You are just looking at statistics and ignoring the physical. 1. CO2 is a greenhouse gas. This is a fact. It has been known for over a hundred and fifty years. Denying it, is like denying gravity. 2. The amount of CO2 in the atmosphere is rapidly rising. Also a fact. 3. That humans are responsible for rise of CO2 is shown by isotopic studies of CO2 in the atmosphere. 4. The influence of CO2 in the atmosphere has been measured by satellite spectrographic studies, confirming that it is indeed acting as a greenhouse gas. 5. Observed warming of the surface and lower atmosphere has been accompanied by observed cooling of the stratosphere. There is no other satisfactory physical explanation for this other than the greenhouse effect. The same behavior is observed on Venus (in a much more extreme form) which has the mother of all greenhouse effects. There is very little doubt about all this. The question is not "if", but how much. The range is believed with high confidence to be 2C - 4.5C per doubling of CO2. The reason why CO2 gets so much attention is that it is contributing most to the change. Other GHGs are also important. Increased CO2 persists in the atmosphere for a long time - hundreds of years - even if humans stopped large CO2 emissions immediately. Other GHGs are mostly scrubbed from the atmosphere more quickly.
You left out the FACT that CO2 changes LAG temp changes. When you include that FACT the picture isn't so clear now is it?
Yes, it's guessing. Some guess better than others, but unless you can tell me with exact certainty where the market will be at tomorrows close, you're guessing. You're also guessing what the climate will be like some years out, and you're really guessing about what will cause the end of the world as we know it that climate cultists love to pontificate about. Absolute certainty does not exist regarding events that have yet to happen.
That is only a statistical observation of some past climate changes. When humans were not emitting large amounts of CO2 into the atmosphere, and other factors initiated change in climate. It is not a fact relating to physical mechanism and there is no reason at all that it should always be the case. It is not a law of nature. You are just "playing with numbers" - not looking at physical reality.
Nobody is trying to predict tens of thousands of years into the future. Therefore your comment is irrelevant.
It is not only a statistical observation. It is not playing with numbers. They went back 420,000 years into the climate record using ice cores and it absolutely showed that CO2 lagged temp. It has nothing to do with where the CO2 came from. We have another strange claim from GW hoaxsters that heat somehow differentiates between "natural" CO2 and "man-made" CO2. It is absolutely bizarre.
No, you don't understand what the word means. A guess is an estimate based on little or no information. A forecast is "the process of analyzing current and historical data to determine future trends." Absolutely agree. There's no way to know for 100% certainty that the sun will rise tomorrow. However, the preponderance of the evidence says it will.
If you're able to ignore the very nature of the CO2 molecule, in favor of ten thousand year old ice cores (that don't show what you think they do) then yes, you are guilty of playing with numbers. You're just picking whatever interests you rather than weighing the evidence. CO2 is CO2. Unless we're talking isotopes, then there are differences. Do you understand what an isotope is?