Climate risks and their impact on agriculture and forests in Switzerland

Abstract

There is growing evidence that, as a result of global climate change, some of the most severe weather events could become more frequent in Europe over the next 50 to 100 years. The paper aims to (i) describe observed trends and scenarios for summer heat waves, windstorms and heavy precipitation, based on results from simulations with global circulation models, regional climate models, and other downscaling procedures, and (ii) discuss potential impacts on agricultural systems and forests in Switzerland. Trends and scenarios project more frequent heavy precipitation during winter corresponding, for example, to a three-fold increase in the exceedance of today's 15-year extreme values by the end of the 21st century. This increases the risk of large-scale flooding and loss of topsoil due to erosion. In contrast, constraints in agricultural practice due to waterlogged soils may become less in a warmer climate. In summer, the most remarkable trend is a decrease in the frequency of wet days, and shorter return times of heat waves and droughts. This increases the risk of losses of crop yield and forage quality. In forests, the more frequent occurrence of dry years may accelerate the replacement of sensitive tree species and reduce carbon stocks, and the projected slight increase in the frequency of extreme storms by the end of the century could increase the risk of windthrow. Some possible measures to maintain goods and services of agricultural and forest ecosystems are mentioned, but it is suggested that more frequent extremes may have more severe consequences than progressive changes in means. In order to effectively decrease the risk for social and economic impacts, long-term adaptive strategies in agriculture and silviculture, investments for prevention, and new insurance concepts seem necessary.

Explaining gender differences in private forest risk management

“…In addition, climate change is expected to lead to increased risk of damage from fungi, insects, spring frost, and wind (Statens Offentliga Utredningar (SOU) 2007). However, implementing pro-active risk management strategies may reduce the risk of damage in the future (Fuhrer et al 2006;Bouriaud et al 2015;Beguin et al 2016). …”

“…To make forests more resistant to threats associated with climate change (e.g. increased risk of damage from wind and insects), silvicultural measures, such as more mixed forests and varying rotation length, may be implemented (Fuhrer et al 2006;Bouriaud et al 2015). Strategies used to reduce the risk of damage by animal browsing include treatments, plantation fencing, and hunting (Beguin et al 2016).…”

Forest Carbon Sequestration: The Impact of Forest Management

“…However, forests can easily become carbon sources rather than carbon sinks (Kurz and Apps, 1999, Gracia et al, 2001, Reichstein et al, 2002. Changes in the regimes of natural disturbances such as fire, pests or drought (Fuhrer et al, 2006, Sohngen et al, 2005, Ciais et al, 2005, can affect major forest functions, forestry outputs and forest stability. Metsaranta et al (2010) reported that Canadian forests will likely be carbon sources until 2030, and become carbon sinks after 2050, based on simulations of the impact of future fire and insect disturbances.…”

Climate and land-use changes affecting river sediment and brown trout in alpine countries—a review

“…While a significant negative trend for total annual precipitation over the last two centuries in the southern part of the Alps has been shown, the average trend was positive for the northern alpine region, particularly in winter and spring (Brunetti et al 2006). An increase in amount and duration of torrential rain events, especially in winter and autumn months, during the last three to five decades has been demonstrated mainly for the northern alpine region while there is a slight positive, nonsignificant trend for the southern parts (Schmidli and Frei 2005;Fuhrer et al 2006;Diodato and Mariani 2007). In the south, these extreme events alternate with increasing dry periods in autumn and spring (Schmidli and Frei 2005).…”

“…However, particularly due to insufficient data availability, the linkage to riverbed clogging (reduction in riverbed interstitial flow from sediment deposition) and direct or indirect impairment on fish health by suspended sediments could not be evaluated (Fischnetz 2004). One potential cause of increased erosion and sediment loads in rivers could be increased temperatures, altered precipitation patterns (strength, timing and altitude), changes in snow cover and seasonal snow melting caused by climate change (IPCC 2007;Fuhrer et al 2006;Beniston 2006). These may have led to increased river runoff, especially in winter and in spring, and altered seasonal and regional sediment load and riverbed clogging patterns.…”