Unintended consequences (Score 1)

One very simple negative feedback system for CO2 is the biomass of plants and photosysnthesis. CO2 + sunlight dramatically increases the biomass of plants. Plants LOVE it. If you maintain a planted aquarium and want to achieve explosive plant growth, the decades old, proven approach is to inject CO2 and provide high wattage lighting. Left to it's won devices, the increase in CO2 in the earth's atmosphere will result in similar increases in the vegitative biomass. This will, in turn, CONSUME more CO2. One unintended consequence of a sunshade is to REDUCE the efficiency of phototsynthesis and thereby increase the residual CO2 in the atmosphere. I'm sure there are others that people will think of. Nobody can convince me that global warming is anthropomorphic and that computer models are remotely close to accurate. We can model weather a few days in advance. We can't model systems that are orders of magnitude simpler than the earth's climate (like a man-made, mortgaged-back security market!). Plus, my tan will suffer.