Successful flight with the LPMA/DOAS payload on 18 February

by Klaus Pfeilsticker, Univ. of Heidelberg

A 100 Z balloon carrying a reduced in weight (465 kg) and size LPMA/DOAS payload was launched succesfully by CNES at 12:15 UT on February 18, 1999. Solar absorption measurements were performed by the FT-IR (FourierTransform-InfraRed Spectrometer ) and DOAS (Differential Optical AbsorptionSpectrometer) instruments during balloon ascent from 3 km up to the float altitude at about 31 km. Sunset measurements were then performed at float until final loss of sun for tangent altitudes in the 10 km range. The balloon separation took place over Russia, as planned. The payload has been recovered safely and brought back to ESRANGE by the Russian recovery team.

The spectrometers onboaard carried out simultaneous profile mesurements of HCl, ClONO2, CH4, N2O, HNO3, NO2, NO, O3 and HF in the infrared spectral range and of O3, BrO, IO, NO2, O4 and OClO in the UV/vis spectral range. The preliminary data retrieval shows that the observations were made within a denoxified and chlorine activated vortex (see Figure 2).

Figure 1. The LPMA/DOAS team study the data being transmitted from the balloon during the flight.
Click on image to see it in higher resolution.
Figure 2. Map of potential vorticity over Northern Fenno-Scandia. The white curve shows the trajectory followed by the balloon. The black lines show the optical paths of the observations. The numbers indicate the solar zenith angle.

Click on the plot to see it in high resolution.

This page was updated on 21 March 2000 by Geir Braathen, NILU.