At its base, climate science is a straightforward piece of data gathering on the weather. Thousands of scientists spend their waking hours measuring and monitoring the likes of ice cores, ocean temperatures, sea levels, growth rings, and elements in the air and water. They crunch the data and produce the graph.

The problem is they ran smack bang into the fundamentals of the capitalist era and 100 years of exponential exploitation of the earth's resources in the pursuit of growth. Capitalism is built on growth; and Australia is tying itself in knots right now over how to boost growth back to long-run levels considered essential for a humming economy. This is where science meets vested interest.

For scientists, the question becomes, do they buy into the fight. Increasingly, the answer appears to be yes. Scientists, who for decades assumed facts would win the day, are now finding themselves forced into advocacy to confront the loudmouths who have elevated beliefs to the same level as facts.

This is the context in which 11,000 scientists have this week declared a climate emergency.

One of the lead authors on the paper published on Tuesday and signed by scientists around the world, University of Sydney ecologist Thomas Newsome, produced a YouTube video to accompany the release.

The video has a six-point manifesto for change: replacing fossil fuels with renewables, reduce climate pollutants such as carbon, stop land clearing, reduce meat consumption, reverse the obsession with growth and put the brakes on population growth.

For all they are backed by science, these are undeniably politically charged solutions. And for all that you might well support Dr Newsome's manifesto, it demonstrates the situation in which scientists have found themselves - advocates on one side of a divisive political argument.

You might also have noticed the extent to which the media is entering the argumentative fray, the Murdoch press continuing its long and strident campaign on the side of denial, and now the Guardian declaring a campaign under the banner "It is time to act". Even the ABC has added a data slot to its news bulletin each night, graphing the rise in temperature in different and obscure parts of the country. The ABC might be sticking to the data, but the slot is subversive.

The science of climate change has been caught up not only in advocacy but separately, climate change itself has bizarrely become something you either "believe in" or don't, as you might believe in a deity, or the power of love.

Anyone tempted to start a sentence about climate change with the words "I believe" (or not) would do well to remember that disbelief is not the same as scepticism. Every thinking person should be sceptical, question the dominant paradigm and ask questions when fed a fact or a story. This is something children do better than adults. Tell a child that if they touch the electric fence it will give them a shock and they will test the theory. But the process of growing up is learning how to short-circuit this process by learning how to distinguish between good information and bad. Your choice is to take a higher degree in climate science or listen to the judgement of those who have.

If you're looking for optimism in this most crucial of challenges, there are signs that the government, for so long obstinate in the face of calls for greater action to mitigate the impact of climate change, is starting to listen. $1 billion has been committed to the clean energy regulator, a panel of energy experts has quietly been formed to assess the best way for Australia to meet its international emissions obligations, 22 per cent of the nation's energy now comes from renewable sources, and Australians are among the most enthusiastic installers of renewable power in the world. Perhaps the momentum will take hold.