Major research issues/sites:

Monitoring of freshwater and climate research

Short technical description:

The Lake Langtjern buoy measures water temperature using a thermocouple at 8 different depths (0.5m, 1m, 1.5 m, 2m, 3m, 4m, 6m, 8m). Oxygen saturation is measured with a Aanderaa Optode 4175 at depths of 1m and 8m. At the lake outlet temperature is measured in air, water and soil (10 cm) using a thermocouple. pH is measured with a Honeywell Durafet II and conductivity with a Honeywell graphite electrode, both having a direct line transmitter (4-20 mA). Water level is measured with a pressure cell. Coloured dissolved organic matter (CDOM) is measured with a TriOS Microflu-CDOM (ex 370nm/em 460nm) (D, small sensor) and UV-absorption with a TriOS ProPS (190-360 nm) (D, large sensor) with a 1 cm light path.

Both have mechanical wipers to remove biofilm. Additionally water flow is measured at the inlet LAE03. A new weather station was installed at Langtjern in November 2012, replacing a station from 2011. Air temperature and relative humidity is measured using a Campbell Scientific CD215. Global radiation with a Apogee SP-212 sensor. A Young Model 05103-5 measures wind speed and direction. In addition a web camera is installed at the station (Campbell Scientific CC5MPX). A sensor monitoring precipitation (Geonor T-200B) will be installed at the station in the near future. For power generation in this remote area solar panels and a methanol fuel cell have been installed. A small cabin is set up by the outlet to house various instruments.

Specific features/uniqueness:

The catchment has not been disturbed by any direct human interference since early in the 20th century.

Options and conditions for visiting scientists:

Please enquire for more information.

Unit Cost of use and principles of costing:

On demand