Fig. 6. Simulated thermal plumes (left column) and corresponding temperature differences (right column) at 10 d using various thermal conductivity distributions. The thermal plumes on the left are shown using (a) a 10% decrease in the observed field, (b) the observed field, and (c) a 10% increase in the observed field. The corresponding temperature differences on the right were obtained by subtracting the plume temperatures simulated in the heterogeneous fields (a, b, and c) from plume temperatures simulated using equivalent mean thermal conductivity fields in the saturated and unsaturated zones of (d) 2.16 and 1.57 W m^–1 K^–1, (e) 2.40 and 1.73 W m^–1 K^–1, (f) and 2.64 and 1.89 W m^–1 K^–1, respectively.