That's why there is peer review of scientists of this particular area and not a quorum of random people deciding if they believe this study or not. While I think peer review is certainly not perfect.
The number of studies which could not be published in a well reviewed journal and later on were proven right after all is relatively low (There are some studies on that).

In the current climate debate we can see a number of things though:

a) Most deniers use either studies which were never published anywhere
b) Or they wrongly interpret existing studies
c) Or they do some wacky experiments and claim they work fine

If you don't believe in climate change I advice you to check out the videos of Potholer I linked above, he has a very scientific stance on the things but he pretty much shows clearly which side in this discussion is currently far ahead.

I am not saying that it is impossible that one day some smart guy finds out we were wrong all along, but for the time being man made climate change is the state of the art and until now no one had enough scientific proof to prove it otherwise.