Fig. 13

a–f Maps of observations (colored circles) and model ensemble means of atmospheric 137Cs concentration from 3/20/9 h to 3/21/9 h. Areas identified as plumes with concentration larger than 10 Bq m−3 are encircled and labeled with the name of the plume. JMA-MANAL wind vectors at 1000 hPa are superimposed. Movement of the P7 plume route is indicated by a thick arrow in panel a. See the main text for explanation of labels (a, b)