Geo-Engineering should definitely be researched. At some point, the current surplus of CO2 will turn into a shortage. Plants and weathering of rocks ensure that will happen. Meanwhile, global warming is a real and present danger.
Cap and Trade has proven itself to be worse than useless. Due to inevitable corruption in the markets for carbon credits, the whole system will lead (and in several cases is leading) to more CO2 emissions, not less. Tax and Rebate is a much more reliable (if politically less acceptable) method of incentivizing CO2 reductions. Even better would be to make it cheaper to use greener technologies. There are promising research avenues being pursued now which makes that seem likely to develop in the near future. For example… who wouldn’t want to drive an electric car with an effective fuel cost of pennies per gallon of gas equivalent energy and with better performance?
Meanwhile, maybe the Icelandic volcano eruptions are just the beginning of extra volcanism (as glaciers melt and remove pressure on some tectonic plate boundaries) which will ground air traffic and inject massive amounts of ash into the stratosphere, thereby offsetting global warming for a while? The problem of acidification of the oceans will still need to be dealt with, so we still need to use that possible respite from excess atmospheric heating to resolve the excess CO2 problem. Maybe storing it underground so we can get at it if it is needed in the future would be a good idea… and/or maybe genetic engineering to give more plants that more efficient photosynthesis system that corn has and developing plants that store the carbon in long lasting wood would do the trick.
Ultimately, we need to develop rapidly deployable global thermostat controls which will allow us to compensate for variations in solar radiation levels and in the inclination of the earth’s axis of rotation to its orbital plane. That mini-ice age of the 12th century was no fun and the next one probably won’t be either.
The earth has had “snowball earth” phases in the past. We want to be able to deal with a positive feedback loop in that direction as well as the current excess warming feedback loop.