Science - facts and fiction
Our new hot topics provide answers to some common climate change science questions - helping you to separate the facts from the fiction.
Opponents of climate change action
There remains some misleading information in the media about climate change and global action to address it. Some commentators claim that international action on climate change is a ‘pretext’ for a central ‘World Government’. Read the full article >
Where can I find reliable information about climate science?
There is a lot of information on climate change science available in the media and on the internet – but how can you ensure what you are reading is independent and not influenced by personal, social or political agendas? Science relies on the continued questioning and challenging of ideas. The peer-review process provides a mechanism to quality control scientific discourse and therefore peer reviewed papers provide a reliable and quality assured source of information on climate change science. Read the full hot topic >
Has global warming stopped?
All measurements of the climate system indicate the long term warming trend is continuing. While there remains some ongoing questioning of whether the observed warming over the 20th century has continued over the past decade, it is inappropriate to use short term data sets to determine long term trends. Read the full hot topic >
Can the warming of the 20th century be explained by natural processes?
It is often claimed that the observed warming of the climate system results from natural climate processes rather than being human-induced. However there are no known natural factors that can explain the observed warming. The Intergovernmental Panel on Climate Change finds it is very likely that 20th century warming is due to the observed increase in anthropogenic greenhouse gases. Read the full hot topic >
If scientists are unable to forecast the next week’s weather accurately, how can they predict the climate in the next 50 to 100 years?
Weather is highly variable, making it difficult to predict over the short term whereas climate is defined as the average weather over the long term. Scientists can project future climate because the underlying processes are well understood. For example, we can predict that winter will be cooler than summer as we understand the underlying processes; however we cannot predict what the weather on a particular day in summer will be. Read the full hot topic >
How reliable are climate models?
The ability of climate models to project future climate is often questioned. While there will always be a range of uncertainty in climate projections, models, which are based on the laws of physics and thoroughly tested, provide credible quantitative estimates of future climate change. Read the full hot topic >
Is there an inconsistency between observed and modelled patterns of warming in the lower atmosphere?
It is commonly claimed that a predicted finger-print of climate change – a warming (or hot spot) in the lower troposphere – is missing from the measurements. Recent reanalysis of the data has established that observations are not inconsistent with the modelled patterns of warming for the troposphere – thus there is no ‘missing’ hot spot. Read the full hot topic >
Understanding current climate over the long term
The Earth’s climate has varied naturally over hundreds of millions of years – why should we believe humans are causing current changes? Understanding past changes between glacial and interglacial periods helps us to understand how unusual the current warming is. For example, the linear warming trend over the past 50 years of 0.13°C per decade is much more rapid than the rate of warming between ice ages and warm interglacial periods of around 0.001°C per decade. Read the full hot topic >
Water vapour is the main greenhouse gas, so why worry about increases in other greenhouse gases that exist in much smaller concentrations?
While there is far more water vapour in the atmosphere than other greenhouse gases, the other greenhouse gases play an important role in influencing our climate. The increase in anthropogenic greenhouse gases is largely responsible for the observed warming of 0.74°C over the 20th century. This warming has had a ‘positive feedback’ as a warmer atmosphere can hold more water vapour – enhancing human induced warming by about 50%. Read the full hot topic >
Department of Climate Change response to Climate Sceptics ‘you have been conned’ television advertisements
The Climate Sceptics Party has recently broadcast advertisements claiming they have scientific evidence that climate change is not occurring. The evidence referred to in these advertisements contains a number of inaccuracies and is not regarded as credible by the broader scientific community. Read the full response >
The Copenhagen Diagnosis: Climate Science Report
This report summarises the key findings in climate science since the publication of the Intergovernmental Panel on Climate Change Fourth Assessment Report in 2007. Read the report on the Copenhagen Diagnosis website
Emails stolen from the Climatic Research Unit of the University of East Anglia
The emails stolen from the Climatic Research Unit of the University of East Anglia do not undermine the conclusions of the Intergovernmental Panel on Climate Change that global warming is ‘unequivocal’ and that ‘most of the observed increase in globally-averaged temperatures since the mid-20th century is very likely due to the observed increase in greenhouse gas concentrations’. Read more >
Bureau of Meteorology Annual Australian Climate Statement 2009
The Bureau of Meteorology has released its Annual Australian Climate Statement for 2009 with temperature data showing that 2009 was Australia’s 2nd warmest year on record and the decade (2000 to 2009) was Australia’s warmest on record. In Australia, each decade since the 1940’s has been warmer than the preceding decade. This is consistent with temperature trends being observed at the global scale and suggests Australia’s climate is increasingly characterised by a trend to warmer temperatures rather than natural variability. As the Bureau notes, trends in Australia’s daily temperature data are consistent with global warming.
The World Meteorological Organization has released a preliminary statement finding that globally 2009 is likely to rank in the top ten warmest years on record with 2000-2009 being the warmest decade on record.
Intergovernmental Panel on Climate Change - Himalayan glaciers
The Intergovernmental Panel on Climate Change (IPCC) has announced publicly that a paragraph on the projected rate of Himalayan glacier melt in the Fourth Assessment Report (AR4) has been based on poorly sourced information. The IPCC has acknowledged its procedures were not applied properly to this paragraph, but maintains the central conclusions of the AR4 are entirely consistent with the underlying science of climate change. Read more >
Climate change science - frequently asked questions
For additional information on some frequently asked questions related to climate change science you can also visit: