Abstract:
Substantial changes in the structure and functioning of terrestrial, marine and freshwater ecosystems are expected to be triggered by warming of 2-3°C above pre-industrial levels, and by changes in rainfall patterns. In many cases, climate change will exacerbate the ecosystem degradation that already prevails due to multiple anthropogenic pressures. Typical impacts already observed over a wide range of ecosystems and likely to increase in future include changes in the geographical distribution of species, changes in population sizes, changes in lifecycle events, and increased frequency of pest and disease outbreak.