Correlation between the phase-variation of the temperature profile and the clustered light curves from M25. Top: example temperaturevariation curves drawn from three representative pressure levels in the atmosphere (highlighted boxes) compared to correlated or anticorrelated light curve clusters. Bottom: correlation coefficient between the temperature-variation at that pressure and the clustered light curves for each pressure level, as well as the correlation to the effective temperature in the right-most column. The pressure levels for the temperature curves in the top panels are highlighted with coloured boxes. Horizontal lines and annotations indicate the location of atmospheric features.