term snow measurements reveal no change in mid-winter, but decreasing trends (especially since the 1980s) for the solid precipitation ratio, snow fall, snow water equivalent and snow depth during the melt season due to a strong temperature increase of 2.5°C in the spring and summer months of the last three decades.
Full-text available
[1] Updated European averaged autumn and winter surface air temperature (SAT) timeseries indicate that the autumn 2006 and winter 2007 were extremely likely (>95%) the warmest for more than 500 years. In both seasons, the European SAT anomaly is widespread with anomalies up to three standard deviations from normal. The anomalous warmth is associated with strong anticyclonic conditions and warm air advection from south west. Phenological impacts related to this warmth included some plant species having a partial second flowering or extended flowering till the beginning of winter. Species that typically flower in early spring were found to have a distinct earlier flowering after winter 2007.
A study of snow statistics over the past 50 years at several climatological stations in the Swiss Alps has highlighted periods in which snow was either abundant or not. Periods with relative low snow amounts and duration are closely linked to the presence of persistent high surface pressure fields over the Alpine region during late Fall and in Winter. These high pressure episodes are accompanied by large positive temperature anomalies and low precipitation, both of which are unfavorable for snow accumulation during the Winter. The fluctuations of seasonal to annual pressure in the Alpine region is strongly correlated with anomalies of the North Atlantic Oscillation index, which is a measure of the strength of the westerly flow over the Atlantic. This implies that large-scale forcing, and not local or regional factors, plays a dominant role in controling the timing and amount of snow in the Alps, as evidenced by the abundance or dearth of snow over several consecutive years. Furthermore, since the mid-1980s, the length of the snow season and snow amount have substantially decreased, as a result of pressure fields over the Alps which have been far higher and more persistent than at any other time this century. A detailed analysis of a number of additional Alpine stations for the last 15 years shows that the sensitivity of the snow-pack to climatic fluctuations diminishes above 1750 m. In the current debate on anthropogenically-induced climatic change, this altitude is consistent with other studies and estimates of snow-pack sensitivity to past and projected future global warming.
Swiss Alpine snow cover is varying substantially on interannual to decadal time scales. In the late 20th century decreases in snow days (SD) have been observed for stations below 1300 m asl. A regression model is used in this work to quantify the importance of mean temperature and precipitation as well as large-scale climate variability in order to explain the observed trends. Both, local- and large-scale models account for a modest fraction of the observed seasonal variability. Results suggest that the recent decrease in low altitude snow cover can mainly be attributed to an increase in temperature. Differences are found for northern and southern Switzerland concerning the influence of large-scale climate patterns. In contrast to southern Alpine regions, northern Alpine interannual SD variability is almost unaffected by the North Atlantic Oscillation (NAO). Decadal trends, however, can be explained via temperature only by a model that includes the explanatory variable NAO.