Flow records of meltwater runoff provide information about the movement of water through the ice and about glacial ablation. This study indicates that the lag time required for a maximum correlation between daily discharge and air temperature, and the sensitivity of meltwater response to air temperature, changes during the ablation period for different proportions of the base flow. To examine how glaciers respond to climatic changes and the hydrological characteristics of the large glaciers in the Tuomuer mountain area, western China, observations have been undertaken in this region since June 2003. By means of correlation and cross-spectral analysis, the relationship between air temperature and meltwater runoff in different months of the ablation period (May–September) on Keqikaer glacier in 2004 has been evaluated. Data have been selected from the 1st to the 30th for every month, and the calculated hourly discharges of the meltwater runoff for each day were utilized. From these data we conclude that for Keqikaer glacier the meltwater runoff has a greater sensitivity to air temperature in May, July and August than in June and September; however, the lag time is shorter in June, July and August than it is in May and September.