While nothing in our experience compares with the industrial scale of the Nazi killing systems, how much longer can we continue with our pretence that that our unthinking consumption will not create a genocide of even greater magnitude?

Already in Australia, since 1788 we have destroyed over 50 species of birds and mammals and numerous Aboriginal tribes.

But even that level of destruction will be quickly overtaken by the impacts of our rapidly deteriorating climate.

The gift of 10,000 years of stable climate on this glorious planet is over.

With over six billion people now occupying every available niche, we no longer have the luxury of denial.

Germans found it possible to deny the existence of the incinerators.

John Howard remained a climate sceptic to the end.

Kevin Rudd may believe he can do deals with the climate. But our climate is not listening.

Climate change is accelerating and taking with it our agricultural lands, our rivers, our birds and mammals, and increasingly more of our people.

The heatwaves, the fires, the floods, the cyclonic winds, the droughts, the food shortages, the mass migrations and, yes, wars, are only just beginning.

If we want to understand the wilful blindness of a nation, we only have to look in our own backyard.

Mike Clancy, Holder

CO2: Proof is at hand

''Truth hath the property that it is not so deeply concealed as many have thought; indeed, its traces shine brightly in various places and there are many paths by which it is approached. Yet it often happens that we do not see what is quite near at hand and clear''.

De Motu: Galileo Galilei (1590).

A recent conference of climate change deniers in New York contrasts with the scientific summit in Copenhagen which concluded that the worst-case IPCC scenarios are being exceeded: '' ... these parameters include global mean surface temperatures, sea level rise, ocean and ice sheet dynamics, ocean acidification and extreme climate events.