The Forni Automatic Weather Station has been installed on Forni Glacier on September 26, 2005 at 2669 m asl. This station represents the first Italian permanent above glacial AWS, that supply a big number of information about micro-meteorological conditions on surface of an Italian Alpine glacier. In particular, this station is located in the Glacial Ablation area and permits to measure both the winter accumulation and the thermal conditions and in-coming/out-coming energetic fluxes that rules the losses of glacial masses during the summer period. Geographical coordinates: - Latitude: 46° 23’ 56.0” N - Longitude: 10° 35’ 25.2” E
In 2008 expedition, at South Col was installed the DMA572 termohygrometer, that was replaced during the 2011 expedition with two DMA672 termohygrometers and one DMA033 thermometer. All these sensors are manufactered by LSI-Lastem (Italy). DMA 672 thermohygrometer is an instrument for measuring temperature and relative humidity and suitable for a continuous measurement in severe environments; in presence of deep thermal and hygrometric ranges with high sun radiant heat. An importatnt feature of this set of sensor is that the thermohygrometric sensitive element is easily replaceable, in order to have a simple and rapid ordinary maintenance and avoiding calibration. The Thermohygrometer has supported a considerable improvement, owing to a deep technical and styling development process: a fan ensures a continuos air change around the sensor in order to eliminate temperature fault caused by radiant heat. Technical characteristics for temperature: Range: -30 to 70°C Sensitive element: Pt100 Class B 1/3 DIN Sensitive element replacement: sensor replacement Accuracy (Repeatability+ Hysteresis): ±0,1°C (0°C) Resolution: n.a. Response time (Sens. Element): 10 s Thermal drift: n.a. Long term stability: <1°C year Operating temperature: -50°÷100°C Technical characteristics for relative humidity: Range: 0 to100% Sensitive element: Capacitive Sensitive element replacement: sensor replacement Accuracy (Repeatability+ Hysteresis): 1,5% (5 to 95%, 23°C) Resolution: 0,12% Response time (Sens. element): 10 s Thermal drift: Max ± 1,5% Long term stability: <1 RH% year DMA033 Thermometer is well-suited for environmental outdoor measurements, with natural or forced ventilation antiradiant shield. Technical characteristics: Range : -40 to70°C Sensitive element: Pt100 1/3 DIN-B Accuracy: ±0,1C (0°C) Repeatability: 1/5 accuracy Electric output: Pt100 ? 1/3 DIN Operating temperature: -40°to 95°C Protection (vertical pos.): IP66
In both 2008 and 2011 expeditions a CM6B Kipp&Zonen radiometer was installed at South Col. This sensor 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. CM6B technical data - Spectral range 305 to 2800 nm (50%points) - Sensitivity 9 to 15 ?V/Wm-2 - Impedance 70 to 100 Ohm - Response time 1/e 5 s, 99 % 55 s - Non-linearity <1.5 % (<1000 W/m 2 ) - Tilt error <1.5 % at 1000 W/m 2 - Operating temperature -40 to +90 °C - Temperature dependence of sensitivity _2 % (-10 to +40 °C) - Maximum irradiance 2000 W/m2 - Directional error < _20 W/m2 at 1000 W/m2 - Weight 0.85 kg - Cable length 10 m
The second italian permanent station was installed on August 14, 2007, on Dosdè Glacier. This station located at 2850 m asl permits to collect data on above glacial thermal conditions and incoming and outcoming energetic fluxes. This automatic weather station represent the highest Lombardy permanent station on glacier and its data can be comparable to those collected by AWS Forni in order to verify the effects of climate change on glacial size and micro-meteorological parameters. Geographical coordinates: - Latitude: 46° 23’ 33.944” N - Longitude: 10° 13’ 3.359” E
The CNR 4 net radiometer measures the energy balance between incoming short-wave and long-wave Far Infrared (FIR) radiation versus surface-reflected short-wave and outgoing long-wave radiation. The CNR 4 net radiometer consists of a pyranometer pair, one facing upward, the other facing downward, and a pyrgeometer pair in a similar configuration. The pyranometer pair measures the short-wave radiation. And the pyrgeometer pair measures long-wave radiation. The upper long-wave detector of CNR 4 has a meniscus dome. This ensures that water droplets role off easily and improves the field of view to nearly 180°, compared with a 150° for a flat window. All 4 sensors are integrated directly into the instrument body, instead of separate modules mounted onto the housing. But are each calibrated individually for optimal accuracy. Two temperature sensors, a Pt-100 and Thermistor, are integrated for compatibility with every data logger. The temperature sensor is used to provide information to correct the infrared readings for the temperature of the instrument housing. Care has been taken to place the long-wave sensors close to each other and close to the temperature sensors. This assures that the temperatures of the measurement surfaces are the same and accurately known. Which improves the quality of the long-wave measurements. Technical Characteristics: Spectral range: 300 to 2800 (short wave) nm Spectral range: 4500 to 42000 (long wave) nm Sensitivity: 5 to 20 µV/W/m² Temperature dependence of sensitivity (-10 ºC to +40 ºC) : < 4 % Response time: < 18 s Non-linearity: < 1 % Operating temperature: -40 to 80 °C Ventilation power (of the optional CNF 4 ventilation unit): 10 W
The third Italian permanent automatic weather station has been installed on December 17, 2007 on Gigante Glacier ( Mt. Bianco’s group). Data collected by this station permit to improve knowledge both on local micro-meteorological parameters and on periglacial and glacial conditions. Moreover, this station located at 3430 m asl permits to collect data on above glacial thermal conditions and incoming and outcoming energetic fluxes. Data collected by this station can be compared to the AWSs installed on Forni and Dosdè glaciers. Geographical coordinates: - Latitude: 45° 50' 50" - Longitude: 06° 55' 58"
In 2008 at South Col the CombiSD DNA022 sensor (LSI-Lastem, Italy) was installed. During the 2011 expedition, this sensor was replaced with a prototype (LSI-Lastem) to support with another sensor manufactured by VAISALA: WA15D7B. The WA15 is based on accurate sensors installed on a large crossarm. It is designed for demanding wind measurement applications. Three lightweight, conical cups mounted on the cup wheel, provide excellent linearity over the entire operating range, up to 75 m/s. A wind-rotated chopper disc attached to the shaft of the cup wheel cuts an infrared light beam 14 times per revolution. This generates a pulse output from the phototransistor. The output pulse rate is directly proportional to wind speed (e.g. 246 Hz = 24.6 m/s). However, for the highest accuracy, the characteristic transfer function should be used to compensate for starting inertia.
The CombiSD DNA022 Lsi-Lastem combined wind speed-direction sensor is mounted on a 5m pole. The CombiSD sensor includes, in a single apparatus, the both transducers for measuring wind speed and wind direction. Its use simplifies the installation and the plant design in respect of the sensors with separate measurements plus giving some other advantages being smaller, lighter and cheaper. The CombiSD DNA022: sensor has a direct signal output. Frequency (Hz) for wind speed and resistance (Ohm) for wind direction. the CombiSD has low power consumption, it can be used in systems with small energy availability. The technical characteristics are: - Principle of operation: 3 cups and vane anemometer - Speed sensor: Optoelectronic disk - Direction sensor: 2000 Ohm wire potentiometer / Positioning Hall effect sensor - Housing: Heavy gauge anodised aluminium - Shaft carriers: Low-torque stainless steel bearings - Protection (vertical position): IP65 - Mechanical mounting: On 48 50 mm diameter mast - Electrical outlet terminators: IP65 watertight connector - Weight (instrument with rotors): 950 gr. The Physical and operational specification are: - damage threshold > 75 m/s - operating temperature: -30°+70°C The speed measures are specified by: - Measurement range: 0-60 m/s (using transfer function) - Threshold: 0,21 m/s - Response time (63% at 5 m/s): 0.8 s - Distance constant (delay distance) at 5 m/s: 4 m - Resolution (integration time=1s): 0.05 m/s - Accuracy & Linearity: 0,1 m/s+1%VL (readout), if connected to LASTEM data loggers. The direction measures are specified by: - Measurement range: 0 ÷ 360 - Threshold: 0,15 m/s - Response time (at 5 m/s): 0,26 s - Delay distance (at 5 m/s): 1,32 m - Damping coefficient (VDI3786): 0,21 - Transfer function: Dir(°)= 355 x R(Ohm)/2000 - Resolution: 0,1 - Accuracy: 1% FS (Full scale) - Integral linearity: 0,5%
The measurement programme of the CH4 has been run by CESI RICERCA since February 1991 (at beginning by means of biweekly samplings until December 2002 and then by means of continuous measurements since January 2002). The measurements have been stopped from May 2006 to October 2007. Since 2008 the minimum temporal resolution for the mean values is based on hourly averages. Instrument: GC-FID, NIRA Venus 301 Duration of the analyses' cycle: 120 s. Detection limit: 20 ppb. The calibration measurements are realized by means of two working gas standard referred to primary standard. The working standard are systematically measured every six hours. CMDL X83 up to 2007. Since 2008 NOAA04 Scale. Convertion factor is: 1.0124. So, CMDL X83 * 1.0124 = NOAA04. In 2009, all CMDL X83 scale data have been expressed in NOAA04 scale. FLAG: "1" means "valid data". The data is considered correct but no criteria, at the moment, has been applied to identify the background data; "2" means "invalid data" (for example, instrumental problems due to the missed electrical power, incorrect calibration measurements, sampling flow incorrect and so on)
CO2 measurements by means of flasks (about every two weeks) from April 1989 to December 1997. Continuous measurements of the CO2 since March 1993. Half an hour averages are available up to December 2007. Since 2008 the minimum temporal resolution for the mean values is based on hourly averages. Since 1993, ULTRAMAT 5E NDIR Analyser, SIEMENS. Since 2008 it is also working an ULTRAMAT 6E NDIR Analyser, SIEMENS. The atmospheric CO2 concentration is measured by means of a non dispersive infrared analyser (ULTRAMAT 5E and, recently, 6E) working, respectively, in the range 350-400 ppmv (5E) and 360-410 ppmv (6E). The uncertainty of the measurement is about 0.07 ppmv. The CO2 dataset of the Plateau Rosa is composed by two partially overlapped series: the first one contains weekly data measured using flasks and extends from April 1989 to December 1997; the second one contains continuous measurements, and reports data since March 1993. The atmospheric CO2 concentration is measured by means of two non dispersive infrared analysers (ULTRAMAT 5E and, recently, 6E) working, respectively, in the range 350-400 ppmv (5E) and 360-410 ppmv (6E). The CO2 measurements are referred to the WMO X2007 international mole fraction scale. The water content in the air sampling (flasks and continuous measurements) is eliminated by means of a cryogenic cooler working at -65°C. The uncertainty of the measurement is about 0.07 ppmv. Scale and Calibration (traceability): WMO X93 scale up to 2007, now WMO X2007 scale. Measurement Calibration: The CO2 analyser of Plateau Rosa is calibrated with the NOAA-CMDL primary standards. Moreover the secondary and tertiary standards (the so-called "working standard") are acquired by SIAD and referred to the primary standard. Usually the comparison among the primary and the secondary/tertiary standard is performed every six months or, at the maximum, every year. The analyzer calibration test is realized respectively every 3 days with the secondary standard and every 6 hours with the working standard. Flag: "0" means "background data" (values identified as background data by means of our criteria of selection); "1" means "not background data" (for example, due to large variability of CO2 concentration within a half an hour or values identified as not background data by means of our criteria of selection); "2" means "invalid data" (for example, instrumental problems due to the missed electrical power, incorrect calibration measurements, sampling flow incorrect and so on).