Laboratory experiments explored the sorption behavior of SO2 on ice between the temperatures of -30 and -5 ¿C and with SO2 mixing ratios of 15 to 95 ppb. The time-dependent data show clear evidence of two distinct exponential time constants and a dependence on SO2 concentration. The equilibrium amount of SO2 retained by the ice, determined by integration of the kinetic data, was found to increase strongly with temperature. The experimental results may be interpreted in terms of a disordered surface region which increases in thickness with temperature, enlarging the storage reservoir and generating the observed temperature dependence. ¿ American Geophysical Union 1989