I'd certainly be very wary about even more geo-engineering (which is what AGW basically is) - we would need to be absolutely 100% certain of the outcome - which in science is never the case when looking to the future. If we were 97% certain that nothing would go wrong, would we justify gambling the whole planet on that??
Cheers - John
The Little Ice Age onset started in 25 yrs from 1275 to 1300 A.D.
Read Miller et al. 2012 Abrupt onset of the Little Ice Age triggered by volcanism
and sustained by sea-ice/ocean feedbacks. GEOPHYSICAL RESEARCH LETTERS, VOL. 39, L02708, doi:10.1029/2011GL050168, 2012