The Global Carbon Cycle by David Archer, is one of the excellent series of Princeton Primers in Climate. These are short, economically priced (in the paperback or Kindle editions), slightly technical discussions of aspects of climate.
The carbon cycle is the movement of Earth's stock of carbon among its several reservoirs - the solid earth, the oceans, fossil fuels, the soils, the biosphere, and the atmosphere. The atmosphere is the smallest of these but it is also the one crucial for anthropogenic climate change and climate change more generally. The movements are complex, imperfectly understood, and, again, crucial for our understanding of the effect of carbon on the climate.
Archer's book explains much of what is known, something about how it is known, and discusses those things that aren't known, all in concise fashion. I liked the book and learned a lot, but I still have a number of complaints. The Kindle version is cheap ($19.25) and easy to carry on my phone, but the not very numerous equations are rendered as tiny images which are difficult (or were difficult for me) to magnify. In some cases, the author gives different numbers for the same quantities, like the amount of carbon in natural gas reservoirs, for example. To be sure, estimates vary, but I would prefer that he give a range rather than quote different estimates in different places. I would also prefer a more structured organization scheme, with more chapters and fewer topics in each.
Despite it's generally careful approach to the unknown aspects of the problem, the author occasionally lets his alarm at human caused climate change emphasize, or perhaps overemphasize, the worst case scenarios.
In my many arguments with climate skeptics, I have found that the carbon cycle is one of the things about which they are most deeply confused. Its complexity makes it a convenient dumping ground for all kinds of magical thinking, but they could learn a lot by reading this book. That, however, is something that they are unlikely to do.