The Information you need to act is part of the 2014 IPCC Report. You can access this document using the following link:
http://ipcc.ch/pdf/supporting-material/EM_GeoE_Meeting_Report_final.pdf
Sub-Subsections of Interest:
Keynote F-2: Geoengineering: A few basic ideas to start our discussion (Page 19)
Keynote I-1: Science and Technology of Solar Radiation Management (Page 20)
Keynote I-2: Residual Climate Change and Unintended Consequences of Solar Radiation Management (Page 22)
Keynote I-3: A Primer on the Economics of Solar Radiation Management (Page 24)
You need more time to slow the buildup of CO2 and eventually remove it completely from the atmosphere. SRM will buy you the time you need at a fraction of the cost of adjusting to the disaster.