Climate change is a survival issue due to the risk that positive feedback processes will magnify the initial global warming due to anthropogenic greenhouse gases. Historical records show that climate changes not smoothly but in sudden jumps, due to the balance of positive and negative feedbacks. These can be both physical and biogeochemical processes, and the latter are still not included in most "Global Circulation Models" on which the IPCC projections depend. Therefore we should beware of surprises and possible catastrophes if we continue to emit so much CO2.
The large JPEG Graphic below illustrates briefly the best known climate feedback processes. If you cannot view this graphic, you can also find a list of these feedback processes towards the end of GCI's protocol proposals: 2.14 Strengthen research into Climate feedback processes