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ECOSYSTEMS
source: www.ipcc.ch
www.conservation.org
www.washingtonpost.com/ac2/wp-dyn?pagename=article&contentId=A63
153-2004Jan7¬Found=true
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With a rise of up to 1°C above pre-industrial levels, up to 10% of ecosystem areas worldwide will shift... - some hotspots with high biodiversity and protected areas of global importance will begin to suffer climate-induced losses;
- coral reefs will suffer increased bleaching. Range shifts of species and higher risk for some endangered species are likely. In 1998 alone, 16% of the world's coral reefs died from higher temperatures. Although some reefs have since recovered, scientists estimate that more than 1/4 of coral reefs have disappeared due to a combination of temperature changes and human impacts (overfishing, pollution, fishing with poisons or dynamite), and 58% of the coral reefs of the world's oceans are at risk;
- some forest ecosystems will exhibit increased net primary productivity, increased fire frequency and pest outbreaks;
- according to an international team of ecologists, global warming will significantly increase the risk of extinction for up to 37% of terrestrial plant and animal species by 2050*.
With a rise of more than 2°C above pre-industrial levels…- the global share of ecosystems shifting due to climate change is likely to be above 20%, and even more than that in some regions;
- by 2100, sea levels are expected to rise by 9-88 cm if global greenhouse gas emissions are not reduced. This would drown some low-lying islands (e.g. the Maldives) and many coastal regions (e.g. the Bangladesh delta), and cause widespread salt water intrusion;
- scientists estimate a need to reduce emissions by ~400 billion tons C (tC) by 2050 and ~1,000 billion tC by 2100, to keep atmospheric CO2 levels from exceeding double their historical level. Even at these levels, impacts to biodiversity may be severe. Of the necessary emissions reductions, about 100 billion tC could be achieved through forest and other land-based carbon offsets such as restoration of fragmented habitats, reduced impact logging, replacing monoculture farming with agro-forestry, and protection of biodiversity-rich habitat**.
* According to a 19-member international team led by Chris Thomas of Britain's University of Leeds (Nature, January 8, 2004).
** IPPC 2001.
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