Current predictions of extinction risks from climate change vary widely depending on the specific assumptions and geographic and taxonomic focus of each study. I synthesized published studies in order to estimate a global mean extinction rate and determine which factors contribute the greatest uncertainty to climate change–induced extinction risks. Results suggest that extinction risks will accelerate with future global temperatures, threatening up to one in six species under current policies. Extinction risks were highest in South America, Australia, and New Zealand, and risks did not vary by taxonomic group. Realistic assumptions about extinction debt and dispersal capacity substantially increased extinction risks. We urgently need to adopt strategies that limit further climate change if we are to avoid an acceleration of global extinctions. Urban, M.C. (2015), ‘Accelerating extinction risk from climate change’, Science 348 (6234) pp.571-573
17% may be a lot less than 80% but, as this most recent synthesis of available research states, previous estimates of the risk “vary widely” and – given the complexity of ecological systems upon which we rely for food production (etc) – I think most biologists would agree that 17% is still very significant. The scientific and economic consensus is that global CO2 emissions must peak within a decade in order to avoid a runaway greenhouse effect taking hold. Is failing to do this really a risk that humanity should be taking? As the BBC has pointed out, the G7’s stance may well signal (to investors) that the end of fossil fuel era is approaching. However, whereas the G7’s mid-century target is for emissions to be cut 40-70% globally compared with 2010, the scientific and economic consensus makes the G7 appear reckless and/or complacent in suggesting that we can afford to burn fossil fuels at all past 2050. Ultimately, I think the reason for humanity’s collective failure to address the urgency of the need for action on climate change comes down to psychology. After all, being in denial is cheaper than being in therapy. See: http://www.yaleclimateconnections.org/2015/06/the-why-arent-we-acting-on-climate-change-bookshelf/ Addendum Also worthy of note is this attempt by The Carbon Brief to be positive about the G7’s communique: http://www.carbonbrief.org/blog/2015/06/g7-leaders-target-zero-carbon-economy/
I note that climate change didn’t appear at all on the list of concerns at the Bilderberger get-together. Do you think it is just possible that the advice the World leaders are getting from their advisers has changed over the past year or eighteen months, Rick?
The fact that the G7 is itself in denial about the urgency of the need for humanity to decarbonise its power and transport systems ASAP (i.e. rather than take 85 years to do so) just proves that science is not being used as an excuse to over-tax and over-regulate people. https://anthropocenereality.wordpress.com/2013/05/02/there-is-no-new-world-order-conspiracy/
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