TONY EASTLEY: The head of the CSIRO, Dr Megan Clark has come out in defence of climate scientists and says there's absolutely no doubt there's a link between humans and climate change. She says the evidence of global warming is unquestionable and in Australia it's backed by years of robust research. She says climate records are being broken every decade and all parts of the nation are warming.
Dr Clark is speaking to environment reporter Sarah Clarke.
MEGAN CLARK: Look, we are seeing significant evidence of a changing climate. If we just take our temperature, all of Australia has experienced warming over the last 50 years.
We are warming in every part of the country during every season and as each decade goes by, the records are being broken. Our records of the '70s were broken in the '80s, broken in the '90s and we are also seeing fewer cold days. So we are seeing some very significant long-term trends in Australia's climate.
SARAH CLARKE: So given these observations then, what is your response to those who suggest that the planet isn't warming?
MEGAN CLARK: Well, I think we can certainly look at the long-term trends and any event here or there or a storm here or there really doesn't explain away what we are seeing in these major long-term trends.
We are also seeing consistency. I think the consistency between our temperatures, what we are seeing in our rainfall, what we are seeing in the increase of carbon dioxide and methane in our atmosphere and of course, what we are now seeing in our oceans.
So it is not just one measurement that is telling us. It is our observations and science that we are seeing in many areas being consistent.
SARAH CLARKE: So how much is manmade climate change then contributing to all of this?
MEGAN CLARK: We know two things. We know that our CO2 has never risen so quickly. We are now starting to see CO2 and methane in the atmosphere at levels that we just haven't seen for the past 800,000 years, possibly even 20 million years.
We also know that that rapid increase that we've been measuring was at the same time that we saw the industrial revolution so it is very likely that these two are connected.
SARAH CLARKE: So therefore what is your response to those sceptics who are saying that CSIRO and scientists who are witnessing these observations and talking about these observations, what is your response to them when they are saying that you are wrong?
MEGAN CLARK: Well, actually I think whenever we come into grips with a very complex issue as a society, every time we have done that, we should challenge and we do challenge and it brings us back to our observations. It makes us relook at what are we really seeing? It makes us ask those questions so I think challenge is simply part of coming to understand an issue.
But at the same time, plucking out a snow storm in the US or a flood in Queensland or a cold day somewhere and trying to use that to explain away some of these long-term trends, of course, we know is not the right way to do it.
I think I look at it in the same way, if you look at someone's bank balance and say the day after they got paid, gee they are looking pretty good and of course, you could never assess whether someone was in fact improving or deteriorating in their finances unless you actually looked at their balance over a year, over a few years etc.
So we can't use these small fluctuations, I think, to explain away some of these trends.
TONY EASTLEY: The chief executive of the CSIRO Dr Megan Clark talking to environment reporter Sarah Clarke and the full interview can be heard on our AM website. Just search in Australia for AM - ABC.
