Comparison between the observed abundance of CH₃ OH (black dots) in Barnard 1b (left) and IC 348 (right) with chemical models. There are three panels on each side, with one target per side. In the top panels, the comparison between the observed gas-phase abundance of CH₃ OH and chemical models is made. Each solid segment, delimited by vertical dashed lines, represents the predicted abundance of a model that fits the observed methanol abundance; the color indicates the set of binding energies of that model. The initial sulfur abundance of that model is displayed in the middle panels with the black solid curve S_CH3OH. The filled area S_H2S from Figs. 12 and 13 is also shown for comparison. Finally, the scaling applied to the binding energy of CH₃OH in each segment is depicted in the bottom panel of each column.