Wow! We got bigger problems than I realized. That some species evolve is scientific fact. Pretty much anything else you could say about evolution would be theory. The Big Bang is likewise a theory and nowhere near "fact". Are you aware what the qualifications are for establishing scientific fact? Any fact, for that matter?
For the very reason that your progression is too simple. There is much more involved than you want to acknowledge. But I'll answer your question: I disagree with all the numbers. That is not to say that I believe they are all wrong. I disagree with your attempt to etch them in stone as if they are verified truisms. They are not. Why? My answer to this was given in my inital reply, and I'll give it again.
Yes, you do need to know it if you want to make a thorough exploration of the topic; if you want to cross check your data; if you want to verify your observations; in short, if you want to make a scientific inquiry into the topic and not just a cursory, back-of-the-envelope calculation that will give you the numbers you need to support a preconceived conclusion. For example, if the total amount of carbon sequestered on the planet in 1750 was X, and the total amount of carbon sequesterd on the planet today is X+N, then being an open system means something in terms of carbon. If you don't know this information, then you might jump to the conclusion that any increase in carbon, in whatever form, is due to some other factor. You would be making a post hoc, ergo propter hoc argument - which is false.
The answer is not known, the answer is estimated. You got these numbers from ice core data, a certainly valid proxy for CO2 concentrations. But they are still just estimates based upon what we currently know about using ice cores as proxies for historical atmospheric composition. Recent studies with stomatal proxies have shown that CO2 concentrations may not have been as stable as the ice core data lead us to believe. In fact, the error band could be as great as +/-100ppm. But, these are also only estimates.

Even if we simply accept your numbers, that's an error rate of 7%. So, it is possible that CO2 concentrations were 10ppm higher in 1750 than your equation accounts for, and 10ppm lower today than your equation accounts for. That means your estimate of 1100gT for how much CO2 has been emitted by Man is within +/-77gT (1100*.07). Meaning, your estimate for how much CO2 has been emitted by Man could be 1023gT.
There is an error band available. There's an error band for every measurement ever created. Why haven't you looked for it? If you're going to infer this number from ice core data and MLO measurements then the math is done above for you. But if this number was just given to you, without any mention of what the error rate is, then whoever gave it to you is being dishonest with you. The web-site you got the number from even admits that this number is just an estimate. Your very wording ("About" 1100gt) implies there is an error rate.

So, why isn't that important to you? If you're looking for the truth, wouldn't you be concerned about how statistically relevant the numbers you're repeating are?
How much carbon has been emitted naturally since 1750 is unknown, very good. But there are estimates. And we should know what those estimates are. What we'll find, I'm sure, is that the amount of carbon emitted naturally is a very big number. And even if our estimates are very, very good, with a small rate of error, that small rate of error is going to equate to a very large discrepancy in gTs. And that large discrepancy is going to greatly impact whether we're net contributors to atmospheric CO2, and to what extent. Again, for someone who professes a desire to learn the truth, I would think you would seek these validations out.
Again, bingo! Again, there are estimates. Again, those estimates will have a range of error. Again, knowing those estimates and knowing those error rates mean something to our equation.
Yes, a very certain conclusion that you're looking for. I can also find numbers to validate any conclusion I choose.
Gosh, it's all so simple! Why didn't I think of that? I put 100 marbles in a box (give or take 7). There were 100 marbles in the box before (give or take 7). Now, there are 190 marbles in the box. There should be 200 marbles in the box! The box must be eating the marbles!
No, we don't know that it's gone from the atmosphere. Our estimates indicate that it should be gone from the atmosphere, but it's not showing up anywhere else. So, something must be off. Perhaps we're not measuring the amount of carbon in the air correctly? If we're not measuring the current amount of carbon in the air correctly, or if we didn't measure the past amount of carbon in the air, or both, then our equations will be wrong. If we're not measuring the current amount of carbon in the oceans and biosphere correctly, or if we're not measuring the amount of past carbon in the oceans and biosphere correctly, or both, then our equations will be wrong. Even if we're measuring the amount of carbon Man is putting into the air correctly, then one, two, three, or all of the other estimates must be wrong.
No, it wouldn't. It would only require that our estimates in toto are off by 50%. Any permutation of the numbers, how they're derived, how they're interpreted, how they're applied, etc. could be wrong.
So, we know everything about how the atmosphere (massive when compared to the biosphere) absorbs carbon, but we don't know where carbon goes anywhere else? But we can make definitive conclusions about one part of the carbon cycle and that allows us to make definitive conclusions about the entire carbon cycle? Got it.
Yes, we do if we want to be assured that our estimates are reasonable. A good example of this is the claim you made that a 10C increase in temperature leads to a 100ppm increase in CO2. When you tried to back up that number with empirical evidence, you came up with the answer that a 10C increase in CO2 leads to a 200ppm increase in CO2. An error rate of 100%. At least one of your claims needs to be wrong. An intelligent and curious person would wonder why and try to find out the answer.
How much nature has contributed can be inferred from the two estimates, either of which could be grossly over, or under, exaggerated. Therefore, making conclusive statements like the ones I quoted are not logical.
What? What does that have to do with anything? Are you implying we can simply regress the current estimate back 250 years at 2ppm? Gee, I really hope not.

By the way, what's the error rate on that 2ppm?
It would not require massive errors in those numbers. Since we're dealing with a multitude of estimates, with a multitude of error rates, it only takes a cummulative error rate that would take us from 13gTs/yr (the extra you claim we're adding to the atmosphere) to 0. That's 13gTs on how much tonnage is exchanged every year? Can we even get to a reasonable number for the tonnage when we don't even know all the sources and sinks of carbon?
What a silly little ploy for someone so intelligent, onon. It isn't a hoax when well meaning scientists simply draw incorrect conclusions from incomplete data. They're just doing the best job they can. And they tell us what they don't know. If you're talking about politicians, then that's a different matter. But I don't get my scientific information from politicians. Do you?
Yea, I noted it. What of it? Are you saying your statements aren't specific? They sounded pretty specific to me.

As to temperature changes, here's what we know and the last I'll say about it. I have no interest in entering this debate again:
Temperatures before the late 1970s are poor guesses at best. These temperatures were taken by infant thermometers located in rural areas, on land, in the Northern hemisphere. As such, these readings are hardly specific and could hardly be interpolated as indicative of the entire planet's temperature. We were taking the temperature of less than 1/6 of 1/2 of the planet with tools having an error rate greater than the claimed temperature rise. Not to mention the fact that we were taking the temperature of only a fraction of the entire atmosphere.

When we started using better tools in the late 1970s (particularly satellites) we started getting an idea of what the global temperature is. Over that time period, it is clear the globe has warmed.

One fact on this subject which is very germane to our debate is the results of weather balloon temperature readings. Initially, these readings indicated no warming. In fact, they indicated a slight cooling. As they learned more about the subject, researchers continued to refine the data. It was only last year when they changed their conclusions 180 degrees - the data was showing a statistically measurable warming.

Now, were these scientists simply trying to pull off a hoax? Did their initial estimates prove, beyond all doubt, that the globe was cooling? Were they making definitive statements? Were they claiming their data was "known"? Of course, the answer to all these questions is, "No." They were just doing the best job they could with the data they had. And all the while they sought to improve upon their knowledge without claiming "the debate was over".