by Jeni Bone
The loss of native species, significant damage to coastal infrastructure and a profoundly altered Great Barrier Reef due to climate change are our likely fate, according to the latest UN report on climate change.
Coral bleaching - a reality.
The Intergovernmental Panel on Climate Change report, delivered to the world’s governments in Japan this week, states there is 'significant change in community composition and structure of coral reefs and other ecosystems and risk of loss of some native species in Australia' as a result of warming temperatures and ocean acidification.
Since 1950, Australia has warmed by between 0.4C and 0.7C, the sea level rising by around 70mm and a 'greater frequency and intensity of droughts and heatwaves', the report states.
The report, the first update on impacts in seven years, finds there is 'high confidence' that climate change is causing 'increased frequency and intensity of flood damage to infrastructure and settlements in Australia and New Zealand'.
This scenario is leading to increasing risks for 'coastal infrastructure and low-lying ecosystems' in Australia, threatening 'widespread damage towards the upper end of projected sea-level-rise ranges.'
As oceans warm and the water acidifies, the Great Barrier Reef, like many reefs around the world, is set to decline, according to the IPCC. The vast reef, which may be declared ‘in danger’ by the World Heritage Committee when it meets in June, is 'highly vulnerable' to warming and acidification, the report found.
The reef will suffer from increasing bleaching events, which is when corals start to die due to excess heat, while warming oceans will push exotic tropical species further south into colder waters near Tasmania.
All this in peril
On land, climate change is 'expected to be associated with rising snow lines, more frequent hot extremes, less frequent cold extremes, and increasing extreme rainfall related to flood risk in many locations'.
Climate change is already taking its toll on Australians’ health, the IPCC states, with increasing numbers of people now dying in summer rather than winter.
'In Australia, the number of ‘dangerously hot’ days, when core body temperatures may increase by (more than) 2C and outdoor activity is hazardous, is projected to rise from the current 4-6 days per year to 33-45 days per year by 2070,' the report states.
Some of Australia’s most recognisable creatures face a challenging future, the IPCC report states, with native species set to 'suffer from range contractions, and some may face local or even global extinction.' Koalas, gliders, quokkas, platypus and several species of birds and fish will all suffer from shrinking habitats as temperatures increase, even under the most optimistic scenarios.
Australia is set to experience a 'significant reduction in agricultural production in the Murray-Darling Basin and far south-eastern and south-western Australia if scenarios of severe drying are realised', the report states.
More efficient water use will aid matters, but there will still be 'severe consequences' for ecosystems and rural communities if there is major drying.
Economically, Australia would see its gross national product decline by 7.6% by 2100 if there was no action to tackle climate change. If carbon concentrations in the atmosphere were stabilised, this loss could be less than 2%.
More at www.ipcc.ch