High-Resolution Measurements of Water Discharge, Sediment, and Solute Transport in the River Zackenbergelven, Northeast Greenland

Abstract

The climatic control on fluvial fluxes of sediments and solutes from terrestrial ecosystems to the hydrographically sensitive and highly productive 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 solute chemistry in the river Zackenbergelven draining a catchment of 512 km2 in High Arctic Northeast Greenland. Variations of water quality and water discharge in the river are discussed in relation to climate, water balance, and drainage basin dynamics. The temporal variations in water composition 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 ion pulse. Later in the season, when the active layer in the permafrost develops, the water quality is mainly influenced by water draining through and from the active layer. In the latest part of the season, when air temperature reaches the annual maximum, and drainage from the lowland areas ceases, the 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 from the catchment seems to be especially sensitive to even slightly changing climates during the mid period. It is concluded that the river is intermediate between the arctic nival regime and the proglacial regime, and it is suggested that the Zackenbergelven drainage basin is representative for Northeast Greenland drainage basins with no connection to the Greenland Ice Sheet in the more continental part of the land fringe outside the ice sheet.