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Friday 2 February 2007 (Updated Mon 5 Feb 07)

RAPID ROUNDUP: Climate scientists and Lead Authors respond to IPCC Climate Change Report

Some of the most compelling scientific data on climate change has now been released. It is the first in a series of ground-breaking documents from the Intergovernmental Panel on Climate Change (IPCC).

The full report, known as IPCC WG1 AR4 Final Report can be downloaded here.

National media briefings have also now taken place in Melbourne (Sat 3 Feb) and Adelaide (Mon 5 Feb) Click here for audio files of the speakers and further information on the briefings. In the meantime here is a range of comments from some Australian Lead Authors and other climate experts.

Feel free to use these quotes in your stories or if you want to interview one of these or other experts, contact the AusSMC on (08) 8207 7415 or email us.

Read comments from:

Professor Kurt Lambeck, Professor of Geophysics at the Australian National University (ANU) and President of the Australian Academy of Science.

Professor Neville Nicholls, Lead Author, Chapter 9: Understanding and attributing climate change and climate scientist from Monash University. This comment comes from Neville who is still in Paris working on the IPCC Report.

Dr Robert Colman, Lead Author, Chapter 8: Climate Models and their evaluation. Research Scientist, Bureau of Meteorology Research Centre.

Professor Andy Pitman, Lead Author Chapter 8: Climate Models and their evaluation. He is from Macquarie University and an expert in climate modelling.

Dr Ian Allison, Lead Author Chapter 4 Observations – changes in snow, ice and frozen ground. Antarctic Climate and Ecosystem CRC and Australian Antarctic Division.

Dr Ian Watterson, Lead Author on global climate projections of IPCC WG1 report. Ian works on climate impacts and risk for CSIRO Marine and Atmospheric Research.

Professor Will Steffen, Pro Vice-Chancellor (Research), Australian National University.

Dr Leon Rotstayn, Principal Research Scientist, CSIRO Marine & Atmospheric Research. Leon’s work on the regional effects of increased Asian particle emissions was the subject of some discussion within this IPCC paper.

Dr Graeme Pearman, Honorary Research Fellow, Monash University and spokesperson for the Australian Academy of Science (AAS).

Dr Mike Coughlan, Head of the Bureau of Meteorology’s National Climate Centre.

Dr Nathan Bindoff Coordinating Lead Author, Chapter 5: Observations – oceanic climate change and sea level. Antarctic Climate and Ecosystems CRC/University of Tasmania/CSIRO.

Professor Kurt Lambeck, Professor of Geophysics at the Australian National University (ANU) and President of the Australian Academy of Science.

"This intensive review of the past five years' sciApril 3, 2009dwide and confirms what we already know. We have now lost five years that could have been used in implementing remedial actions."

Professor Neville Nicholls, Lead Author, Chapter 9: Understanding and attributing climate change and climate scientist from Monash University. This comment comes from Neville who is still in Paris working on the IPCC Report.

"I was disappointed that after more than two years carefully analysing the literature on possible links between tropical cyclones and global warming that even before the report was approved it was being misreported and misrepresented. We concluded that the question of whether there was a greenhouse-cyclone link was pretty much a toss of a coin at the present state of the science, with just a slight leaning towards the likelihood of such a link. But the premature reports suggested that we were asserting the existence of much stronger evidence. I hope that when people read the real report they will see that it is a careful and balanced assessment of all the evidence."

LISTEN TO NEVILLE NICHOLLS SPEAKING IN ADELAIDE on Mon 5 Feb 07

Dr Robert Colman, Lead Author, Chapter 8: Climate Models and their evaluation. Research Scientist, Bureau of Meteorology Research Centre.

“There have been significant advances in climate models since the last IPCC assessment report – they now have higher resolution and include more climate processes than before. They also do a better job representing the present climate. For example patterns of temperature and rainfall as well as past climate changes that we have observed through the instrumental and palaeo record.

There is also better understanding of some fundamental processes controlling global warming, such as expected increases in water vapour (itself a strong greenhouse gas). We now have greater confidence in the way models handle this, which increases confidence in their projections of climate change.

Model improvements have also contributed to the increased confidence that humans are responsible for most of the observed warming over the last 50 years. This is because models are unable to duplicate the observed warming if they include only natural features like volcanoes and solar changes, but agree closely if greenhouse gas emissions are included.”

LISTEN TO ROB COLMAN SPEAKING IN MELBOURNE on Sat 3 Feb 07

Professor Andy Pitman, Lead Author Chapter 8: Climate Models and their evaluation. He is from Macquarie University and an expert in climate modelling.

"Climate models have improved considerably over the last decade and in particular the last five years. They can reproduce the observed climate very well. While our knowledge of global warming does not rely on models, projecting how the climate will change in the future does and these models are now clearly skillful enough to firmly underpin the warming scenarios used by the IPCC. There are remaining uncertainties of course, but these are likely to mean we are underestimating the amount of warming. More concerning is the projected rate of future warming and the likelihood of abrupt changes which may be underestimated by the current models we use."

Dr Ian Allison, Lead Author Chapter 4 Observations – changes in snow, ice and frozen ground. Antarctic Climate and Ecosystem CRC and Australian Antarctic Division.

"Global sea level is currently rising at a rate of about 3 mm per year (equivalent to 0.3 m per century) and the IPCC Fourth Assessment Report shows that almost half of this comes from additional water added to the oceans from the melt of land-based glaciers and ice sheets - the rest comes from thermal expansion as the oceans warm. There is evidence that the rate of melt of mountain glaciers, and perhaps also of the Greenland ice sheet, has increased in the last decade or so. Glacier melt and sea level rise as a result of global warming will continue for many centuries, leading to a cumulative sea level rise with societal impact. Globally, one hundred million people live within about one metre of present day sea-level and they will feel the impacts of rising sea-level through changes such as increases in intensity and frequency of storm surges, more erosion, loss of important wetlands and mangroves and coastal ecosystems such as coral reefs. In many dry climates regions, glaciers provide water for agriculture, community water supply, hydroelectricity generation, etc. Disappearance of glaciers will affect the seasonal timing of water availability with consequent socio-economic and ecosystem impacts."

Dr Ian Watterson, Lead Author on global climate projections of IPCC WG1 report. Ian works on climate impacts and risk for CSIRO Marine and Atmospheric Research.

"Projections of future climate change made by scientists have been largely based on numerical simulations of climate under a range of future scenarios of rising greenhouse gas concentrations. Results of 23 climate models from 11 different countries, including Australia, have been analysed for the new IPCC report. A global warming rate of 0.2 degrees per decade or more is likely to continue through this century. Australian temperatures are expected to rise by typically 3 degrees in 2100, although larger or smaller increases are possible. For the low to middle latitudes of both hemispheres, the models simulate widespread decreases in rainfall and cloudiness. Most models simulate decreased rainfall for southern Australia. The findings are largely consistent with the TAR, but are made with increased confidence.

Thousands of physicists, mathematicians, scientists and computer engineers worldwide have devoted much of their careers to the development of numerical models that now simulate the weather and climate system in marvellous detail and complexity (explore, for example, www.gfdl.gov/products/vis/gallery). Hundreds have worked for several years on the new simulations (see www-pcmdi.llnl.gov/ipcc/about_ipcc.php). These scientists receive limited recognition but have the satisfaction of seeing the fruits of their labour used to help guide both our day-to-day activities and, increasingly, the future of our planet."

Professor Will Steffen, Pro Vice-Chancellor (Research), Australian National University.

"As usual, the IPCC has done an excellent job of capturing the main advances in climate change science over the past several years. There is no doubt that the Earth is warming, and that many other associated changes in climate are now observable at the continental and global scales. And it is becoming equally clear that human activities, primarily the emission of greenhouse gases, are the main cause of the observed warming trend.

The focus now needs to turn even more strongly towards understanding the dynamics of the climate system through the rest of this century and beyond. What feedbacks in the climate system could accelerate the rate of warming, or could slow it down? What abrupt changes could be triggered as the warming continues, or what surprises might be in store for us later in the century?

Ironically, one of the best ways to tackle these difficult questions for the future is to look into the past. The last decade has seen a revolution in the paleo-environmental sciences, some of which is reported in the IPCC assessment. The planet is capable of behaviour that could severely stress modern civilization, and it is essential that we know whether human influences on climate could trigger such behaviour in the future.

Given that the climate will continue to warm for at least the next few decades, some impacts are unavoidable. Adaptation to these impacts is no longer a question of 'if', but of 'how'”, 'where' and 'how fast'."

Dr Leon Rotstayn, Principal Research Scientist, CSIRO Marine & Atmospheric Research. Leon’s work on the regional effects of increased Asian particle emissions was the subject of some discussion within this IPCC paper.

"New simulations with the CSIRO climate model suggest that increasing rainfall and cloudiness over northwest and central Australia in recent decades is due to the "Asian haze", rather than greenhouse gases. The effect occurs because the pollution haze cools the Asian continent and nearby oceans, and thereby alters the delicate balance of temperature and winds between Asia and Australia. Decreasing Asian pollution in the near future could reverse the effect and lead to a loss of rainfall over northern Australia. Senator Heffernan and others have argued that Australia should move its agriculture north in response to climate change. It is essential that we base big decisions like this on sound climate science, instead of simply assuming that future trends will be an extrapolation of recent trends."

Dr Graeme Pearman, Honorary Research Fellow, Monash University and Spokesperson for the Australian Academy of Science (AAS).

"This new IPCC data strongly suggests that for large parts of Australia south of 30 degrees, the prognosis is about loss of rainfall and as a result of the higher temperatures, loss of available water. That’s not to say that the present drought is definitely due to climate change, but what we are seeing is evidence that this kind of change is more likely to be the future than anything else. In the north of Australia the anticipation will be for loss of rainfall in the winter periods and higher evaporation which affects available water.

There is also evidence that the warming throughout east Asia has not been as fast as it would have been otherwise probably due to the effect of particles from forest clearing and industrialisation. That differential may be responsible for some regional changes in the circulation of the atmosphere and that’s what we believe may have caused the increased rainfall in north west. Australia. There was some discussion about whether that is the way of the future for the north but there remains some doubt, and this has implications for the discussion on whether it is feasible to move agriculture to the north."


Dr Mike Coughlan, Head of the Bureau of Meteorology’s National Climate Centre.

"I think that Table SPM-1 has some very 'sobering' messages for Australia. We can already relate very closely to the upward trends in warmer days and nights, areas affected by droughts and so on, all of which trends are assessed as likely or more likely than not to have been influenced by human activities and all of which are virtually certain to continue."

Dr Nathan Bindoff Coordinating Lead Author, Chapter 5: Observations – oceanic climate change and sea level. Antarctic Climate and Ecosystems CRC/University of Tasmania/CSIRO

"The observed widespread warming of the atmosphere, ocean, together with the ice mass loss make the conclusion that it is very likely that it is not due to known natural cause alone. Most of the observed increases in global average since the mid 20th Century is very likely due to the observed increase in greenhouse gas concentrations.

I find the these conclusions from the attribution section extraordinary. They just point to a coherent pattern of change in earth, and the projections just show what we can expect in the future."

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Footnote: Read the thoughts of Lead Author Professor Neville Nicholls writing in Paris in the leadup to the release of the AR4 Report in our new Science Blog section.