Observations point to a strong and general increase in temperatures in the Alps. Model results show a trend of continuous warming: the mean alpine temperature could increase by 3 to 5°C in summer and 4 to 6°C in winter by the end of the 21st century. General trends concerning observed mean precipitation have not been found. However, heavy precipitation tends to increase in different seasons depending on the territory. Most projections until 2100 suggest a decrease in summer and an increase in winter. Precipitation in winter will increasingly fall as rain rather than snow, leading to fewer days with snow cover. This trend is very likely to continue throughout the 21st century for all alpine countries. A retreat of the alpine glaciers has been observed since the end of the Little Ice Age in about 1850. The disappearance of medium altitude glaciers and a general reduction of glacier volumes and lengths are being predicted for the 21st century.
(see also results of the project ClimChAlp - Climate change, impacts and adaptation strategies in the Alpine Space” and the chapter “Climate change: impacts and adaptation in the Alps - The vulnerability of the Alps to climate change - Climate change and impacts - Future threats - The need to adapt”)
Forests make up more than 40% of the total Austrian territory. The agricultural area including alpine pastures has a comparable share. Mountainous ecosystems, and thus large parts of Austria, are highly vulnerable to changes.
National and international research documents the direct impact of the increase in air temperature and surface water temperature on the physical/chemical and ecological status of surface water bodies. As an example, for 12 Austrian lakes a tendency of water temperature rise as a consequence of the increase in air temperature can be observed. (M. Dokulil, 2009).
Observations show the migration of certain species toward higher altitudes. In the future, the composition of the vegetation group might change in altitude and latitude, inducing a loss of biodiversity, especially of the most endemic species that have a very limited climatic tolerance. Plant communities shift towards higher latitudes and altitudes, hence rare and endemic species with low dispersal capacities could become extinct in the present alpine and nival belts. The projected increase in temperature will likely move the tree line to higher elevations. Warmer temperatures are also expected to enhance the survival rates of forest pests such as the bark beetle or fungi infections. An increased frequency and severity of summer droughts is thought likely, which would threaten tree health and survival. Especially secondary coniferous stands in areas below 1000 m in elevation, which are extremely sensitive to environmental stress factors, are highly vulnerable to climate change. (BMLFUW 2009)
Agriculture is highly exposed to climate change, as farming activities are directly affected by climatic conditions. A change in currently viable areas of crop production is likely while crop yields may rise if moisture is not limited. Increases in the number of extreme events may offset potential benefits and soil degradation (by erosion, leaching, etc.) might be accelerated. As a consequence, a loss of agricultural productivity due to greater duration and/or intensity of precipitation in some areas may occur. On the other hand, droughts occurring in other parts of the country – as in the hot and dry summers of 2000 and 2003 – resulted in parts of Eastern Styria in a distinct decline in groundwater levels at the same time of high peak water demand over the summer months.
Tourism plays an important role in Austria’s economy. A shortening of the winter sports season will probably occur in the next decades (OECD 2007). To some extent, the impacts might be offset by technologies such as snow-making equipment, as long as climate conditions remain within appropriate bounds. However, artificial snow making also raises environmental concerns because of the quantities of energy and water required.
Concerning hydro-power generation, the change of both the seasonal distribution of the reservoir influx and the overall water volume has an impact on the annual production capacity, due to potential changes in runoff extremes. Operating problems regarding water storage for power plants are likely to occur in individual cases, as glaciers are receding.
In general, there is a possible increase in the risk of incidence of vector-borne diseases (including Malaria), also associated with modern transport and tourism flow.
Therefore, to tackle the problem, Austria’s climate policy relies on two pillars: adaptation and mitigation.