Well, people can put up a zillion stories that sound credible. "I take this and this and this" and look: we deny what science has to say. The certainty that the Earth is warming because of us is about as certain as HIV causes AIDS or that indeed 6 million Jews died in WWII. And yes: there are even some scientists who deny those facts. One Holocaust denier is in jail byw and he is a historian.
Most people logically follow what a majority says about AIDS and Jews, not only because denying these things is rather painfull. But the scientific proof is about as strong with global warming.
Deniers rarely if ever make an attempt to come with an explanation for the warming that they can backup with a good scientific study, with statistics and have it peer reviewd.
Saying "it is natural" because it has always happened is about the same as saying that the deadman with a knife in his back died because of natural causes, because people always have died because of natural causes. Co2, CH4, CFC's etc are the knife in this example I often use. A knife deep in your back is about as sure to kill you as those greenhouses gasses are KNOWN to warm the planet.
Now why do we believe (some of us) deniers who do not study a thing, who do not deliver any scientific paper to Nature, Science, or JGR or GRL? I know something about psychology. In this case, my comparison is the one with smoking. If a message is too dreadfull to hear and the problem seems to be something you THINK you cannot deal with, you deny the problem so you do not have to work on it and fix it. You can live happily ever after. Now the chance that smokers die of lungcancer is 15%. 92% of all people who die of lungcancer have smoked in their lives or are active smokers. If that isn't enough, you have heartdiseases, strokes (highly correlated with smoking). Than you have COPD (incurable and deadly) that causes many deaths in smokers, throatcancer of course. Less know problems is that you have a 66 fold increase in getting rheuma and you have a much bigger chance (very strong correlation) of having lower back pain.
Now: most smokers do not know these facts. Because not all of them are well know and some of them they do not want to hear.
The comparison with global warming is the same in the sense that the outcome of global warming with no effort on a global scale is about as bad as keep on smoking for the individual. The chance that global warming will kill billions of animals and millions of people is very likely in this century.
So we have to act now. But we are afraid of what we will lose and we do not look at what we will win. We are afraid of.....an economic disaster. We seem to be addicted to having things, being able to do things that we do know and we are afraid that we will lose these things. Like a smoker does not think about cleaner lungs, a longer and healthier life. remaining a parent longer for his kids and grandchildren etc No, he is afraid of the small kick he will miss the first months or so. And thus denies of what is wellknown about smoking.
There will be those, who have big money know with an oil fueled economy who will loose their current, wealthy position if we turn into a green society.
There is many, many evidence of oil companies doctering documents, supporting a few "scientists" who come up with a different version of their story with always the same conclusion: do not change a thing...first it wasn't true, than it was a bit true, now it is true, but not harnfull and even benificial!
Global warming is not a belief. Not a religion. As it is science, there does not exist 100% certainty. There is no 100% certainty in science, there is only probability. Above 95% probablity as accepted as a fact in science. I can lookup the numbers, but I think it is about 98-99% sure that the only explanation of the current temperature trend is that it has a human cause. In science, this means that global warming is a fact.
Besides: there is not a single, countering theory that has any evidence that explaines the current warming. Look it up, try to find any peer reviewed scientific report/artcile/study or whatever that can explain past and current temperature trends and bakc it up with sound science. There is none.
Those who do not "believe" it: why do you not believe thorough scientific research by those who hnot only have completed a University education on the topic (this does not have to mean a thing) AND have done extensive studies in the field. If you look at your thoughts: why do you believe what people who are not active in the field and do not study Global warming, climate change or whatever, have to say??
Do you think this is simpel or do you think it is complex (or over shoot: it is too complex...)?
Boa noite a todos,
J.S.