Hydrological characteristics of the drainage system beneath a surging glacier

Subglacial drainage systems are inaccessible and their surges are infrequent, and normal field observations only provide limited support for certain models. The major discharge of water from an ice-dammed lake which drains along the glacier bed, can offer the chance to test current hypotheses, as outburst floods during glacial surges can be compared with those occurring during normal periods.