Merely my observations. A few common fallacies used when debating.
1) Quote mining:
Quoting famous scientists, authors, celebrities, the man on the street e.c.t in such a way to advance a point. Generally this is ill-advised as essentially anyone can be made to support any proposition by skilfully quote mining them, i.e taking the person out of context. Typically quotations are judged on how profound they sound, rather than actual utility. Instead of quotations which might be appropriate in an English literature exam, I would recommend a reference instead. Here is a webpage that gives an exemplar method of citation <http://www.nwmissouri.edu/library/CITING/cbe.htm> Obviously it is not expected in a forum setting, but a URL to a journal article is not too much to ask.
2) Appeals to conflict of interest or conspiracy
In the first case, such an objection could be justified. However it is not the case simply to assert a conflict of interest without justification. All scientific papers and journal articles are plagued by this phenomena, although the peer review process tends to minimize the effect for high impact journals, so be weary of open access, or articles not submitted for peer review. Certainly using conflict of interest as a way of simply discarding a journal article without even reading it, is completely inappropriate. This however, generally only applies to situations where confirmation bias is reasonably low which boils down to the peer review system once again. In the case of conspiracy of suppression, there are statistical means to implying publication bias for instance, however it is all too easy to assert a conspiracy without evidence, because by definition a conspiracy theory is un-falsifiable. Anything that can be applied without distinction to any publication is not a useful determinant of validity.
3) Giving undue weight to individual scientists.
The same applies to giving undue weight to a single scientific study. An argument from an individual scientist given to the public will seem convincing regardless of the position, usually because the scientist is arguing from a position of knowledge, whereas the public come from a position of relative ignorance. Thus appeals to the general public, and media are no substitute for the peer review process and the opinions of other scientists, and colleges in the community. Now, by the same token one should not simply dismiss the opinion of a scientist because he or she disagrees with most of his or her colleagues. However new and innovative ideas would still be examined by said colleagues. This is the concept of reliability, and repeat-ability.
4) Poor referencing, often to blogs or media articles.
Now of course, the reference should suit the purpose. It is fine to link to a newspaper that objectively reports on a phenomena in science; i.e scientific journalism. However, blogs and newspapers are not the place for original research and should never be referenced to in the context of a review of evidence (or indeed a 'systematic review' in the case of a paper published examining all the relevant evidence for a particular concept). This holds true particularly if the concept or idea conflicts with current understanding. For instance, I could get away with talking about Newtonian mechanics by referencing to a informative website, or the general media - I wouldn't be expected to go back to Newton's principia. However in the case of paradigm shifting ideas, I would be expected to provide a more appropriate reference.
5) Ad homenin attacks, tone critisms.
Often these just annoyingly get in the way. In the first case, an ad homenin attack is critisising a persons character with the aim of refuting their idea. As always, an idea or concept is true regardless of the author. In the second case, tone criticisms are a specific example of an ad homenin attack. I.e attacking the presentation of an argument, rather than the argument itself. That is not to say tone isn't important, or cannot be critsised, but shouldn't be done so under a veil of refuting a concept or idea.
6) Arguments from ignorance - the big one.
Or arguments for intuition. Allow me to construct an analogy. If you push an object, it moves faster. If you push an object going pretty fast, it goes even faster. So if you push an object moving at the speed of light it will go faster surely?! This is a simple one that most people should be aware of, but counter-intuitive concepts are extremely pervasive in science. For instance, try and explain to me concisely why moving faster on a bicycle increases stability, and why a person might fall of if they were to move too slowly? Or perhaps, why drinking alcohol actually lowers your body temperature not raises it. Or why the sea ice in antartica is growing despite a generally warming southern ocean? I think I have made my point. Just because something is counter intuitive does not mean it is 'obviously' wrong. I would be weary of even using the word 'obvious' at all. But before making an argument from intuition, please consider how realistic the view is, that no climate scientist would have thought about such an 'obvious' objection.
7) Fitting evidence to the conclusions.
It is possible to tell sometimes when people are doing this. Please, before making an argument consider whether you have checked a reasonable body of evidence. And I don't mean 'from both sides of the argument'. The idea that simple dichotomies exist in climate science is incredibly naive, a more accurate reality is different models/methods producing different results that have different interpretations.