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Climate Extremes Matter Most for Biodiversity

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How many species will succumb as temperature increases by more than 1°C, more than 2°C, and eventually to a predicted 4–6°C before the end of the century?

By Ary Hoffmann

The world is expected to warm by up to 4°C by 2070, but it is the extreme weather events associated with climate change that threaten biodiversity the most.

The full text of this article can be purchased from Informit.

One of the main challenges facing biologists today is to work out when biodiversity around the world will start to fall over in a rapidly changing climate. Now that climate change due to anthropogenic causes has become accepted as inevitable and irreversible in the foreseeable future, the challenge is to understand when populations and species will start to decline and then become extinct within an area.

Will it occur within the next decade, or will it take much longer? What fraction of species will succumb as temperature increases by more than 1°C, more than 2°C, and eventually to a predicted 4–6°C before the end of the century? Will these declines then drive changes in entire natural communities of plants, animals and microbes, or is a process of substitution or evolution possible so that some ecosystems continue to persist in a form similar to what they look like today?

Answers to these questions are not merely of academic interest. Functioning ecosystems help to maintain water supplies for irrigation and human consumption, add fertility to soils, provide pollinators and natural pest control to allow for crop production, and provide buffers to detoxify human waste and store carbon. Any deterioration of ecosystem health has massive repercussions for our lives, and it is one of the reasons why ecologists can get frustrated by an unwillingness of the public...

The full text of this article can be purchased from Informit.