Effective Radiative Forcing from GISS-E2-R (NINT) (w.r.t. 1850) 
Calculation uses SST from 1850 and yr 2000 forcings or 2x/4xCO2
ERF (Fs) (W/m2)
Decade All GHG LU Ozone Orb Solar TropAerD TropAerD+I Volcanic BCSnAlB 2xCO2 4xCO2 
1   2.92 3.39 -0.16 0.40  0.06 0.26 -0.42 -1.28 0.37 0.08 4.31 8.23
2   2.73 3.43 -0.14 0.32 -0.04 0.30 -0.33 -1.38 0.29 0.04 4.41 8.17
3   2.83 3.31 -0.10 0.38 -0.05 0.30 -0.32 -1.24 0.34 0.03 4.33 8.23
Avg 2.83 3.38 -0.12 0.37  0.01 0.29 -0.36 -1.30 0.33 0.06 4.35 8.21

Variation across decades is a function of the impact of the unforced 'weather' component. The best estimate comes from an average over three decades (differences in last digits due to rounding). ERF is calculated from the TOA imbalance plus a correction based on the delta(Ts) multiplied by a nominal sensitivity (0.56 degC/(W/m2)).