Yes. Yahoo Answers is an appropriate format for scientific issues like global warming.
However, there are difficulties, as there are in any format, when the issue raises strong emotions. I add a quote from Tomcat here because I think it is vitally relevant to what you are asking:
'There are basically two sides on this subject, and this is a very important subject because the theory of global warming associates damaging global climatic change with the actions of peoples ordinary lives. If people are to be implicated with destruction of the future generations climate, many people will do all they can to ensure that their view on the topic is heard'. Tomcat 2007
To summarize it is not only the importance of the issue itself, it is that our actions today will be judged by future generations. So for reasons stated above the subject is a very emotive one. Both views feel passionately about the topic.
Most platforms which are used to raise issues, such as YA will attract non expert and unsubstantiated views. This can be exceptionally frustrating, particularly when factually incorrect answers are selected/voted as being correct. However,
we do have tools to moderate the answers we receive to some extent ourselves, see the Community Guidelines (CG). It is up to us as individual as askers and answerers and as a community to ensure we use those tools effectively.
I suggest it is in everybody's best interest to work together, so that the following steps are taken by ALL people.
1) As a community, we do not accept contraventions of the Community Guidelines. This includes questions and answers that name an individual, that are rants, flame starters, hate speech, spamming, doing harm; 'this includes not misrepresenting yourself or giving advice in a way that might cause someone harm.' YA CG
2) Take mass community action, within the Community Guidelines on those we suspect as cheating by reporting them, not calling them out. Whilst multiple accounts are permitted, if they are used for point gaming, voting, to abuse Community Guidelines or to 'post content for the sole purpose of gaining points or soliciting others for points is not permitted. Posting filler answers to a question in an effort to be first to answer, or copying and pasting other members’ answers, are also forms of cheating' CG YA
3) Yahoo Answers is not an expert site, there are those who are expert in their fields who give their time and expertise freely (Thank you experts). As askers we need to be certain as to whether we are asking for opinion or facts and indicate this on the question itself. The really IMPORTANT line from the CGs here is: 'When you post an answer, it must attempt to answer the question being asked' otherwise you are in violation of the CGs.
4) In the heat of the debate, we can all get carried away and forget to treat each other with courtesy and respect. We need to be mindful that the intention of the site is about sharing information when we ask or answer. Manners are a way of making a situation more comfortable. Again, it is against CGs to be discourteous.
'What is a Troll
A "troll" is someone who intentionally and persistently posts inflammatory messages about sensitive topics to bait users into responding or provoke a confrontation. We also consider people to be trolls when they persistently misuse product features such as the ratings system to negatively target others' YA CGs
Finally, in answer to your question, yes, it has it's problems but in my opinion it IS an appropriate format.
Secondly, I disagree, Y!A is relying on the community to moderate the questions. WE, THE COMMUNITY, ARE ALLOWING MISINFORMATION TO SPREAD, by not reporting violations of community guidelines.
'All that is necessary for the triumph of evil is that good men do nothing' Edmund Burke