The Field Experiment SATURN (2002)

The SATURN ("Strahlung, vertikaler Austausch, TURbulenz und Partikel-Neubildung" field experiment (Stratmann et al., 2003 & Siebert et al., 2004) about new particle formation in the planetary boundary layer was conducted at the IfT field research station in Melpitz, about 40 km northeast from Leipzig. The experiment took place from 27 May to 14 June 2002. Simultaneous ground-based and tethered balloon-borne measurements were performed, including meteorological parameters, particle number concentrations and size distributions, gaseous precursor concentrations and SODAR and LIDAR observations. New-particle formation was observed under different boundary layer conditions; a summary is given in Stratmann et al., 2003. The special case of increased number concentrations of ultrafine particles in the size range between 5 and 10 nm around the nocturnal inversion layer is discussed in Siebert et al. 2004. From these observations two typical vertical profiles measured with the balloon-borne ACTOS are shown in Fig. 1 and 2. In Fig. 1-I the potential temperature with standard deviation, in Fig. 1-II the absolute humidity with standard deviation, and in Fig. 1-III the number concentration of the ultrafine particles and the number concentration of particles between 10 and 1500 nm are shown as a function of the barometric height. The data was sampled on May 30, 2002 between 06:18 and 06:38 UTC during an ascent. A significant increase of ultrafine particles was observed around the temperature inversion between 300 and 600 m. Figure 2 depicts the same parameters but sampled between 06:42 to 07:22 UTC during the following descent. Ultrafine particles were formed around the inversion and finally mixed down to the ground level. For further details and discussion refer to Siebert et al., 2004.


SATURN1 SATURN2
Figure 1: Vertical profiles made during the SATURN Experiment on May 30, 2002 during an ascent between 06:18 and 06:38 UTC. Part I shows the potential temperature and standard deviation, part II shows the absolute humidity and standard deviation, and part III shows the particle number concentration of ultrafine particles (between 5 and 10 nm) and the number concentration of particles between 10 and 1500 nm. Figure 2: Profiles of same parameters as in Fig. 1. but for the following descent between 06:42 to 07:22 UTC.

Last Modifications: 2006-05-18