Ray, there are several points you make that I'm "missing"!
It strikes me that you both agree with, and disagree with the concept of the reality of global warming, all at the same time! That is truly cool, only to be expected from a gentleman who is photographed sitting beside tigers.
Rob.
The explanation lies in the ethical dilemma, 'when is a lie justified?' This is similar to the ethical dilemma of photographic manipulation. If the intention and purpose of the photograph is to accurately record a scene for journalistic or forensic uses, then manipulation of the original photographic recording, which is equivalent to lying, is obviously unethical.
Likewise, if the purpose of climate-change research is simply to understand the climate change processes at a theoretical and unbiased level, then exaggeration of the degree of certainty about the processes is unethical, unless such exaggeration (lies) can be justified in relation to another issue.
In the case of photography, manipulation can be justified for 'fine art' purposes, which might attempt to entertain, inspire, tell a story, create an enigma, express the photographer's personal feelings, etc.
In the case of climate science, any certainty about the disastrous consequences of rising CO2 levels is a lie from a purely scientific perspective. However, from a broader perspective of the survival of future generations who might be confronted with a disastrous depletion of fossil fuel resources, any lies which motivate us to prepare in advance for such 'over-exploitation' of resources, might be justified.
One of the possible negative effects of being motivated to do the right thing through incorrect or biased information, is the inefficiency of the process. It would be better if people were able to respond to rational and sensible advice and objectives. However, the reality seems to be that most people are not sufficiently motivated by merely sensible and rational arguments. They need religious zeal. They need 'carrot and stick' inducements. They seem to need the fear of eternal damnation in Hell to get them to behave properly. Hope that's all clear?