Australia: State of the Climate
The climate is changing and human activity is almost certainly to blame. That’s the conclusion of a new report called State of the climate just released by the Australian CSIRO and the Bureau of Meteorology.
This snapshot provides observations and analysis of Australia’s climate and the factors that influence it. Two organisations, CSIRO and the Australian Bureau of Meteorology have combined to present this current picture of Australia’s climate.
The Bureau of Meteorology has been observing and reporting on weather in Australia for over 100 years, and CSIRO has been conducting atmospheric and marine research for over 60 years.The snapshot is sourced from peer reviewed data on temperature, rainfall, sea level, ocean acidification, and carbon dioxide and methane levels in the atmosphere.
Some key facts from the report:
- Since 1960 the mean temperature in Australia has increased by about 0.7°C
- The number of days with record hot temperatures has increased each decade over the past 50 years
- There have been fewer record cold days each decade
- 2000 to 2009 was Australia’s warmest decade on record
- The geographic distribution of rainfall has changed significantly over the past 50 years
- From 1870 to 2007, the global average sea level rose by close to 200mm
- The rate of sea level rise increased during the 20th century
- During 1993 to 2009 sea level rise has been 1.5 to 3mm per year in the south and east of Australia and 7 to 10mm per year in the north and west
- Sea surface temperatures around Australia have increased by about 0.4°C in the past 50 years
- Ocean Acidification is now being observed at the base of the food chain in the Southern Ocean
What this means.
Australia will be hotter in coming decades
Australian average temperatures are projected to rise by 0.6 to 1.5°C by 2030. If global greenhouse gas emissions continue at current levels, warming is projected to be in the range of 2.2 to 5.0°C by 2070. Warming is projected to be lower near the coast and in Tasmania and higher in central and north-western Australia. These changes will be felt through an increase in the number of hot days.
Much of Australia will be drier in coming decades
In Australia compared to the period 1981-2000, decreases in rainfall are likely in the decades to come in south- ern areas of Australia during winter, in southern and eastern areas during spring, and in south-west Western Australia during autumn. An increase in the number of dry days is expected across the country, but it is likely that there will be an increase in intense rainfall events in many areas.
It is very likely that human activities have caused most of the global warming observed since 1950
There is greater than 90% certainty that increases in greenhouse gas emissions have caused most of the global warming since the mid-20th century. International research shows that it is extremely unlikely that the observed warming could be explained by natural causes alone. Evidence of human influence has been detected in ocean warming, sea-level rise, continental-average temperatures, temperature extremes and wind patterns. CSIRO research has shown that higher greenhouse gas levels are likely to have caused about half of the winter rainfall reduction in south-west Western Australia.
Climate change is real
Our observations clearly demonstrate that climate change is real. CSIRO and the Bureau of Meteorology will continue to provide observations and research so that Australia’s responses are underpinned by science of the highest quality.
The CSIRO and the BOM are two of Australia’s most trusted, most respected scientific institutions. This report comes out at a time when many members of the public have been confused by the non-stop lobbying by fossil fuel industries, by charlatan academics and by a Government whose response to climate change has been lacklustre to say the least. Climate change is here, it’s real and it’s something Australians have to address head-on. — DS