By Neville Nicholls, Monash University
Maurice Newman, chair of the Prime Minister’s Business Advisory Council, has called for an independent review of the Bureau of Meteorology’s climate data, following a stream of recent articles in The Australian newspaper attacking the Bureau’s methods.
I support his call for an open and public inquiry into the Bureau’s climate data and the techniques that the Bureau’s scientists have used to reduce the influence of changes in instrumentation, exposure, and weather station location on its climate records.
I support it because I don’t think the Bureau gets enough opportunities to demonstrate to the public its scientific integrity, hard work, and valuable results.
Free and open information
A public inquiry would provide the Bureau with the opportunity to point out that all of its archived climate data are accessible (for free!) by anyone in the world with an internet connection.
It would also allow the Bureau to demonstrate the scientific methods it uses to reduce the influence of problems that complicate the evaluation of historical climate data. All of the original data remain available to anyone who thinks they can do a better job (and some groups, such as Berkeley Earth, have done exactly this).
The attacks on the Bureau data appear to have been triggered by Australia’s record warmth in 2013. This record warm year doesn’t sit well with the meme of “global warming has stopped”. Despite the attacks, there is a mountain of evidence that the Bureau is completely correct in its assessment of 2013.
The graph below illustrates just one piece of this evidence. The red line shows the Bureau’s average annual Australian temperature, illustrating the fact that 2013 was the warmest year on record. In blue, I have plotted Australia’s average annual lower atmospheric temperature, estimated from satellites (rather than with surface thermometers as used to produce the Bureau’s graph).
The blue line comes from freely available data compiled by US climatologists Roy Spencer and John Christy. This temperature record used to be enthusiastically promoted by some people, when the data first appeared in the 1990s and appeared to show no warming. Yet after Christy fixed a few problems in the processing of the satellite data, the data for Australia now show even stronger warming than the Bureau’s thermometer data since 1979.
The Spencer-Christy data confirm that 2013 was the warmest year on record over Australia. And the close correspondence between their temperature estimates and the Bureau’s own temperature record should convince anyone with an open mind that the Bureau does an excellent job of handling climate data, and that its temperature record is accurate and reliable.
So I’m sure many other climate scientists would also support an open, public inquiry that would allow the Bureau to showcase the reliability of its climate records.
Further evidence of Australia’s continued warming is shown in the graph below, which plots snow depths at Spencers Creek, near Thredbo (data are available here). The red line shows the maximum snow depth each year; the dotted red line shows the gradual downward trend in maximum snow depth over the past 60 years; the blue line shows the snow depth at the start of October each year; and the dotted blue line shows the strong decline in these spring snow depths.
This clearly shows that the Australian snow season is shortening in response to warming. But does this matter? Who cares if Australia is warming and the ski season is getting shorter?
Those of us in Mr Newman’s generation should definitely care, because it is not just average temperatures that are increasing. Heatwaves are
also becoming more frequent and intense. Record heatwaves across southeastern Australia in 2009 and 2014 led to large increases in the number of deaths, particularly among those of us of advancing years.
Luckily, the heatwave forecasts that have been trialled by the Bureau of Meteorology mean that we should be able to minimise the number of deaths caused by future heatwaves.
Nowadays, the Bureau’s five-day weather forecasts are more accurate than the one-day forecasts available when Mr Newman and I were young.
Governments around the world, with climate scientists and health specialists, are developing improved heatwave alerts in response to the threat posed by global warming. They couldn’t do this without the help of the improved weather forecasts now provided by national weather bureaux.
One obstacle that stops these heatwave alerts from saving more lives is complacency about the increased threat, as well as lack of knowledge about what to do when a heatwave alert is issued.
Not only would Mr Newman’s inquiry help to warn the public about the increasing threat of heatwaves, but it would also provide the Bureau of Meteorology with a rare opportunity to demonstrate how its improved weather forecasts can literally save lives. If that comes to pass, Mr Newman would truly have done the nation a valuable service.
Neville Nicholls has received funding from the Australian Research Council for climate change research, and has been involved in the preparation of scientific assessments by the Intergovernmental Panel on Climate Change. He was employed as a climate researcher in the Bureau of Meteorology from 1970 until 2005. 25 years ago he initiated Bureau efforts to reduce the confounding influence of problems in the historical climate record caused by changes in instrumentation, exposure, observing techniques and station location.