Strong constraints on aerosol-cloud interactions from volcanic eruptions by Mallavelle, FF, Haywood, JM, Jones, A, Gettelman, A, Clarisse, L, Bauduin, S, Allan, RP, Karset, IHH, Kristjánsson, J, Oreopoulos, L, Cho, N, Lee, D, Bellouin, N, Boucher, O, Grosvenor, DP, Carslaw, KS, Dhomse, S, Mann, GW, Schmidt, A, Coe, H, Hartley, ME, Dalvi, M, Hill, AA, Johnson, BT, Johnson, CE, Knight, JR, O'Connor, FM, Partridge, DG, Stier, P, Myhre, G, Platnick, S, Stephens, GL, Takahashi, H, Thordarson, T