Science doesn't happen by consensus. It happens by rigorous proof and verifiable, repeatable testing of a (hopefully null) hypothesis.
I think a lot of the replies are missing your point. Ok, first, the problems science tries to study are too big for any individual to crack on his or her own. So modern science is largely collaborative. And that collaboration is organised around a meritocracy of knowledge and achievement. So there is a hierarchy and expertise is key to that hierarchy. And that's just how it is, so yes, science DOES happen by consensus, starting with the student who learns from the teacher, and the teacher who learns from their teacher, on up to the masters who have the most skill and ingenuity and who are driving the science forward.
But that's not your point, and I think many people get stuck on this first truth, that science is a collaborative meritocracy, that it does operate by consensus.
But operating by consensus does not necessarily mean the results and theories are correct, that they are, in actual fact, true in the real world. That's the big difference.
So science has to operate by collaborative meritocracy (because the project is so big) but that does not mean that the results are actually true.
Now, given science's generally stunning success in many fields, we can generally assume that science gets it right. We have microchips and CT scanners and jet engines and so on. And that is a general point, we generally know science generally works.
But climate change/global warming is a specific field, a specific theory, run by a specific set of people.
And it is a lot like how the police force in general, operate on the principles of justice and service and protection, and generally we all rely on the police to help protect society, but that does not mean that any specific group of cops in a specific precinct don't have any, for example, institutional racism.
So here's the thing. When people counter, "there is a consensus" that really misses the point. For if there is reason to be sceptical of the claims of a particular field, the only way forward is to research those issues. It does not help to say, well there is a consensus, because consensus is merely an automatic aspect of the social practice of science in a meritocracy of collaboration, it does not answer whether or not the theory is correct.
Consensus because we got it right? or consensus because of an unnoticed systematic bias which happens when research goes down one path, and alternative hypothesis are starved of air and funding and interest, simply because they didn't look promising early on? and everyone has to compete for funds?
In that sense, consensus is not science (if by science you mean, is the theory actually correct in reality?)
Put it this way, "the police are a force that serves justice, therefore there is no racism in the police" -- that's just circular reasoning, and if someone answers that in reply to, "hey, is this police unit showing signs of racism?", and all you hear is, "there's no racism because the police are here to protect", then you'd likely conclude that that is just an evasive answer.
Science is run as a collaborative meritocracy, where consensus decisions are made, and that has nothing to say about whether a specific theory produced by particular scientists is correct or not in reality.
The other aspect to this is that laypeople are supposed to trust the science. Well, here we have the other issue that we are all human, and humans all have a psychology that is highly prone to bias and selfish needs. If you are a human being, that's you and that's me. There is something called "expert bias" where people can't see their own bias because they know themselves to be experts and therefore, less likely to be biased or swayed by anything non-rational.
And besides, science is done by human beings who need funding and prestige and need to build their reputations. And as humans, we all have principles, we all want to do our best, and do the right thing, and also, we are all fallible. Just like the police are there to serve justice but are also fallible. A scientists is certainly far more intelligent than a policeman, let's say, for sake of argument, but when it comes to integrity and/or bias, I'm not aware that anyone has a monopoly on being the most advanced in that area.
So what to do? Any scientist is probably more inclined to trust the findings of other fields, at face value, because they know for themselves that they live and work in an organised hierarchical social meritocracy which requires many years of study, and where reputation and recognition are highly meaningful. Whereas random Joe in the street might not understand this, yet that also makes random Joe less prone to the group-think which any science field may have fallen into, largely due to its collaborative consensus building process.
So yes, science does operate by consensus, and most science works, and also, consensus says nothing on its own about whether a theory is correct, and yes one has to be a scientist to appreciate the level of knowledge and the importance of the social meritocracy, and yes, Joe in the street does get to say, "well the priests keep saying Zeus/God/Global Warming is real, but I haven't yet seen anything to show that to be true."
For example, when experts show a graph that obesity rates are climbing at an alarming rate, most people can look around and see, yeah, kinda looks like it.
Now global warming may be a very subtle process, but the predictions around it are not subtle, and the computer models runs could be seen by now to be working or not working. You know we've had like 35 years or so to see.
And this is before we even touch on the potential vested interests all round, because any energy alternative is going to be big business for someone, be that wind or nuclear, and besides, on top of that is the separate ethical question of, how can humans become more compassionate on this planet? But before you can do the right thing, you need to know what the right thing is, which comes down to whether the science field got it right.