Insights from an European climate change network

Background/Question/Methods

Climate change acts on a global scale, affects many different ecosystem types under many different site conditions and by a multitude of stressors and combinations of these. The traditional experimental approach has been to select a relevant site and design an experiment applying a realistic scenario of one or several climate change related factors. The underlying assumption has typically been that such an experiment, if designed properly, will provide elements of general and generic understanding which can be extrapolated to larger temporal and spatial scales, for example by modelling. However, such experiments may not always be easily extrapolated simply because the “single site - single scenario” approach only provides a single dot on the response curve and we often do not know the shape of that curve.

One approach to gain more insight into the generality of the responses and understand the response curve/surface for a given process is to conduct similar experiments across a range of sites with different characteristics and under different climatic conditions. In Europe several experimental multisite approaches have been conducted, among those most successfully the INCREASE project, which consist of 6+1 shrubland sites across a European temperature and precipitation gradient where temperature and precipitation has been manipulated for 13 years. The additional 1 site is the Danish CLIMAITE site including 7 years of multifactorial climate change manipulation with elevated CO₂, temperature and precipitation. In addition to the single site responses, INCREASE has provided new understanding of the variability in response of both biological and biogeochemical processes to climatic perturbations. It has also demonstrated a strong resilience in ecosystems to moderate perturbations, which has to be taken into account when new experiments are to be designed and it has demonstrated the importance of the ecosystem state for the response to changes.

Results/Conclusions

The key results will be presented and experience, challenges and opportunities from INCREASE will be with particular focus on guidance of new experimental designs.

These include:

• needs for comparable experimental designs
• needs for coordinated protocols
• needs for common data policy and data handling
• guidelines for new experimental approaches
• presentation of a new European experimental infrastructure ANAEE