For someone who is not an expert it is quite simple. Trust the experts. More specifically, trust the general consensus of the scientific community.
All of the figures, plots, and graphs are not enough to truly understand the problem. Data can be formatted to backup almost any claim. You have to dive deep into the topic to understand enough to come to your own conclusion. So unless you plan on getting a PhD, trust those who already have. And do not trust individuals - they can be purchased. Rely on conclusions that have been presented, discussed, and argued by the scientific community thereby resulting in the acceptance of said conclusion.
And one last point. Ignore articles posted in places such as Slashdot. Rely on articles posted in reputable scientific journals. All of the newsfeeds that repost these things filter out anything they do not want you to see. Bogus papers will be posted but the numerous rebuttals showing that the paper is bogus will not. In essence - you are lied too. So go to the original source where crap is called out for what it is.