High-resolution measurements of water discharge, sediment and solute transport in the river Zackenbergelven, Northeast Greenland

The climatic control on fluvial fluxes of sediments and solutes from arctic terrestrial ecosystems to the hydrographically sensitive and highly produc tive marine ecosystem are considered to be an important feedback mechanism in relation to the understanding of global change. High temporal resolution data are presented on water discharge, suspended sediment transport, and s olute chemistry in the river Zackenbergelven draining a catchment of 512 km (2) in High Arctic Northeast Greenland. Variations of water quality and wat er discharge in the river are discussed in relation to climate, water balan ce, and drainage basin dynamics. The temporal variations in water compositi on in the river can be separated into three characteristic periods. During the early part of the season, snow melt in the lowland areas produces an io n pulse. Later in the season, when the active layer in the permafrost devel ops, the water quality is mainly influenced by water draining through and f rom the active layer. in the latest part of the season, when air temperatur e reaches the annual maximum, and drainage from the lowland areas ceases, t he river water mainly originates from glaciers and snow patches on the high -lying plateaus above 1000 m a.s.l. The fluxes of sediments and solutes fro m the catchment seems to be especially sensitive to even slightly changing climates during the mid period. It is concluded that the river regime is in termediate between the "arctic nival regime" and the "proglacial regime," a nd it is suggested that the Zackenbergelven drainage basin is representativ e for Northeast Greenland drainage basins with no connection to the Greenla nd Ice Sheet in the more continental part of the land fringe outside the ic e sheet.