You don’t know all the other factors. Nobody knows all the factors. To pretend that we have absolute certainty about all the factors that go into atmospheric CO2 levels, much less global average temperature, much less the economic impact of global average temperature is absolutely ludicrous.
Let me be clear again about the onus on you:
1) a list of observations, which if observed, mean a hypothesis is false;
2) a logical argument that the lack of those falsifications means that a hypothesis must be favored over all others (including the null).
You have provided neither item required for a necessary and sufficient falsifiable hypothesis statement. Please, at least *try* to follow the rules of the scientific method if you want to be taken seriously in a scientific discussion.