1. EARLINET/ACTRIS IOP in summer 2012
Lucia Mona1, Michael Sicard and the EARLINET team
1CNR-IMAA Consiglio Nazionale delle Ricerche - Istituto di Metodologie per l’Analisi Ambientale, Tito Scalo (Potenza) I-85050, Italy

2. OUTLINE EARLINET EARLINET products
EARLINET efforts during summer 2012 IOP
First results
Next steps

3. European Aerosol Research Lidar Network
since 2000
27 lidar stations
- 10 multiwavelength Raman lidar stations
backscatter (355, 532 and 1064 nm) + extinction (355 and 532 nm) + depol ratio (532 nm)
10 Raman lidar stations
7 single backscatter lidar stations
comprehensive, quantitative, and statistically significant data base
Continental and long-term scale
EARLINET-ASOS

4. First tool for 4D aerosol measurements on continental scale
EARLINET: European Aerosol Research Lidar Network
First tool for 4D aerosol measurements on continental scale
Quality assurance program
Predefined measurement schedule (3 per week) → unbiased
Coordinated network observations for special events
Standardized data format
Access to data via centralized data base

5. EARLINET products
Lidar raw signal (unless of the background subtraction) provides information about particle layers (aerosol and/or clouds) and their temporal evolution.
Information about intrusion into the Planetary boundary Layer can be obtained.
Potenza, April 2010 – Eyjafjallajokull eruption
Arrival of volcanic plume and its intrusion into the PBL Mona et al., ACP2012

6. EARLINET products (2)
EARLINET standard products are the vertical profiles of aerosol optical properties:
-Aerosol backscatter coefficient
(355, 532 and 1064 nm)
-Aerosol extinction coefficient
(355 and 532nm)
-Linear particle depolarization ratio
(355 and 532 nm)
These quantities are reported in the EARLINET database in the netcdf standardized format.
Potenza, IT (40.60°N, 15.72° E, 760 m asl)
26 June 2006, 00:56-01:26 UTC

7. EARLINET products (3)
From standard products other optical properties are retrieved:
-Lidar Ratio
(355 and 532 nm)
-Angstrom exponent
(355 and 532nm)
-Backscatter related Angstrom exponent
( nm , nm)
Potenza, IT (40.60°N, 15.72° E, 760 m asl)
26 June 2006, 00:56-01:26 UTC
These quantities do not depend on the aerosol amount, but only on their microphysical properties.

8. EARLINET products (4)
Layers geometrical properties and mean and integrated values of optical properties evaluated within layers are also retrieved. These are important for microphysical retrieval and aerosol typing.
532nm: 0.31
355nm: 0.33
Lidar 51±12 sr
Lidar 532nm: 67±11 sr
Depolarization ±0.03
Angström Exponent: 0.2±0.1
Backscatter related Angstrom exponent 355/532nm: 0.6±0.2
Backscatter related Angstrom exponent 1064/532nm: 0.4±0.1

9. a daily fixed time schedule was established for the EARLINET/ACTRIS measurements during the whole EMEP/PEGASOS campaign, while intensive continuous measurements were planned in coincidence to the shorter campaign (Charmex) IOP.
Two objectives are obtained:
intensive EARLINET/ACTRIS measurements during the overlap of the 3 campaigns (large dataset of instruments measuring all around Europe)
EARLINET/ACTRIS daily measurements provide a reference point of the aerosol vertical distribution at continental scale
PEGASOS
EMEP
8 June
17 July
2 July
9 July
12 July
Charmex
Describe the interaction of your WP with other activities or WPs within the project and its integration within the overall project objectives. 9

10. MEASUREMENTS SCHEDULING
Besides the EARLINET scheduling for regular measurements (6 and 11 measurements scheduled at each station during daytime and night-time respectively), additional measurements were performed at 11 EARLINET stations during the campaign.
Stations were selected on the base of
distance from EMEP/ACTRIS sites
capability of the EARLINET stations to provide multi-wavelength extinction/backscatter profiles 10

11. Barcelona, Ispra, L’Aquila, Athens are collocated or are very close to EMEP sites participating in this campaign,
Evora, Granada, Potenza are additional important stations for dust/biomass burning events and multi-wavelength capability
Bucharest and Sofia could be important for describing pollution events typical of the Eastern Europe.
Cypros could fill the gap about extremely South-Eastern Europe
Cork could fill the gap related to the UK where more EMEP stations were operative during this campaign

12. The 11 selected stations agreed to perform the following additional measurements:
every day of the campaign (8 June – 17 July) 2 hours of measurements around the sunset.
One measurement per day could be in some sense a reference point in the comparison with the in situ measurements.
This daily temporal interval was selected for different reasons:
a) this will provide homogeneous dataset with the EARLINET regular measurements performed since May2000 at the same time-slot.
b) in night-time conditions, Raman lidar could provide extinction profiles and direct measurements of AOD.
c) after the sunset, sedimentation processes lead particles confined in the planetary boundary layer at the surface, so that a better correlation between PBL lidar and PM measurements could be possible and, on the other hand, the separation with the free troposphere is easier.

13. REPORTS and QUICKLOOK
During the campaign, images of the lidar backscatter signals collected during the campaign were promptly made freely available at
Moreover, daily reports of the observations of each station were collected and harmonized by CNR-IMAA, providing info about aerosol layering, long range transport and intrusion in the PBL.

14. EARLINET potential operationality exercise
9 July (0600 UT) – 12 July (0559 UT) → 72-hr continuous measurements
11 EARLINET / ACTRIS stations
1 non EARLINET / ACTRIS station
Organized in coincidence with Charmex campaign

15. EARLINET potential operationality exercise
Measurement protocol
Integration time: 60 min
Raw signals (P) are sent to the Single-Calculus Chain (SCC)
SCC (Single-Calculus Chain) was configured in 2 modes:
SCC-1: standardized pre-processed products (PR2)
in real time → assimilation in AQM, climate model, …
SCC-2: standardized processed optical products (extinction + backscatter in nighttime and backscatter in daytime)
in near-real time → special event monitoring, transport, impact on radiation, ...
The SCC-2 will be validated by comparing SCC-inverted and manually-inverted products. This task is ongoing.

16. MEASUREMENTS COLLECTED
On average, measurements were performed for 22 days over the 40-days period
The percentage of the performed measurements is around 80% when it is taken into account that during week-ends measurements were not assured.
ILRC-related man power problems
ILRC-related man power problems
Very cloudy conditions

17. DATA ANALYSIS
During the campaign, a preliminary analysis on the aerosol layering and potential aerosol source was performed by each lidar station.
Aerosol optical profiles from most of the involved stations are already available on the EARLINET database.

18. COLLECTED MEASUREMENTS
Saharan dust:
82 cases
Marine aerosol:
3 cases
Biomass burning:
13 cases
North America:
10 cases
Pollution:
1 case
Mixing with marine aerosol almost always for Cypros

19. COLLECTED MEASUREMENTS
Preliminary analysis permitted to identify potential cases of intrusion of FT layer into the PBL in 15 cases, while descending layers were clearly observed in 3 cases.
Additionally there are more than 40 cases with layers low in altitudes (base <0.8 km).

20. COLLECTED MEASUREMENTS
The period 2-8 July is particularly interesting because, depending on the station, different aerosol types are observed and intrusions in the PBL and layers low in altitude are observed.

21. Retroplume
Footprint
Small amount of aerosol throughout the atmospheric column
Backscatter angstrom values indicate small particles
Flexpart analysis indicate small maritime particles from the US Eastern coast

22. 1-1.6 km 1.8 -3 km Dust in FT and close to the surface
Values typical for this station dust cases
Transport from the Iberian peninsula
1-1.6 km km

26. A study case: July 05 Different situations all around Europe
Evora almost clear maritime case
Potenza polluted dust case – dust coming from Western africa travelling across Iberian peninsula
Bucharest continental/ dust from Iberian peninsula?
Satellite data ( as from CALIPSO and MODIS) will be used for investigating the variability over Europe
Source apportionment available from EMEP needed for improving aerosol typing over Europe

27. EARLINET potential operationality exercise
Synoptic meteorology and Saharan dust forecast
9 July at 12 UTC
10 July at 12 UTC
11 July at 12 UTC

28. EARLINET potential operationality exercise
72-hr quicklooks 12
9 July
10 July
11 July 12
Madrid 6 12
Potenza 6

29. Assimilation of lidar profiles in an AQM
Objectives
Use part of EARLINET / ACTRIS lidar stations to measure PR2 profiles to be assimilated in an Air Quality Model
Model:
Chemistry transport model POLAIR3D of the AQ platform Polyphemus (K. Sartelet / M. Bocquet, CEREA, France)
20 aerosol species (3 primary, 5 inorganic and 12 organic species)
5 bins over the range 0,01 – 10 µm
Domain [15ºW, 35ºE] x [35ºN, 70ºN]
Horizontal resolution 0,5º x 0,5º
14 vertical levels over the range 0 – m

30. Assimilation of lidar profiles in an AQM
Products assimilated
In a first attempt, SCC-1 (PR2) is used.
Optical products (SCC-2) might be used in the future.
The analysis is on going (PhD, LSCE / CEREA) and looks promising
Some problems encountered
Clouds prevent data assimilation
Non-corrected overlap regions have to be discarded
Assimilation of PR2: Tricky estimation of the systems’ constant
Assimilation of PR2: Validation of the aerosol model necessary
Need of an observation network of PM10 concentrations in the Med. Basin

31. FUTURE PLANS Further case studies identification
microphysical inversions for selected case studies
integration with EMEP data
comparison / integration studies with models
exploitation of this 40-days long database for aerosol variability studies