"I haven't. So they tell us the temperature is rising, but we don't know what temperature. What a joke..."
Just because you haven't read it, doesn't mean they don't tell us. I may well have read it at some time, but I don't read such things frequently, so I forgot. I don't actually think you can write a scientific paper without giving a definition of the temperature you are talking about.
"We only need to sample every few hundreds of meters or so."
Why? What makes you think so? And what about your house that should be burning up by now? Is it not burning because the house 100m apart is not burning?
Also, maybe with satellites you can measure a lot of spots in one go - maybe even at 100m distance if that is the only thing that would make you happy.
Have you checked that they don't measure 100m apart? Because I get the impression that you just assume they only do bad science, without having checked that assumption.
"you will not be able to predict the (near) future state reliably."
Again, why not? Doesn't it entirely depend on the system and the circumstances? Like if you boil some water on the oven, and you want to know how fast it heats up, I am pretty sure measuring at one point is sufficient to predict the temperature rise for the whole pot of water (because you know it is a pot of water that is being heated from below with constant energy supply). Obviously climate is more complicated than a pot of water, but you still would have to supply better arguments for why you think current methods are insufficient.
What if you care about the ice in the arctic melting away - do you think it is impossible to measure that? (I don't know if it is possible, but for example it seems plausible that the area covered with ice is measurable from space to a high precision).
"If you don't understand the process used to obtain the numbers, you don't understand how much the numbers can be trusted."
Again, give examples of cases were you think the scientists did not do what was due. Naturally I can not verify their results directly (at least not without a significant investment of time). However, I can have a certain degree of confidence in the system that made them scientists, peer reviews and so on. (Edit: for example if they turn out to be merely popular fiction authors or philosophers, I am less inclined to believe them than if they are actually climate researchers)
Again, what makes you think they are all wrong - can you point out specific examples in major papers that are cited a lot in the debate?