EARTHSC 2GG3 Lecture Notes - Acoustic Doppler Current Profiler, Drainage Basin, Broad Valley

• School: McMaster University
• Department: Earth Sciences
• Course: EARTHSC 2GG3
• Professor: Sergei Basik

Document Summary

A river is not a fixed structure: subject to natural processes, changes course, floods. River a complex network of interconnected channels. Many small tributaries flow to few large streams that flow to one major river. Valleys are eroded over thousands of years. Response to changes in: climate, amount and variability of flow, size and amount of sediment particles supplied to channels. Streams collect water and carry it across land to ocean. Streams accumulate surface water from watershed (drainage basin) Drainage basin: upstream area from which surface water will flow toward channel, largest in the world: the amazon river basin (about 7,000,000 square km, largest in canada: the mackenzie river basin (1,805,200 square km) Annual total discharge: amazon: 6923km3/year, ganges: 1386km3/year, congo: 1320km3/year, canada (mackenzie): 325km3/year. Point velocities: measured at equal intervals and depths across the channel. Acoustic doppler current profiler: measures water velocity at hundreds of locations based on shift in sound frequencies due to moving particles.