GuMNet includes sensors for the monitorization of atmopheric and surface and subsurface variables. Some details are provided below.
The GuMNet facility includes 10 real time automatic weather stations following the quality criteria of the WMO. A GPRS connection is established between all the remote stations and a central server. This configuration allows to download the recorded data once a day and to verify the healthy status of the instrumentation, hence minimizing the loss of data. The standard GuMNet station includes: an alpine wind monitor (DVV), an air temperature and humidity sensor (THR), ultrasonic snow height sensor (SAN), a 4 component net radiation sensor (SNR) and a rain gauge (PLM) specially designed for snow measurements.
Surface and Subsurface features
The sensors for monitoring temperature and humidity both in surface and subsurface are an important feature of the GuMNet network. Temperature sensors were placed at different depths through 15 boreholes distributed all over the stations with two main different configurations: 2 meters detph (BRH 2) and 20 meters deep (BRH 20). Both are encased with PVC to ensure that the inner space is sealed. Inner space is filled with silicone oil to prevent freezing effects, avoid internal convection process and guarantee the thermal stability along the tube, this fact is essential to ensure reliable measurements in all depths.
Additionally, 9 trenches (SHS) have been dug and distributed in 8 sites. This field acctivities allowed characterizing soil horizons at each site, taking samples at 5 cm depth intervals as well as introducing sensors for monitoring soil temperature and moisture at various depths. The analysis of the samples together with the soil horizons characterization will provide valuable metadata about biological, physical and chemical soil properties. This information will be relevant for interpreting the recorded data.
Anemometric, turbulence and soil respiration towers.
The GuMNet infraestructure includes two anemometric stations, where temperature (TA) and wind (VV) are measured jontly with an integrated CO2/H2O Open-Path Gas Analyzer and a 3D Sonic Anemometer IRGASON ® (CO2 + AS3). Thanks to the precision of the 3D sonic anemometer, high-frecuency (20Hz) variations in the wind field will be available also. This will allow for monitoring air dynamics and H20 vapor and CO2 fluxes between 0 and 10 meters high turbulent processes responsible for soil respiration and gas exchange, such as turbulence CO2 and H2O vapor fluxes take place.
EG010-La Herreria is a fixed anemometric tower with wind speed (VV) and air temperature (TA) sensors at three different heights. Likewise, the station includes the standard WMO meteorological measurements as other GuMNet sites and also surface and subsurface instrumentations: two experimental boreholes (2 ans 20 meters depth) and tempererature and humidity sensors at three different depths. A complementary twin portable station, EG901-Portatil is also operational for comparison purposes at this site or for use in intensive measurement campaigns elsewhere.