Abundance maps of H₂O (left column) and CO₂ (middle column) for the models with no cavity (top row), a 1 AU cavity (middle row) and a 5 AU cavity (bottom row). The H₂O and CO₂ snowlines (defined as n_gas/n_ice = 1) are indicated with solid light blue and pink lines, respectively. The dashed, dark blue line shows the dust τ = 1 surface at 15 µm. The right column shows the gas temperature, with dashed black lines indicating 100 and 300 K. The yellow contours indicate the region in which 90% of the H₂O 11_3,9 − 10_0,1o line emission at 17.22 µm (E_up = 2438 K) originates. The red contours indicate the origin of 90% of the CO₂ v₂ = 1 − 0 Q(20) line emission (E_up = 1196 K).