Actually, I can say that. He stated that the majority were dubious at best. I displayed the findings that a majority of those papers stated either complete rejection of the theory, or were unwilling to call it either way. That would be dubious- having doubt or uncertainty in their findings.
An important thing to remember that it is far easier to prove existence of something, whether it be the influence of people on the climate or the existence of unicorns. In order to infallibly disprove existence of something, a scientist needs to be essentially omniscient- how else could I prove that unicorns do not exist, unless I had knowledge of the entire Universe? Furthermore, in order to say Unicorns have never existed, I would then need omniscience of the entire universe for all of time. Obviously, it is impossible for me to infallibly disprove unicorns' existence.
Modern science must operate using facts to disprove something beyond reasonable doubt. And this means that it only takes one unclear study, one off-beat piece of data, or one reasonable counter argument, regardless of whether these things are valid, to make a good scientist say "Woah there!".
That 48% which did not take a clear stand most likely found some abnormality in their findings- something they were unsure of or something that they felt deserved further investigation before making a conclusion. These skeptical 48% are practicing science in its best form- analyzing data and addressing all possible avenues of though before making a conclusion.
Do I believe man had something to do with climate change? It's possible, I haven't been convinced either way. But regardless of your views, you need to realize that the plurality of scientists in this case say that it is too close to call. In my opinion, that should cast serious questions on both the 45% who say there is clear evidence that man is the cause, and also the 7% who say that man is not the cause. Think about it- these sort of percentages would result in a hung jury if this war a court trial, which operates on similar principles, so why should we call in the decision on climate change? We need to stop dividing into camps for war and accept that being undecided is a perfectly reasonable conclusion(or lack thereof for that matter).