Abstract: For use in a sorption analysis system, a method compensating for measuring error due to the time-dependent evaporation of liquid coolant and the resulting change in the level of the coolant and temperature increase around the stem of the sample cell, during a gas sorption analysis of a sample in the sample cell. This error compensation does not inhibit coolant evaporation and is without recourse to mechanical means or other physical contrivances for causing the system to act as if the coolant were not evaporating. This method employs fixed and time-dependent data, including: changing coolant level and sample cell stem temperature changes, both of which can be obtained off-line, cold zone volume changes, and volumes of adsorptive gas transferred into the sample cell, to generate progressive error correction; whereby, system output is being corrected throughout the duration of the sorption analysis.