It so happens that nearly all climate science detractors ARE unscientific.
And that is the sort of reason why nearly all climate science detractors are unscientific. Or perhaps it's because they are unscientific they are climate detractors. Frankly, I'm not interested in arguing the toss.
It is one thing to have sufficient understanding of the past to be able to explain it satisfactorily in scientific terms, but quite another to be able to predict what a complex, interactive system, with many positive and negative feedback loops, will do in the future.
The most common way of understanding how complex systems work is to hold all the other variables constant while you test the effect of varying just one.
So let's suppose that you have a suspicion based on general theory that some quantity such as the amount of CO2 in air might have some effective in changing how that air passed through or absorbs radiation at particular frequencies, and therefore the temperature to which it should rise when subjected to said radiation. So, in a lab, you conduct experiments and derive a numerical relationships between CO2 levels and the absorbance of radiation across the solar spectrum. Now you think you know what's going on - you have theoretical understanding, and numerical data which allows you accurately to predict what will happen in the lab.
Now you go outside, and measure the CO2 in the atmosphere and the temperature. To be kind to you as our hypothetical experimenter in this hypothetical discussion, we'll initially make it easier by assuming no seasonal or short term variability, yet even so, you find the two quantities no longer correlate as they did in the lab. You then think that perhaps the water vapour might also be affecting radiation absorbance, so you go away and repeat all your experiments with water vapour, but when you come outside again, things still don't work out the way you'd hoped, because, it turns out, the temperature affects the amount of water vapour in the air, your first discovery of a feedback loop, and methane is also a greenhouse gas.
And so it goes on. Assume for the sake of argument that you've been doing good science, yet at no stage are the results outside ever completely accurate. But that doesn't make your science bullshit, on the contrary, your understanding is increasing all the time. You have never been 'wrong', in the sense that the numerical relationships that you derived are all perfectly valid, but the sheer complexity of the system that you're trying to understand prevents your predictions ever being entirely 'right'. In a live system such as the Earth there are a great many interrelating factors, and even when you've sorted all the most important ones that cause the long term trends you're trying to pin down, there are still a great many interactions and variables causing short term variability that in numerical terms completely mask those long term trends.
This why it is important not to judge the models on their failure to predict short-term variability. If they are any good at all, they are much more likely to be right over the long term, probably about 40 years or more.