Concentrations of CO2

(swissinfo) About 26 billion tons of carbon dioxide are emitted into the atmosphere worldwide each year. Oceans and forests can only absorb around half of these emissions. Atmospheric CO2 levels are about 25% higher than at any other time in the past 650,000 years. The United States produces the equivalent of about 20 tons of CO2 per person every year. The average Swiss accounts for roughly 6 tons - a resident of Senegal only 0.5 tons. Transport is responsible for about a third of CO2 emissions in Switzerland. swissinfo.ch
Matterhorn (Keystone) Temperatures rose globally by 0.8°C in the 20th century. In the Alps, they are rising faster than the global average. By 2050, average Swiss temperatures are predicted to be between half a degree and 4.8°C higher than in 1990. The layer of permafrost that binds mountain surfaces, is expected to thaw as a consequence of hotter summers. It thawed to a depth of nine metres on the 3,000-metre-high Schilthorn in 2003. Wetter winters also means more snow above 2,000 metres, leading to an increase in avalanches. Keystone
Trift glacier (Keystone) The Little Ice Age lasted half a millennium and ended about 1850. There are still around 2,000 glaciers in the Swiss Alps, covering 1,050 square kilometres, or 2.5% of Switzerland's total land area. A rise in temperature of 2.1°C would be sufficient to melt 1,436 glaciers or 17% of the total mass. About 4% of Switzerland's total glacial mass was lost alone in 2006. The Trift Glacier lost 216 metres in length in 2005 – the single biggest loss in the Swiss Alps. Keystone
Zurich airport (Keystone) There were 3.9 billion passenger journeys registered worldwide in 2004, and the figure is expected to double by 2020. Between 60 and 80 million tourists holiday in the Alps each year. Since 1970, the number of holiday residences in Switzerland has nearly quadrupled to 450,000. The annual added value of tourism for the Swiss economy is estimated at SFr13 billion ($10.4 billion), employing 170,000 people. Nearly one in every three workers in cantons Graubünden and Valais are active in the tourism sector. Keystone
Villars (swissinfo) There was a continual increase in snowfall between 1930 and 1980, but since then the trend has been reversed. The ski season in the Bernese Oberland resorts of Adelboden, Mürren and Wengen is now 20 days shorter than it was in 1990. As a rule of thumb, the so-called snowline in winter rises 100 to 150 metres with every increase in temperature of one degree. swissinfo.ch
Adelboden (Keystone) Ski resorts across the Alps continue to invest in snowmaking systems. In Austria, 50% of all ski runs can be blanketed with artificial snow. The figure is only 11.5% in Bavaria and 18% in Switzerland. Snow cannon increase resorts' energy needs and water requirements. They consume about 95 million cubic litres of water each year, the same amount as a city with a population of 1.5 million. About one in three Swiss mountain transport companies cannot afford to upgrade its snowmaking infrastructure. Keystone
Corviglia - St Moritz (Keystone) There are 666 medium to large ski areas across the Alps. If temperatures rise by 1°C, the survival of 166 will be threatened. If temperatures rise by 2°C, the number rises to 266. With a 4°C increase, there could only be 200 left. Swiss ski resorts fare better than those in neighbouring alpine nations. Nearly two-thirds are located above the critical altitude of 1'500m. Keystone