German Federal Agency for Nature Conservation (BfN)



Climate change is visible today, and not just from shrinking polar ice caps, retreating glaciers and thawing permafrost. In fact, its impacts can be seen right now on our doorsteps. The apple blossom begins on average ten days earlier than it did in the 1960s, and cuckoos are retreating to cooler uplands because by the time they migrate back north from their winter homes, the eggs of their former lowland hosts are already hatched. For wild plants and animals, warming often means a shift in range northward and to higher altitudes. As different species respond to climate change in different ways and at different rates, ecological communities can change in composition or disappear altogether. Ecosystems and ecological functional relationships can undergo major change.

Neobiota are spreading

While it is becoming too warm for some native species, many exotic, warmth-loving species now feel ‘at home’ in temperate parts of Europe. The fact that palm trees (Chinese windmill palm, Trachycarpus fortunei) now grow in the wild in Switzerland may seem just a curiosity at first sight. But when alien species start to spread so invasively that they pose a threat to native species and human health, they cease to be a mere curiosity and become cause for serious concern. Exotic garden plants such as cherry laurel and Buddleja are increasingly spreading in the wild and may one day displace native species The fiercely allergenic common ragweed is likewise spreading rapidly in Germany. Diseases whose vectors were once restricted to Mediterranean climates (e.g. sand flies, certain tick species and various fungi) are now becoming a problem in countries like Germany.

Climate change is a fact

It should be remembered in this connection that even resolute, well-coordinated international action by all involved would at best be capable of keeping climate change within tolerable bounds. The changes in composition of the Earth’s atmosphere that have already taken place are too large and the climate system responds too slowly for climate change to be halted completely. Even if greenhouse gases were kept down to their year 2000 concentrations, the emissions to date make a further 0.6 °C of further warming (relative to 1980-1999) inevitable by the end of this century (Intergovernmental Panel on Climate Change (IPCC) 2007). Depending on the IPPC (2007), according to the scenario, 20 to 30 percent – in some locations up to 60 percent – of animal and plant species are at increased risk of extinction as a result of climate change (IPCC Fourth Assessment Report, 2007).

A German-language overview of the subject and related BfN activities is provided in ‘Biologische Vielfalt und Klimawandel – Gefahren, Chancen, Handlungsoptionen’ (‘Biodiversity and Climate Change: Dangers, Opportunities and Options for Action’) in the BfN-Skripten publication series ( BfN-Skripten 148, 2006, PDF file 220 KB). Much of the content of these pages originated in this publication.

Last Change: 24/11/2015