The sample size is irrelevant in this particular conversation unless you would be able to clearly define the FAILURE of that sampling to accurately reflect the total population.
Which, if you would like to do, you can actually do so. There are SEVERAL independent and unrelated methods of assessing scientific agreement on the topic and all of them (remember they are INDEPENDENT METHODS AND UNRELATED) keep coming up with about 95+% agreement among the professionals.
Now, of course Science ISN'T DONE BY CONSENSUS. But consensus shows where the majority of the professionals are leaning.
Let's say you went to Vegas to bet some money. You decide to go to the sports betting areas to bet on an NBA basketball game (or whatever). Would you go in without knowing anything about basketball or even the teams and place your bet? No, you'd learn about the game and you'd listen to odds makers and the professional coaches and sports authorities.
That's what I'm talking about here. Repeated studies (which you can look up) have found this consistent figure. Even if it is not 100% perfectly accurate it shows that it is at least >50% of the professionals feel this is a true fact (AGW).