Multiple peer-reviewed publications have shown that small changes in solar activity can have greatly amplified effects upon climate via a variety of mechanisms, including:
1. Galactic cosmic rays/clouds
2. Ocean oscillations, which have been shown in multiple studies to be driven by solar activityhttp://hockeyschtick.blogspot.com/search?q=solar+ocean+oscillations
3. Global brightening following the ice age scare of the 1970′s, due to decreased aerosols/clouds noted in multiple studies around the globehttp://hockeyschtick.blogspot.com/search?q=solar
4. Effects on ozone production from large changes in solar UV within and between solar cycles, which has large secondary effects on surface temperaturehttp://hockeyschtick.blogspot.com/search?q=ozone&max-results=20&by-date=false
5. Forcing due to changes in length of day