Six steps to counter your friendly, neighbourhood climate change sceptic

Having spent the many years taking on climate change sceptics, I have found that the following works well:

1. Determine whether the person is a sceptic or a denier. A denier is someone who simply does not ‘believe’ that global warming/greenhouse gases/climate change is an issue.
2. If a denier then explain that there is no point discussing further as they are basing their argument on a ‘belief system’ rather than scientific argument. Once you explain this, you will find they suddenly become a ‘sceptic’!
3. If a sceptic, then explain the basic science that all scientists agree upon:
a. CO2 and greenhouse gases trap in the Sun’s heat and keeps us warmer than the moon. Explain that this was determined in the 19th century and mention that it was the French mathematician, Joseph Fourier who first identified this fact in the 1830s. The name Fourier usually impresses engineers and scientists! I also find it useful to explain that we experience the Greenhouse affect on any nights where clouds appear. In a cloud free sky, we have cold nights. When clouds appear, the water vapour in the clouds, being a greenhouse gas, trap in the Sun’ infrared heat and increase temperatures.
b. CO2 levels are increasing due to our burning of fossil fuels
4. Then go on to explain where there is dispute. That is over the increase in temperature and the speed with which it happens, specifically:
a. The ratio between CO2 increase and global temperature increase. Calculations done early in the last century suggested that a doubling of CO2 will increase temperatures by an average of 5 degrees celcius. Some scientists believe that this is too high, others that it is too low.
b. Increased plant growth may absorb more CO2
c. Increased cloud cover caused by a warming planet may reflect more of the sun’s ultraviolet heat or may trap in more of its infrared heat.
d. Reduction in ice cover will cause less of the sun’s ultraviolet radiation to be reflected back into space, thus causing increased warming
e. Melting of vegetation that has been frozen for thousands of years will release both CO2 and Methane, adding to those greenhouse gases and pushing temperatures higher
f. The sun’s activity may slow down, offsetting any increase in temperature caused by the Greenhouse effect.

By this stage, hopefully, you have allowed them to save some ‘face’ by accepting that there is dispute over the speed of warming but also started them on a journey to accept that, irrespective of these arguments, as we continue to increase greenhouse gases there will be a constant underlying warming of the planet.

I welcome any refinements, critiques of the arguments, etc. In particular if you do know of any credible scientists that question the basic science of greenhouse gases keeping our planet warmer than the moon then please let me know. ‘Deniers’ claim they are out there but I have yet to find one!