THE Earth's temperature is continuing to rise, the Greenland and the Antarctic ice sheets are losing mass at an increasing rate and the global warming could reach as high as 7 degrees by the turn of the century if greenhouse gases grow unabated, a r review of climate science over the past three years has found.
A temperature rise on this scale would wipe out much of the agriculture in the Murray-Darling Basin, cause thousands of heat-related deaths and bring sea level rises that would dislocate coastal cities of Australia and Asia.
Just weeks before the Copenhagen climate conference, 26 scientists from eight countries have published the most up-to-date review of climate data since the UN's peak scientific body, the Intergovernmental Panel on Climate Change published its report in 2007.
''The message is the warming hasn't stopped,'' said Matthew England of the University of NSW and one of the authors of the report, The Copenhagen Diagnosis. ''Every year this century has been among the top 10 warmest years since instrumental records began.''
This warming trend has continued despite solar brightness being relatively weak over the past three years and the impact of the cooling La Nina event last year.
''While there has been natural short-term fluctuations in temperature, the warning trend has continued,'' the report finds. It underscores a warming trend since the 1970s of a 0.6 degree temperature rise.
The report is confirmation of the scientific case for climate change despite the claims by sceptics of a ''global cooling'' and that climate scientists have suppressed sceptical views.
March last year had the warmest global land temperature of any March measured, and June and August this year had the warmest land and ocean temperatures recorded in the southern hemisphere for those months. Global ocean surface temperatures this year broke records for three consecutive months, June, July and August.
Among the report's more disturbing findings is that several elements in the climate system could pass a ''tipping point'' this century because of human activities leading to abrupt and/or irreversible climate change.
Most of the report concentrates on growing evidence of sea level rise since the last IPCC report. The melting of glaciers and ice caps has greatly increased since the mid-1990s, and the surface of the Greenland ice sheet experiencing summer melt has increased by 30 per cent since 1979.
The authors include one of the leading Australian polar experts, Ian Allison, and among its findings is that ''Antarctica is not cooling: it has warmed overall over at least the past 50 years''.
At the North Pole the ice melt in summer has ''far exceeded the worst-case projections from climate models of the IPCC''.
''Unfortunately, the data now show us that we have underestimated the climate crisis,'' the report finds.
The World Meteorological Organisation yesterday reported that atmospheric carbon dioxide had increased by about 38 per cent since the Industrial Revolution.
If global warming was to be kept to 2 degrees above pre-industrial levels, Professor England said, emissions needed to peak between 2015 and 2020.