What I mean by opinion is the degree of your argument, that is, if you contest the earth is heating up there are no opinions, if you contest it's man made then we would be able to discuss it with the vast weight of evidence on my side.
Seriously read the stuff I wrote and links, tell me what you conclude?
When I was in high school in the 60's, "most" climatologists predicted global cooling - that we were headed toward another ice age, in fact.
If the climate models that are referenced to support projections on continued warming based on human activity are accurate, why can't those models and their creators predict what the weather will be tomorrow?
Moreover, once the man made global warming crew got political support, dissident scientists found that they could not get their views published. There is now in fact a huge "global warming" industry with a vested (financial) interest in dismissing other explanations for the current warming trend, or the current appearance of an unprecedented warming trend.
The paradigm of science as a totally objective enterprise that builds incremental understanding of the natural world free of political and consensus prejudice was shattered by Thomas Kuhn in his "The Structure of Scientific Revolutions".
Remember the War on Cancer, funded by Nixon, and resulting in the fallacious view that most cancers were caused by viruses (see Robert Gallo's research in the 1970's and 1980's)? That view also enjoyed support among a large consensus of cancer researchers for years. But it is now acknowledged to be false.
I don't know that the same factors are at work in support of the man made global warming majority view. But I do know that dissidents can't get published, and that climatology as a science is far from mature.