One of the themes that has run through prior posts is to note that our understanding of the carbon cycle may leave more than a little to be desired. Such lack of understanding may explain why the impacts of global warming are, in some cases, more severe than anticipated, and in some cases less severe. The climate trend is unfortunately not favorable, but the rate and impact of the trend still appears somewhat fuzzy even as earlier impacts are being made manifest (e.g., changes in migration patterns of various animals, spread of various diseases impacting forests).
A good example is what may be a new discovery in the oceanic carbon sink that may assist with decreasing the rate of climate change. "Understanding how the oceans absorb carbon dioxide is crucial to understanding the role of that gas in the climate. It is rather worrying, then, that something profound may be missing from that understanding. But if Jiao Nianzhi of Xiamen University in China is right, it is. For he suggests there is a lot of carbon floating in the oceans that has not previously been noticed. It is in the form of what is known as refractory dissolved organic matter and it has been put there by a hitherto little-regarded group of creatures called aerobic anoxygenic photoheterotrophic bacteria (AAPB). If Dr Jiao is right, a whole new 'sink' for carbon dioxide from the atmosphere has been discovered."
For the balance of this fascinating article, see http://www.economist.com/node/16990766?story_id=16990766. Dr. Jiao's article (in English) on this topic can be found at http://lib.bioinfo.pl/auid:5160424. In Chinese, the article can be found at http://www.sciencemag.org/content/328/5985/1476/suppl/DC1.