The USH-8 Ultrasonic Snow Depth Sensor by SOMMER is ideal for the reliable measurement of snow-depth in extreme conditions. The sensor’s principle of measurement deals with the transit-time measurement of an ultrasonic pulse. The sensor transmits several energy-charged pulses to the snow cover and subsequently receives its reflected signals. Based upon the required transit time of the ultrasonic signals, the USH-8 sensor calculates the current snow depth. The processing time of the ultrasonic pulses here is enormously influenced by the air temperature. For this reason, the snow depth sensor also possesses integrated temperature compensation. This takes into account the influence of the air temperature on the processing time of the ultrasonic signals, in the calculation of the snow depth. The calculation takes place in the sensor, so that the output signal provides the already converted snow depth. USH-8 Specifications: Snow Depth Measurement Range of measurement: 0 to 8 m Minimum distance to the maximum expected snow depth: 1 m Accuracy: 0,1 % (FS) Resolution 1 mm Principle of measurement: Ultrasonic (Frequency 50 kHz; Angle of reflected beam 12°) Integrated Compensation of the Air Temperature Temperature sensor: Integrated air-temperature sensor in self-venting radiation shield Range of measurement: -35 to 60 °C Resolution: 0,1 °C Non-linearity: ? 0,15 % Interfaces Analogue: Snow depth measurement 0/4 - 20 mA signal (configurable) Resolution: 12 Bit Max. load: 300 ? Digital: Snow depth measurement; air temperature; quality flag RS 232; serial interface Protocol: Various ASCII formats

From 2004 to June 2013 the staion was equipped with the LSI-Lastem DMA570 termohygrometer. Since 2013 the sensor was replaced with the new one: Vaisala HMP155 Humidity and Temperature Probe. Feature/Benefits: ▪ Vaisala HUMICAP®180R sensor superior long-term stability ▪ Optional warmed humidity probe and chemical purge ▪ Plug-and-play ▪ USB connection for service use ▪ Fits with DTR13 and DTR503 radiation shields and also for a Stevenson screen ▪ Weather-proof housing IP66 ▪ Optional, fast temperature probe ▪ Different output possibilities: voltage, RS-485, resistive Pt100 ▪ Applications: meteorology, aviation and road weather, instrumentation Technical characteristics: Relative humidity Measurement range 0 ... 100 %RH Accuracy (incl. non-linearity, hysteresis and repeatability) at +15 ... +25 °C (+59 ... +77 °F) ±1 %RH (0 ... 90 %RH); ±1.7 %RH (90 ... 100 %RH); -20 ... +40 °C (-4 ... 104 °F) ±(1.0 + 0.008 x reading) %RH; -40 ... -20 °C (-40 ... -4 °F) ±(1.2 + 0.012 x reading) %RH; +40 ... +60 °C (+104 ... +140 °F) ±(1.2 + 0.012 x reading) %RH; -60 ... -40 °C (-76 ... -40 °F) ±(1.4 + 0.032 x reading) %RH Factory calibration uncertainty (+20 °C /+68 °F); ±0.6 %RH (0 ... 40 %RH)*; ±1.0 %RH (40 ... 97 %RH)* * Defined as ±2 standard deviation limits. Small variations possible, see also calibration certificate. Recommended humidity sensor HUMICAP®180R(C) Response time at +20 °C in still air with a sintered PTFE filter 63 % 20 s/ 90 % 60 s Temperature Measurement range -80 ... +60 °C (-112 ... +140 °F) Accuracy with voltage output at -80 ... +20 °C ±(0.226 - 0.0028 x temperature) °C; +20 ... +60 °C ±(0.055 + 0.0057 x temperature) °C passive (resistive) output according to IEC 751 1/3 Class B ±(0.1 + 0.00167 x |temperature|)°C RS485 output -80 ... +20 °C ±(0.176 - 0.0028 x temperature) °C +20 ... +60 °C ±(0.07 + 0.0025 x temperature) °C Accuracy over temperature range (opposite) Temperature sensor Pt100 RTD Class F0.1 IEC 60751 Response time with additional temperature probe in 3 m/s air flow 63 % <20 s/ 90 % <35 s

At the AWS Urdukas station the DQA035 Lsi-Lastem rain gauge is mounted on a 1,5 m mast. This model of Rain gauge has a 1.000 cmq collector area. The measurement device is composed of a collector cone and a double chamber bascule connected to a magnete that operates one (optional two) reed switch, which generates impulses that can be counted by external meters: each impulse is equal to 0.2 mm of rain (optional from 0.1 to 0.5 mm). The mechanical and electrical specifications are: - Collector surface area: 1000 cmq - Collector area diameter: 420 mm - Measurements range: 180 mm/hr - Resolution: o,2 mm/imp. (opt. 0,1; 0,3; 0,4; 0,5; mm/imp.) - Accuracy: 0-1 mm/min: 1% 1-3 mm/min: 2% 3-5 mm/min: 4% 5-10 mm/min: 8% - Contact: 1 reed (opt. N.2 reed) 0,5 A/24V non inductive - Pulse duration: 100 msec.± 5 - Collector cone material: Brass - External housing material: Inox AISI30 - Tipping bucket material: Alluminium - Cable: 10 m - Weight: 6,3 kg - Power supply: /thermocover 100 W, 24 Vca/Va

At the AWS Urdukas station the CM6B Kipp&Zonen pyranometer is installed. It is mounted on a 2m pole. The CM6B is a first class pyranometer as defined by the World Meteorological Organization. It is suitable for the measurement of solar irradiance on a plane surface (W/m2). It incorporates a 64-thermocouple sensor, which is rotationally symmetrical, housed under K5 domes. A white screen prevents the body of the pyranometer from heating up. The pyranometer is supplied with a spirit level and screws for accurate levelling. A drying cartridge keeps the interior free from humidity. The technical characteristics are: - Spectral range 305...2800 nm (50%points) - Sensitivity 9...15µV/Wm-2 - Impedance 70...100 Ohm - Response time 1/e 5 s, 99 % 55 s - Non-linearity <1.5 % (<1000 W/m2) - Tilt error <1.5 % at 1000 W/m2 - Operating temperature -40...+90 °C - Temperature dependence of sensitivity +/- 2% (-10...+40°C) - Maximum irradiance 2000 W/m2 - Directional error <+/- 20 W/m2 at 1000 W/m2 - Weight 0.85 kg - Cable length 10

At the AWS Askole station the CM6B Kipp&Zonen pyranometer is installed. It is mounted on a 2m pole. The CM6B is a first class pyranometer as defined by the World Meteorological Organization. It is suitable for the measurement of solar irradiance on a plane surface (W/m2). It incorporates a 64-thermocouple sensor, which is rotationally symmetrical, housed under K5 domes. A white screen prevents the body of the pyranometer from heating up. The pyranometer is supplied with a spirit level and screws for accurate levelling. A drying cartridge keeps the interior free from humidity. The technical characteristics are: - Spectral range 305...2800 nm (50%points) - Sensitivity 9...15µV/Wm-2 - Impedance 70...100 Ohm - Response time 1/e 5 s, 99 % 55 s - Non-linearity <1.5 % (<1000 W/m2) - Tilt error <1.5 % at 1000 W/m2 - Operating temperature -40...+90 °C - Temperature dependence of sensitivity +/- 2% (-10...+40°C) - Maximum irradiance 2000 W/m2 - Directional error <+/- 20 W/m2 at 1000 W/m2 - Weight 0.85 kg - Cable length 10

The CNR1 net radiometer by Kipp & Zonen is for applications requiring research-grade performance. The radiometer measures the energy balance between incoming short-wave and long-wave IR radiation versus surface-reflected short-wave and outgoing long-wave IR radiation. The CNR1 consists of a pyranometer and pyrgeometer pair that faces upward and a complementary pair that faces downward. The pyranometers and pyrgeometers measure short-wave and far infrared radiation, respectively. The CNR1 also includes an RTD to measure the radiometer’s internal temperature and a heater that can be used to prevent condensation. CNR1 Specifications Sensors: Kipp & Zonen’s CM3 ISO-class, thermopile pyranometer, CG3 pyrgeometer, PT100 RTD Spectral Response Pyranometer: 305 to 2800 nm Pyrgeometer: 5000 to 50,000 nm Response Time: 18 seconds Sensitivity Range: 7 to 15 ?V W-1 m2 Output Range Pyranometer: 0 to 25 mV Pyrgeometer: ±5 mV Expected Accuracy for Daily Totals: ±10% Directional Error: <25 W m-2 (pyranometer) Heating Resistor: 24 Ohms, 6 W at 12 Vdc CE Compliance: CE compliant under the European Union’s EMC directive

At the AWS Askole station the DQA035 Lsi-Lastem rain gauge is mounted on a 1,5 m mast. This model of Rain gauge has a 1.000 cmq collector area. The measurement device is composed of a collector cone and a double chamber bascule connected to a magnete that operates one (optional two) reed switch, which generates impulses that can be counted by external meters: each impulse is equal to 0.2 mm of rain (optional from 0.1 to 0.5 mm). The mechanical and electrical specifications are: - Collector surface area: 1000 cmq - Collector area diameter: 420 mm - Measurements range: 180 mm/hr - Resolution: o,2 mm/imp. (opt. 0,1; 0,3; 0,4; 0,5; mm/imp.) - Accuracy: 0-1 mm/min: 1% 1-3 mm/min: 2% 3-5 mm/min: 4% 5-10 mm/min: 8% - Contact: 1 reed (opt. N.2 reed) 0,5 A/24V non inductive - Pulse duration: 100 msec.± 5 - Collector cone material: Brass - External housing material: Inox AISI30 - Tipping bucket material: Alluminium - Cable: 10 m - Weight: 6,3 kg - Power supply: /thermocover 100 W, 24 Vca/Va

At the AWS Lukla station the DQA035 Lsi-Lastem rain gauge is mounted on a 1,5 m pole. This model of Rain gauge has a 1.000 cmq collector area. The measurement device is composed of a collector cone and a double chamber bascule connected to a magnete that operates one (optional two) reed switch, which generates impulses that can be counted by external meters: each impulse is equal to 0.2 mm of rain (optional from 0.1 to 0.5 mm). The mechanical and electrical specifications are: - Collector surface area: 1000 cmq - Collector area diameter: 420 mm - Measurements range: 180 mm/hr - Resolution: o,2 mm/imp. (opt. 0,1; 0,3; 0,4; 0,5; mm/imp.) - Accuracy: 0-1 mm/min: 1%; 1-3 mm/min: 2%; 3-5 mm/min: 4%; 5-10 mm/min: 8% - Contact: 1 reed (opt. N.2 reed) 0,5 A/24V non inductive - Pulse duration: 100 msec.± 5 - Collector cone material: Brass - External housing material: Inox AISI30 - Tipping bucket material: Alluminium - Cable: 10 m - Weight: 6,3 kg - Power supply: /thermocover 100 W, 24 Vca/Va

Since 2014, the Digital Barometer PTB330, by VAISALA, is installed. Vaisala BAROCAP® Digital Barometer PTB330 is a new generation barometer, designed for a wide range of high-end atmospheric pressure measurement. -Vaisala BAROCAP® sensor -Accurate measurement -Excellent long-term stability -Added reliability through redundancy -Graphical trend display with 1-year history data -Altitude corrected pressure (QFE, QNH) -For professional use in meteorology, aviation, laboratories, and demanding industrial applications