Hübner, J*; Olesch, J; Meixner, FX; Falke, H; Foken, T: Measuring of characteristical atmospheric quantities at a clear-cutting with a horizontal mobile measuring system
Poster, 3rd iLEAPS Science Conference, Garmisch-Partenkirchen, Germany: 2011-09-18 - 2011-09-23

The differences respectively the gradients of characteristical atmospheric quantities are immense at the transition from a dense forest to an open clear-cutting, with heavy effects on transfer and chemical processes. In future forest ecosystems, the heterogeneity will increase due to winds and pests with significant influences on a climate system, because it must be assumed that these heterogeneities increase the loss of trace gases. An important issue of this investigation is the horizontal coupling of turbulent eddies [1] between the forest and the clear-cutting for turbulent conditions and the movement of air parcels for the very stable case. Therefore the trace gas measurements should be the right quantities to show possible effects. To achieve more information of horizontal gradients in this heterogeneous forest ecosystem, we build a horizontal mobile measuring system (HMMS). During the third intensive observation period (IOP-3) of the EGER (ExchanGE processes in mountainous Regions) project in June/July 2011, the HMMS was installed vertically to a forest edge near the FLUXNET site Waldstein-Weidenbrunnen (DE-Bay), located in a low mountain range in the north east of Bavaria, Germany, the Fichtelgebirge Mountains (Figure1). The path of the HMMS leads 75 m through a dense spruce forest and 75 m over a big clear-cutting, caused by hurricane “Kyrill” in the year 2007. The HMMS measures in addition to meteorological quantities (temperature, humidity and short/long wave radiation) also trace gases (ozone and carbon dioxide). The HMMS works completely automatic on a model railroad system from LGB (scale: 1:22.5) installed on a wooden construction one meter above the ground. Determination of position, control of speed and the turnovers are realized by a software and a barcode scanner with barcodes each meter. A PC in combination with a National Instruments USB-6211 (16-bit analog i/o controller) is responsible for data acquisition of each sensor and for data logging. References [1] Serafimovich et al., 2011, Boundary-Layer Meteorol., 140, 429-451.

last modified 2011-09-26