CLIMATE change is upon us and its impacts could be abrupt and irreversible.
The latest UN report on global warming predicts that in just 13 years, Queensland's Great Barrier Reef and Wet Tropics will start to suffer significant biodiversity losses.
And by 2030 the east coast and southern parts of Australia and New Zealand will face water shortages.
Agriculture, already facing shortages as countries rush to secure grain supplies for ethanol production to replace petroleum-based fuels, will decline over much of southern and eastern Australia, as will forestry production.
Areas affected by reduced rain will face food and water shortages, malnutrition and increased disease risks.
Coastal development and population growth such as Queensland Transport Minister John Mickel boasted of last week will exacerbate risks from sea level rises and increases in the severity and frequency of storms and coastal flooding.
The Intergovernmental Panel on Climate Change's fourth report warned all nations that warming was unequivocal and had now been proved from observations of global air and ocean temperatures, widespread melting of snow and ice and rising sea levels.
It says satellite data since 1978 showed Arctic sea ice had shrunk by an average 2.7 per cent a decade, with decreases up to 9.8 per cent in summer.
Since 1961 seas had risen an average 1.8mm a year and since 1993 this had sped up to 3.1mm a year.
Rain had increased in North and South America, northern Europe and northern and central Asia but had declined up to 9.8 per cent in Australia's region of southern Asia.
Global greenhouse gas emissions due to human activities had surged 70 per cent between 1970 and 2004.
It warns the elderly, young and chronically ill will suffer from heatwaves.
Warming and sea level rises will continue for centuries, although a wide array of adaptation options are available if governments and communities are prepared to act.
It suggests communities expand rainwater harvesting and reuse of water, relocate sea walls and storm surge barriers and put in place emergency medical plans.
Energy providers should switch from coal to gas, nuclear power and renewables such as solar and geothermal.
It backs the Kyoto Protocol as a notable achievement and the way forward in a global response.
news.com.au
