Gasses distribute pretty evenly.
A single data point, even a single source, is not a reliable basis for anything.
The change in CO2 being plotted is several orders of magnitude beyond what volcanic eruptions can produce,
Research demonstrating rise in CO2 levels is funded by several groups around the world, and vetted by peer review; as is research on the rise in global temperatures, the association between CO2 and global temperatures, and the history of climate change.
Scientists claiming "it's not as bad as all that" are funded by the major oil companies; and even they do not question that human activity has sent the atmospheric levels of CO2 skyrocketing.
The research itself isn't saying "there is a problem"; it is saying, "These are the facts, and here's what's associated with them."
"There is a serious problem" is how we understand the facts; "Oh my god, the world is gonna catch fire" is how the press portrays it.
Yes, the earth has been a lot hotter than it is now -- all that carbon that we're pumping out of the earth and burning used to be in the atmosphere. And yes, to say it's out of the earth's "normal range" is a little presumptuous. But as humans, we really shouldn't care about the "normal range" of Earth temperatures in absolute, or the fact that the earth was once boiling hot. We should care about the temperatures necessary to sustain human life.
The bandwagon was twenty years ago. Now it's just cold, hard facts.
Human ingenuity might get us out of this, but there's far more of us now than there ever was; resources (such as water and food) are already scarce -- climate change will make that even worse; and the global economy has a single point of failure: burning carbon for energy.
It's time to get ingenious.