Opportunistic experiments to constrain aerosol effective radiative forcing by Christensen, MW, Gettelman, A, Cermak, J, Dagan, G, Diamond, M, Douglas, A, Feingold, G, Glassmeier, F, Goren, T, Grosvenor, DP, Gryspeerdt, E, Kahn, R, Li, Z, Ma, P-L, Malavelle, F, McCoy, IL, McCoy, DT, McFarquhar, G, Mülmenstädt, J, Pal, S, Possner, A, Povey, A, Quaas, J, Rosenfeld, D, Schmidt, A, Schrödner, R, Sorooshian, A, Stier, P, Toll, V, Watson-Parris, D, Wood, R, Yang, M, Yuan, T