Using infrared spectroscopy, transitions among ice, solution, and clathrate phases are compared with the predictions of the SO2-H2O phase diagram in the temperature range -20 to 10degreesC and SO2 pressures from 50 to 900 mbar. The infrared signatures of clathrate and ice, as well as SO2 in a variety of phases are recorded and interpreted in terms of their environments. The consequences Of SO2 in confined geometries within ice are explored.