Precipitation measuremeiits have a weii-documeiited and mostly wind-dependent bias whicii is especiaiiy apparent during solid precipitation events. The resulting inaccuracy in precipitation data remains an area of concern in quantifying regional and global climate trends. As a high-latitude country, Norway has many solid precipitation events often accompanied by high wind speeds where the current adjustment functions have only limited validity. The presented study aims at improving the quality of solid precipitation data. In a comprehensive field experiment, precipitation data of standard automatic gauges are compared with data of a reference gauge surrounded by a double fence construction to minimize wind impact. Additional meteorological parameters are measured at the test site, allowing for an in-depth analysis of high-temporal-resolution precipitation data. The goal is to develop new adjustment functions for solid precipitation measurements which account for Norway's typical climate and are suitable for automated measurements. Measurements began in winter 2010/2011 at the alpine test site in southern Norway (chosen after a pre-study in 2009/2010) and will continue for two more winters. In this paper, the test site and its instrumentation are described and preliminary results are presented.

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This paper presents a statistical correlation procedure to predict a master depletion curve by use of basin characteristics and the specific storage of water available for runoff at a particular recession discharge in small watersheds. Percentual lake area, drainage density and a weighted lake inflow area index are the most significant parameters to explain differences in specific storage among basins. The significance shows time-dependency. Percentual lake area has a decreasing contribution to a total explanation from high to low specific discharges, while drainage density increases its importance.

A procedure to isolate and investigate the watershed influence on storm runoff is presented. It offers an opportunity to study also the change in influence of particular watershed characteristics by changing the input or soil moisture state of each catchment. Weighted lake area, area of bare rocks, main stream gradient, drainage density and basin area are found to be the most significant characteristics in affecting peak runoff and time of rise on storm hydrographs in small Norwegian rivers. The intercorrelation structure of the watershed properties is examined.