WP2- NA2: Remote sensing of vertical aerosol distribution ... · Deliverable WP2 / D2.11 (M42) WP2- NA2: Remote sensing of vertical aerosol distribution Deliverable D2.11: Report

Deliverable WP2 / D2.11 (M42)

WP2- NA2: Remote sensing of vertical aerosol distribution Deliverable D2.11: Report on 2nd IC campaign


Table of Contents1 Introduction.........................................................................................................................................2

2 MUSA (reference lidar system)............................................................................................................4

3 Inter-comparison MALIA - MUSA 14-18 October 2013........................................................................63.1 MALIA...........................................................................................................................................6

3.2 Day time intercomparison 17. October 2013................................................................................93.3 Night time intercomparison 17. October 2013...........................................................................11

4 Inter-comparison Lecce lidar - MUSA 21-25 October 2013................................................................14

4.1 Lecce lidar system.......................................................................................................................14

4.2 Intercomparison 23. October 2013.............................................................................................17

5 Inter-comparison Minsk MSTL-2 with LMR 30. 09. 2013....................................................................20

1 Introduction

Figure 1.1 EARLINET lidar stations (2014)

The many lidar systems within EARLINET are all home- or custom-made, and hence very different.From small, portable, single wavelength lidar systems to huge, stationary, multi-channel lidar sys-tems with several telescopes to better cover the far and near ranges. Furthermore, as most lidar sys-tems are research instruments, they are continuously developing and changing. A common qualityassurance strategy can not cover all the details of all systems, but must focus on some main paramet-ers.

One can evaluate the quality of a measurement instrument by either comparing a measured quantity


with a known quantity like a standard target, or one compares with the outcome of a standard meas -urement instrument of the same target. For lidar systems both standards do not exist – neither astandard target, nor a standard instrument.

In the frame of EARLINET-ASOS the activity NA2.2 (Quality Assurance) had been established to de-velop tools for testing the accuracy and the temporal stability of the quality of the lidar systems.

The developed internal check-up tools can be applied to all lidar systems. The near range limit (over-lap function) is checked with the telecover test, and the far range capability and accuracy with theRayleigh fit test. The trigger-delay (zero-bin) test verifies the correct range correction, which is veryimportant in the near range below about 1 km range, and the dark measurement and pulse gener-ator measurements deal with signal distortions. These tests are performed yearly with every lidarsystem and with every signal channel, and the results are documented in yearly ACTRIS "reports oninternal hardware quality checks".

Regarding the overall quality check, direct lidar inter-comparisons are scheduled during ACTRIS for alllidar systems not checked in this way within the last five years. For direct lidar inter-comparisons twoor more lidar systems are located close to each other to measure the same atmosphere during thesame time periods. Although the lidars are located close to each other, the measured atmosphericvolume is never exactly the same, and the intercomparison between systems is often complicated bythe intrinsic differences of the systems (at least one must be moveable), which are e.g. differentmeasurement ranges, different sampling rates, and different analysis software packages. Sometimesthe weather conditions during the limited intercomparison campaigns can be unfortunate, so thatthe inter-compared signals cannot reveal the desired details. Furthermore, such direct lidar inter-comparisons are costly regarding man power and money, and cannot be repeated regularly.

Three transportable EARLINET lidar systems are currently available as reference lidar systems, whichhave shown their outstanding quality and temporal stability in several inter-comparisons. These arethe MULIS and POLIS lidar systems of the Ludwig-Maximilians-University of Munich, Germany, andthe MUSA lidar system of the Consiglio Nazionale delle Ricerche - Istituto di Metodologie per l'AnalisiAmbientale, Potenza, Italy.


2 MUSA (reference lidar system)The MUSA lidar system of the Consiglio Nazionale delle Ricerche, Istituto di Metodologie per l'AnalisiAmbientale (CNR-IMAA) in Potenza / Italia was selected as an EARLINET reference lidar system duringthe direct intercomparison of twelve EARLINET lidar systems during EARLI09 [Wandiger et al., EAR-LINET instrument intercomparison campaigns: overview on strategy and results, Atmos. Meas.Tech.Discuss., in preparation, 2014]. MUSA signals at all wavelengths showed deviations <5% from thewheigthed mean of all the lidar sytems.

Figure 2.1 The MUSA lidar in the mobile container.

Figure 2.2 Optical setup of the MUSA lidar.


Table 2.1 Specifications of the MUSA reference lidar from the EARLINET handbook of instruments.


3 Inter-comparison MALIA - MUSA 14-18 October 2013The MALIA lidar system of the Consorzio Nazionale Interuniversitario per la Scienze Fisiche della Ma-teria (CNISM) in Napoli/Italia was inter-compared with the MUSA referece lidar of the ConsiglioNazionale delle Ricerche, Istituto di Metodologie per l'Analisi Ambientale (CNR-IMAA) during themeasurement campaign in Napoli – CNISM NALI13 (Napoli Lidar Intercomparison 2013) between 14-18 October 2013.

Figure 3.1 The MALIA and MUSA lidar systems in their containers.

3.1 MALIA

Table 3.1 Main specifications of the MALIA lidar.

MALIA MUSA


Figure 3.2 Optical setup of the MALIA lidar.


Table 3.2 Full specifications of the MALIA lidar from the EARLINET handbook of instruments.


3.2 Day time intercomparison 17. October 2013

Figure 3.3 Quicklook of the atmospheric situation during the daytime intercomparison period (red rectangle) on 17.10.2013.

Figure 3.4 Attenuated backscatter signals and relative deviation of the MALIA from the MUSA signal at 355 nm on 17.10.2013 between 11:45 and 12:04 UT.


Figure 3.5 Attenuated backscatter signals and relative deviation of the MALIA from the MUSA signal at 532 nm (parallel polarization) on 17.10.2013 between 11:45 and 12:04 UT.

Figure 3.6 Attenuated backscatter signals and relative deviation of the MALIA from the MUSA signal at 532 nm (perpendicular polarization) on 17.10.2013 between 11:45 and 12:04 UT.


3.3 Night time intercomparison 17. October 2013

Figure 3.7 Quicklook of the atmospheric situation during the nighttime intercomparison period (red rectangle) on 17.10.2013.

Figure 3.8 Attenuated backscatter signals and relative deviation of the MALIA from the MUSA signal at 355 nm on 17.10.2013 between 23:03 and 00:06 UT.


Figure 3.9 Attenuated backscatter signals and relative deviation of the MALIA from the MUSA signal at 532 nm (parallel polarization) on 17.10.2013 between 23:03 and 00:06 UT.

Figure 3.10 Attenuated backscatter signals and relative deviation of the MALIA from the MUSA signalat 532 nm (perpendicular polarization) on 17.10.2013 between 23:03 and 00:06 UT.


Figure 3.11 Attenuated backscatter signals and relative deviation of the MALIA from the MUSA signalat 387 nm on 17.10.2013 between 23:03 and 00:06 UT

Figure 3.12 Attenuated backscatter signals and relative deviation of the MALIA from the MUSA signalat 607 nm on 17.10.2013 between 23:03 and 00:06 UT


4 Inter-comparison Lecce lidar - MUSA 21-25 October 2013The Lecce lidar system of the University of Salento, Lecce, Italia, was inter-compared with the MUSAreferece lidar of the Consiglio Nazionale delle Ricerche, Istituto di Metodologie per l'Analisi Ambien -tale (CNR-IMAA) during the measurement campaign in Lecce (Lecce Lidar Intercomparison 2013) be-tween 21-25 October 2013.

Figure 4.1 The Lecce lidar in the University building with roof window and the MUSA lidar systems in the container.

4.1 Lecce lidar system

Table 4.1 Main specifications of Lecce lidar system.

MUSA LECCE system


Figure 4.2Optical setup of the Lecce lidar system.


Table 4.2 Full specifications of the Lecce lidar from the EARLINET handbook of instruments.


4.2 Intercomparison 23. October 2013

Figure 4.3 Quicklook of the atmospheric situation during the intercomparison period (red rectangle) on 23.10.2013.

Figure 4.4 Attenuated backscatter signals and relative deviation of the Lecce lidar from the MUSA sig-nal at 355 nm on 23.10.2013 between 20:39 and 21:06 UT. Calculated molecular backscatter signal from radiosonde data Brindisi airport 00 UT for comparison.








5 Inter-comparison Minsk MSTL-2 with LMR 30. 09. 2014The Stepanov Institute of Physics (IPNASB) in Minsk, Belarus, operates two lidar systems: the mobile LMR, and the stationary MSTL-2. The LMR-mobile lidar participated in the EARLI09 intercomparison of twelve lidar systems in Leipzig, Germany, in 2009. The both lidars were intercompared in Minsk on30.09.2014 16:00 – 16:07.

Table 5.1 Full specifications of the MSTL-2-lidar from the EARLINET handbook of instruments.


Table 5.2 Full specifications of the LMR-mobile lidar from the EARLINET handbook of instruments.


Figure 5.1 Attenuated backscatter signals (left) and relative deviation (right) between the LMR and MSTL-2 lidar systems at 355 nm on 30.09.2014 between 16:00 and 16:07.



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WP2- NA2: Remote sensing of vertical aerosol distribution ... · Deliverable WP2 / D2.11 (M42) WP2- NA2: Remote sensing of vertical aerosol distribution Deliverable D2.11: Report