MULIS and POLIS quicklooks

The quicklooks are just meant to give a fast overview over the vertical aerosol distribution from the subsequent 10 s averaged, attenuated backscatter profiles. The retrieval of backscatter and extinction coefficients and linear depolarisation ratio needs more work.
Such data are sometimes added later below the quicklooks together with additional information from other sources like sunphotmeter data from Munich, CALIPSO lidar profiles or dust model predictions etc..

Why does the signal strength changes with time, sometimes quite abruptly?
Often the laser power changes or system parameters are optimized during the measurements, or calibration measurements are done with system parameters adjusted to that. Hence the color scale and the overlap range can change over the plot.
There can be breaks in the time scale of the MULIS plots when meaurements had been stopped over a certain time (e.g. 06.Apr. 2009, 13:37 - 16.19 UTC). The normal step in the time ticks is 10 min 20 sec.  Every longer periode indicates measurement breaks.
Sometimes all profiles are normalized to a certain altitude range where we assume rather constant integrated backscatter in order to get a "smoother" picture when system parameters change much over time (indicated by "Norm XX.X to YY.Y" in the footer; e.g. 06.Apr. 2009, 13:37 - 16.19 UTC).
In some plots measurements under different elevation angles are combined, which can be identified by the note "Elevation variable" in the footer (see e.g. 08.02.2008). 


The measurements are mainly performed in the frame of the regular EARLINET measurements or during CALIPSO overpasses for validation purpose of the CALIOP lidar on this satellite in Munich (POLIS) and Maisach (MULIS).

Volker Freudenthaler, March 2007


Who took the measurements? (since the start of the quicklooks in 2007)

Alexander Geiß
Andrew Reigert
Andy Platis
Bettina Richter
Franziska Schnell 
Lukas Schmidt 
Markus Eifried
Martin Köhler
Mathias Pietzka
Matthias Wiegner
Sebastian Müller
Silke Groß 
Stefanie Meul 
Theresa Schadow
Tobias Sirch
Volker Freudenthaler

These measurements had not been possible without the continuous contributions from
Anton Lex (mechanical workshop)
Dieter Rabus (electronics)
Heinrich Quenzel (initiator)
Meinhard Seefeldner (mechanical and electronic design, engineer for everything)
and several others.

---

Notes:

25.04.2011
The height scale of the depolarization quicklooks until today is 52.5 m too high (MULIS). In other words: the depolarization structures appear 52.5 m higher than the backscatter structures. This is corected now.