METEOROLOGICAL AND RUNOFF TIME-SERIES CHARACTERISTICS IN A SMALL, HIGH-ARCTIC GLACIATED BASIN, SVALBARD

This paper examines characteristics of meteorological and runoff time- series collected from the Broggerbreen glacier basin, Svalbard, during 1991 and 1992. Proglacial discharge and electrical conductivity were monitored at two gauging stations: one immediately downstream of the t erminus of Austre Broggerbreen and another c. 2.5 km downstream, in or der to assess the contribution of the intervening proglacial sandur. M eteorological time-series (incident radiation, wind speed and directio n, air temperature and precipitation) were monitored on the proglacial sandur. Changes in wind direction, incident radiation receipt and air temperature were used as a basis for separating the time-series into different periods. These periods allowed the relative significance of advective and incident (short-wave) radiative forcing of air temperatu res to be determined at diurnal and synoptic time-scales. The analysis shows that incident radiation dominated over advection in the forcing of diurnal variations in air temperature during all the periods. At t he synoptic scale, both processes were periodically dominant in forcin g air temperature variability. An examination of synoptic charts suppo rts the use of ground level measurements to describe the effect of ene rgy advection upon the synoptic air temperature variability and indica tes the role of large-scale circulation patterns in the delivery of en ergy for ablation under different conditions. Interrelationships betwe en the hydrological and meteorological time-series are then used to ch aracterize the response of the glacierized part of the catchment to me teorological forcing throughout the two ablation seasons. The analyses show that the recession of the snowpack across the proglacial and gla cial portions of the basin has an important effect on the catchment co ntributing area contributing to runoff and the lag between energy inpu ts and meltwater discharge outputs. (C) 1998 John Wiley & Sons, Ltd.