I’ve been refreshing my climate change slides for a couple of forthcoming workshops – one with NHS directors and the other for staff from a leading international engineering firm. And it’s taking me deep into the murky world of the blogosphere.

The scientific consensus on climate change is clear. The scientific community is somewhere between 97 and 99% certain that man-made carbon emissions are responsible for a significant change in climate and, if this continues, the impacts on the earth will be huge. The political world is waking up to this consensus, and with the US, Australian and Chinese leaderships really leaping on board, there is a great chance of a significant international agreement in Copenhagen later this year.

But in a huge number of blogs and comments on forums and newspaper articles, these scientists, politicians and green activists are labelled “warmists”, “alarmists” and “socialists” who are trying to curtail free enterprise and raise taxes (the greens retaliate with the loaded term “denier”). Therefore the scientific consensus must be a conspiracy with research funding only going to those who toe this political line (ignoring the fact that the scientific world has been struggling to get politicians to take note of climate change for decades).

So why are all these people convinced that there is a great swindle going on? Well…

1. Climate change really does threaten a lot of vested interests. From the fossil fuel executive to the couple who like their city-breaks to the man proudly polishing his SUV every Sunday, somebody is telling them they can’t do what they want to do.

2. The science is complex once you get past the basics, leading to apparent anomalies which can be seen as a case against – I know people who are convinced it isn’t happening because we had a two-week cold snap in the UK this winter, when there was a heat wave in the other hemisphere at the same time.

3. There is no quality control in most of cyberspace and no barrier to entry (many of the “deniers” lack even a degree level qualification in a related topic). Discredited ‘facts’ keep bouncing back from repeated rebuttal, conspiracy theories thrive and falsified data and graphs magically appear.

So, the moral of the story is: listen to the experts – those who have published peer-reviewed scientific papers on the subject – and never, ever google “climate change”.