A snow gun is seen on a skiing slope in Kranjska gora December 14, 2011. Skiing season will start after Christmas in Slovenia due to the lack of snow at skiing centres.
REUTERS/Srdjan Zivulovic (SLOVENIA - Tags: ENVIRONMENT)

A snow gun is seen on a skiing slope in Kranjska gora December 14, 2011. Skiing season will start after Christmas in Slovenia due to the lack of snow at skiing centres.
REUTERS/Srdjan Zivulovic (SLOVENIA - Tags: ENVIRONMENT)

A snow gun is seen on a skiing slope in Kranjska gora December 14, 2011. Skiing season will start after Christmas in Slovenia due to the lack of snow at skiing centres.
REUTERS/Srdjan Zivulovic (SLOVENIA - Tags: ENVIRONMENT)

Seats are seen on a chair lift on the skiing slope in Kranjska gora December 14, 2011. Skiing season will start after Christmas in Slovenia due to the lack of snow at skiing centres.
REUTERS/Srdjan Zivulovic (SLOVENIA - Tags: ENVIRONMENT)

A worker walks on a soggy skiing slope in Kranjska Gora December 14, 2011. Skiing season will start after Christmas in Slovenia due to the lack of snow at skiing centres.
REUTERS/Srdjan Zivulovic (SLOVENIA - Tags: ENVIRONMENT)

An aerial view shows snowless slopes on the Rosshuette mountain in the western Austrian village of Seefeld November 22, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT TPX IMAGES OF THE DAY)

Snow cannons produce artificial snow in the eastern Swiss mountain resort of Davos November 26, 2011. REUTERS/Arnd Wiegmann (SWITZERLAND - Tags: ENVIRONMENT SOCIETY TRAVEL)

Snow cannons produce artificial snow in the eastern Swiss mountain resort of Davos November 26, 2011. REUTERS/Arnd Wiegmann (SWITZERLAND - Tags: ENVIRONMENT SOCIETY TRAVEL)

A snow cannon produces artificial snow in the eastern Swiss mountain resort of Davos November 26, 2011. REUTERS/Arnd Wiegmann (SWITZERLAND - Tags: ENVIRONMENT SOCIETY TRAVEL)

Skiers slide down a piste during sunny autumn weather on Mount Jakobshorn (2590m/8497 ft) in the eastern Swiss mountain resort of Davos November 26, 2011. Davos opened the season in parts of the Parsenn and Mount Jakobshorn ski regions on November 25. REUTERS/Arnd Wiegmann (SWITZERLAND - Tags: ENVIRONMENT SOCIETY TRAVEL)

Skiers sit in a chair lift during sunny autumn weather on Mount Jakobshorn (2590m/8497 ft) in the eastern Swiss mountain resort of Davos November 26, 2011. Davos opened the season in parts of the Parsenn and Mount Jakobshorn ski regions on November 25. REUTERS/Arnd Wiegmann (SWITZERLAND - Tags: ENVIRONMENT SOCIETY TRAVEL)

Skiers slide down pistes during sunny autumn weather on Mount Jakobshorn (2590m/8497 ft) in the eastern Swiss mountain resort of Davos November 26, 2011. Davos opened the season in parts of the Parsenn and Mount Jakobshorn ski regions on November 25. REUTERS/Arnd Wiegmann (SWITZERLAND - Tags: ENVIRONMENT SOCIETY TRAVEL)

Skiers slide down pistes during sunny autumn weather on Mount Jakobshorn (2590m/8497 ft) in the eastern Swiss mountain resort of Davos November 26, 2011. Davos opened the season in parts of the Parsenn and Mount Jakobshorn ski regions on November 25. REUTERS/Arnd Wiegmann (SWITZERLAND - Tags: ENVIRONMENT SOCIETY TRAVEL)

Skiers slide down pistes during sunny autumn weather on Mount Jakobshorn (2590m/8497 ft) in the eastern Swiss mountain resort of Davos November 26, 2011. Davos opened the season in parts of the Parsenn and Mount Jakobshorn ski regions on November 25. REUTERS/Arnd Wiegmann (SWITZERLAND)

A skier slides down a piste during sunny autumn weather on Mount Jakobshorn (2590m/8497 ft) in the eastern Swiss mountain resort of Davos November 26, 2011. Davos opened the season in parts of the Parsenn and Mount Jakobshorn ski regions on November 25. REUTERS/Arnd Wiegmann (SWITZERLAND - Tags: ENVIRONMENT SOCIETY TRAVEL)

Skiers slide down a piste during sunny autumn weather on Mount Jakobshorn (2590m/8497 ft) in the eastern Swiss mountain resort of Davos November 26, 2011. Davos opened the season in parts of the Parsenn and Mount Jakobshorn ski regions on November 25. REUTERS/Arnd Wiegmann (SWITZERLAND - Tags: ENVIRONMENT SOCIETY TRAVEL)

Skiers walk past a snowless piste of a ski school for children during sunny autumn weather in the estern Swiss mountain resort of Davos November 26, 2011. Davos opened the season in parts of the Parsenn and Mount Jakobshorn ski regions on November 25. REUTERS/Arnd Wiegmann (SWITZERLAND - Tags: ENVIRONMENT SOCIETY TRAVEL)

A patch of artificial snow from a snow cannon test is seen in front of Mount Rothorn (2865 m/9399 ft) during sunny autumn weather in the eastern Swiss mountain resort of Lenzerheide November 25, 2011. Following an extremely dry November with high temperatures, some ski resorts in the Swiss Alps have postponed their season opening weekends due to a lack of snow. REUTERS/Arnd Wiegmann (SWITZERLAND - Tags: ENVIRONMENT SOCIETY TRAVEL)

Patches of artificial snow from a snow cannon test lie on a ski piste during sunny autumn weather in the eastern Swiss mountain resort of Lenzerheide November 25, 2011. Following an extremely dry November with high temperatures, some ski resorts in the Swiss Alps have postponed their season opening weekends due to a lack of snow. REUTERS/Arnd Wiegmann (SWITZERLAND - Tags: ENVIRONMENT SOCIETY TRAVEL)

Patches of artificial snow from a snow cannon tests are seen on snowless slopes during sunny autumn weather in Lenzerheide, November 25, 2011. Following an extremely dry November with high temperatures, some ski resorts in the Swiss Alps have postponed their season opening weekends due to a lack of snow. REUTERS/Christian Hartmann (SWITZERLAND - Tags: ENVIRONMENT TRAVEL)

Patches of artificial snow from a snow cannon tests (bottom) are seen on snowless slopes during sunny autumn weather in Lenzerheide, November 25, 2011. Following an extremely dry November with high temperatures, some ski resorts in the Swiss Alps have postponed their season opening weekends due to a lack of snow. REUTERS/Christian Hartmann (SWITZERLAND - Tags: ENVIRONMENT TRAVEL)

An idle ski-lift is seen in front of the snowless Swiss Alps during sunny autumn weather in Lenzerheide, November 25, 2011. Following an extremely dry November with high temperatures, some ski resorts in the Swiss Alps have postponed their season opening weekends due to a lack of snow. REUTERS/Christian Hartmann (SWITZERLAND - Tags: ENVIRONMENT TRAVEL)

Patches of artificial snow from snow cannon tests are seen on snowless slopes under an idle ski-lift during sunny autumn weather in Lenzerheide, November 25, 2011. Following an extremely dry November with high temperatures, some ski resorts in the Swiss Alps have postponed their season opening weekends due to a lack of snow. REUTERS/Christian Hartmann (SWITZERLAND - Tags: ENVIRONMENT TRAVEL)

An idle ski-lift is seen in front of the snowless Swiss Alps during sunny autumn weather in Lenzerheide, November 25, 2011. Following an extremely dry November with high temperatures, some ski resorts in the Swiss Alps have postponed their season opening weekends due to a lack of snow. REUTERS/Christian Hartmann (SWITZERLAND - Tags: ENVIRONMENT TRAVEL)

A sign for cross-country skiers is pictured during sunny autumn weather in the eastern Swiss mountain resort of Lenzerheide November 25, 2011. Following an extremely dry November with high temperatures, some ski resorts in the Swiss Alps have postponed their season opening weekends due to a lack of snow. REUTERS/Arnd Wiegmann (SWITZERLAND - Tags: ENVIRONMENT SOCIETY TRAVEL)

An out of service ski-lift is seen in front of the snowless Swiss Alps during sunny autumn weather in Lenzerheide, November 25, 2011. Following an extremely dry November with high temperatures, some ski resorts in the Swiss Alps have postponed their season opening weekends due to a lack of snow. REUTERS/Christian Hartmann (SWITZERLAND - Tags: ENVIRONMENT TRAVEL)

A horse grazes in meadow next to a patch of artificial snow from a snow cannon test, during sunny autumn weather in Lenzerheide, November 25, 2011. Following an extremely dry November with high temperatures, some ski resorts in the Swiss Alps have postponed their season opening weekends due to a lack of snow. REUTERS/Arnd Wiegmann (SWITZERLAND - Tags: ENVIRONMENT TRAVEL)

A horse grazes in meadow next to a patch of artificial snow from a snow cannon test, during sunny autumn weather in Lenzerheide, November 25, 2011. Following an extremely dry November with high temperatures, some ski resorts in the Swiss Alps have postponed their season opening weekends due to a lack of snow. REUTERS/Christian Hartmann (SWITZERLAND - Tags: ENVIRONMENT TRAVEL)

Horses graze in a snowless meadow next to a patch of artificial snow from a snow cannon test during sunny autumn weather in the eastern Swiss mountain resort of Lenzerheide November 25, 2011. Following an extremely dry November with high temperatures, some ski resorts in the Swiss Alps have postponed their season opening weekends due to a lack of snow. REUTERS/Arnd Wiegmann (SWITZERLAND - Tags: ENVIRONMENT TRAVEL ANIMALS TPX IMAGES OF THE DAY)

A horse grazes in a snowless meadow next to a patch of artificial snow from a snow cannon test, during sunny autumn weather in Lenzerheide, November 25, 2011. Following an extremely dry November with high temperatures, some ski resorts in the Swiss Alps have postponed their season opening weekends due to a lack of snow. REUTERS/Christian Hartmann (SWITZERLAND - Tags: ENVIRONMENT TRAVEL)

A cross country skier uses an artificial track as he passes a snow making machine in the western Austrian village of Seefeld November 25, 2011. Following an extremely dry November with high temperatures, some ski resorts in the Austrian Alps have cancelled their season opening weekends due to a lack of snow.REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT SKIING)

Cross country skiers use an artificial snow track in the western Austrian village of Seefeld November 25, 2011. Some ski resorts in the Austrian Alps have cancelled their season opening weekends, following no snow for 31 days and high temperatures. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: SPORT SKIING ENVIRONMENT)

Cross country skiers use an artificial snow track in the western Austrian village of Seefeld November 25, 2011. Some ski resorts in the Austrian Alps have cancelled their season opening weekends, following no snow for 31 days and high temperatures. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: SPORT SKIING ENVIRONMENT)

Cross country skiers use an artificial snow track in the western Austrian village of Seefeld November 25, 2011. Some ski resorts in the Austrian Alps have cancelled their season opening weekends, following no snow for 31 days and high temperatures. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: SPORT SKIING ENVIRONMENT)

A cross country skier uses an artificial snow track in the western Austrian village of Seefeld November 25, 2011. Following no snow for 31 days and high temperatures, some ski resorts in the Austrian Alps have cancelled their season opening weekends. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: SPORT SKIING ENVIRONMENT TPX IMAGES OF THE DAY)

A cross country skier uses an artificial snow track in the western Austrian village of Seefeld November 25, 2011. Following an extremely dry November, some ski resorts in the Austrian Alps have cancelled their season opening weekends due to a lack of snow. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: SPORT SKIING)

People enjoy the sunny autumn weather over the fog next to the chapel of the snowless central Swiss ski resort of Stoss, at 1,305 m above sea level, near Lake Lucern, November 24, 2011. REUTERS/Christian Hartmann (SWITZERLAND - Tags: ENVIRONMENT TRANSPORT TRAVEL)

Ski-lift perches are seen over the snowless slopes of the central Swiss ski resort of Stoss during sunny autumn weather at 1,305 m above sea level, near Lake Lucern, November 24, 2011. In the background are the Mythen peaks, at 1,808 m above sea level. REUTERS/Christian Hartmann (SWITZERLAND - Tags: ENVIRONMENT TRANSPORT TRAVEL)

Ski-lift perches are seen over the snowless slopes of the central Swiss ski resort of Stoss during sunny autumn weather at 1,305 m above sea level, near Lake Lucern, November 24, 2011. In the background are the Mythen peaks, at 1,808 m above sea level. REUTERS/Christian Hartmann (SWITZERLAND - Tags: ENVIRONMENT TRANSPORT TRAVEL)

People enjoy the sunny autumn weather over the fog next to the chapel of the snowless central Swiss ski resort of Stoss, at 1,305 m above sea level, near Lake Lucern, November 24, 2011. REUTERS/Christian Hartmann (SWITZERLAND - Tags: ENVIRONMENT TRANSPORT TRAVEL)

Ski-lift perches are seen over the snowless slopes of the central swiss ski resort of Stoss during sunny autumn weather at 1,305 m above sea level, near Lake Lucern, November 24, 2011. In the background are the Mythen peaks, at 1,808 m above sea level. REUTERS/Christian Hartmann (SWITZERLAND - Tags: ENVIRONMENT TRANSPORT TRAVEL)

Ski-lift perches are seen over the snowless slopes of the central Swiss ski resort of Stoss during sunny autumn weather at 1,305 m above sea level, near Lake Lucern, November 24, 2011. REUTERS/Christian Hartmann (SWITZERLAND - Tags: ENVIRONMENT TRANSPORT TRAVEL BUSINESS)

Ski-lift perches are seen over the snowless slopes of the central Swiss ski resort of Stoss during sunny autumn weather at 1,305 m above sea level, near Lake Lucern, November 24, 2011. REUTERS/Christian Hartmann (SWITZERLAND - Tags: ENVIRONMENT TRANSPORT TRAVEL)

An aerial view shows snowless slopes on Mutter Alm ski resort in the western Austrian city of Innsbruck November 22, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT)

An aerial view shows Germany's highest mountain, the 2,962 metre (9,718 feet) Zugspitze, near the southern Bavarian resort of Garmisch-Partenkirchen November 22, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT)

An aerial view shows partly snow covered mountains in the western Austrian province of Tyrol November 22, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT)

An aerial view shows the snowless Nordkette mountains in the western Austrian city of Innsbruck November 22, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT)

An aerial view shows snowless slopes on Patscherkofel mountain in the western Austrian city of Innsbruck November 22, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT)

An aerial view shows snowless slopes on Patscherkofel mountain in the western Austrian city of Innsbruck November 22, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT)

An aerial view shows snowless slopes on the Seegrube mountain in the western Austrian city of Innsbruck November 22, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT)

An aerial view shows snowless slopes on the Seegrube mountain in the western Austrian city of Innsbruck November 22, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT)

An aerial view shows snowless slopes on the Rosshuette mountain in the western Austrian village of Seefeld November 22, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT)

An aerial view shows snowless slopes on the Rosshuette mountain in the western Austrian village of Seefeld November 22, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT)

An aerial view shows snowless slopes on the Rosshuette mountain in the western Austrian village of Seefeld November 22, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA)

Dried grass is pictured on a snowless slope on Patscherkofel mountain in the western Austrian city of Innsbruck November 21, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT)

A snow making machine stands on a snowless slope on Patscherkofel mountain in the western Austrian city of Innsbruck November 21, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT)

Snow making machines stand on a snowless slope on Patscherkofel mountain in the western Austrian city of Innsbruck November 21, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT)

Snowless slopes of the western Austrian ski resort of Seegrube mountain are pictured in Innsbruck November 21, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT)

A snow making machine stands on a snowless slope on Patscherkofel mountain in the western Austrian city of Innsbruck November 21, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT)

A snow making machine stands on a snowless slope on Patscherkofel mountain in the western Austrian city of Innsbruck November 21, 2011. REUTERS/Dominic Ebenbichler (AUSTRIA - Tags: ENVIRONMENT SPORT)