long-term earlinet dust observationsdustworkshop2013.enea.it/presentations/day2_1720_mona... ·...

7th

International Workshop on Sand/Duststorms and Associated Dustfall, ESRIN, Frascati, 2-4 December 2013

Long-term EARLINET dust observations

Lucia Mona,V. Amiridis, A. Amodeo, G. D’Amico, A. Hiebsch, N.

Papagiannopoulos, A. Papayannis, M. Sicard, U. Wandinger, A. Comeron ,

and G. Pappalardo

CNR-IMAA Consiglio Nazionale delle Ricerche - Istituto di Metodologie per l’Analisi Ambientale,

Tito Scalo (Potenza) I-85050, Italy

[email protected]

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● 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

European Aerosol Research Lidar Network

www.earlinet.org

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EARLINET is an optimal observation tool for Saharan dust events

- dust profiling

- stations located in Southern Europe

- high performance lidar stations

- coverage at continental scale to study transport and modification processes

- a suitable observing methodology has been established within the network

forecasting scheme [DREAM, Skiron]

alert (warnings: 24-48 h)

- use of air-mass back-trajectory analysis [German Meteorological Service

(DWD/GME Model) and NOAA HYSPLIT] and satellite data analysis

(EP/TOMS AI, SeaWiFS AOT, NOAA/AVHRR AOT, MODIS AOT,

CALIPSO)

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EARLINET measurements

Saharan dust

A suitable observing methodology has been established within the network

for studying Saharan dust events.

Measurements are performed in correspondence of alerts based on the

operational outputs of the DREAM (Dust REgional Atmospheric

Model), and the Skiron models distributed to all EARLINET stations by

the NTUA (National Technical University of Athens) group

The alerts are diffused 24 to 36 hours prior to the arrival of dust aerosols

over the EARLINET sites.

Typically runs of measurements longer than the typical 3-hour observations

performed for the EARLINET systematic measurements are performed

at the EARLINET stations in order to investigate the temporal

evolution of the dust events.

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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, 19-22 April 2010 – Eyjafjallajokull eruption

Arrival of volcanic plume and its intrusion into the PBL Mona et al., ACP2012

EARLINET products

Quicklook images typically avaialble through a link from www.earlinet.org

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Example of EARLINET measurements

FT layer

PBL

AODUV=0.26

AODVIS=0.19

AODUV=0.17

AODVIS=0.11

SUV=51±10 sr

SVIS=53±8 sr

Å = 0.9 ± 0.2

δ=0.12±0.03

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All Climatol Calipso Saharan Volcanic DiurnalCycle Cirrus Others

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5000

10000

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EARLINET database

Devoted database in a standardized NetCDF format (CF compliant dataformat).

EARLINET database is organised into 10 categories (climatology, saharan, volcanic, forest fires , calipso, etc)

3 level of data availability: internal (1 year From data acquisition)

External freely available www.earlinet.org and

ACTRIS data portal

DOI database with quality checked files in publication

2000 2002 2004 2006 2008 2010 2012

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Systematic dust observations over Europe

First study on the impact of Saharan dust on European aerosol content during the

first period of operation of the network (2000–2002) Papayannis et al. JGR 2008

North and Western regions show low dust transport activity

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AOD at 351–355nm inside the dust lofted layers

Values in 0.1 -0.25 range with a standard deviation of the order of 20–100% that

clearly indicates the high variability of the dust outbreaks over Europe.

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S values ranged between 38 and 60 sr inside the dust layer,

while their standard deviation is of the order of 20–30%.

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Typical values of intensive properties

northern Europe

linear particle depolarization ratio values range from 10 to 25% at

532nm

approximately constant A° (β355/532) values (−0.5 to 1)

approximately constant S values (30 to 80 sr)

Southern Europe

S (20 to 100 sr) with high variability

A° (β355/532) (−0.5 to 3) highly variable

linear particle depolarization ratio values as high as 35 % at

532nm

Cyprus: a new EARLINET station for Arabian dust

S at 532 nm between 34t – 39 sr for dust event in 2011

28%–35% linear particle depolarization ratio Mamouri et al., GRL 2013

Papayannis et al. JGR 2008

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Dust: mixing and typing

Among cases of Saharan dust intrusions observed over EARLINET in May 2008–

October 2009 period, we found that:

• only 12% of cases can be considered pure Saharan dust cases

• 88% of the cases, mixing of dust with different aerosol types cannot be excluded.

The mixtures of dust, pollution, and marine aerosol are the most frequently obtained.

All mixtures lie on nearly straight

connecting lines between their

constituents.

Such a clear behavior is not necessarily

expected and could indicate external

mixtures.

It seems possible defining

“trajectories” between pure aerosol

types in a multi-dimensional

parameter space on which the

mixtures occur.

Wandinger, Executive summary ESTEC, 2011

Satellite validation & exploitation

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Evaluation of CALIPSO Lev 2 aerosol opticla profiles within 100 km of distance from

EARLINET stations. Leipzig, Evora, Granada, Napoli and Potenza selected for

having the largest single station databases.

A total amount of about 150 extinction comparison is achieved.

Mona et al., in preparation

In the middle altitude range (2.5-5km), Scal=41.1 sr vs Sear=47.7sr with 7 sr

bias. This is probably due to the Saharan dust occurrences at this altitude

range and stations.

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Observations (airborne in situ + lidar ) performed in pure dust in the Saharan

dust plume over Southern Morocco and Cape Verde during SAMUM campaign

showed that:

• in the CALIPSO retrieval of backscatter coefficients, the a priori lidar

ratios from the lookup table of 40 sr used for dust represents an effective

value that accounts well for the reduced attenuation caused by multiple

scattering

• the CALIPSO extinction values calculated by multiplying the backscatter

values with the effective lidar ratio, a systematic underestimation of

extinction, and thus optical depth, by 10%–40% is caused

Wandinger et al GRL 2011

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Models evaluation

A method for a quantitative evaluation of the dust modeled profiles is explored

starting from the Potenza (Italy) station selected as the site with the largest database

of dust profiles.

Comparison for May 2000 – June 2012 period between lidar observations and BSC-

DREAM8b forecasts over Potenza.

Potenza EARLINET file : typically 30min as temporal resolution –

vertical resolution 60 m for backscatter –

240 m for extinction profiles

BSC-DREAM8b profiles: 3h as temporal resolution

Only cases in which a Saharan dust layer is identified in the lidar profiles are

compared.

Comparison is performed in terms of dust layer geometrical properties (base, top,

extension and center of mass) and of dust extinction properties.

Mona et al ACPD 2013

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Models evaluation

Geometrical features of dust layer is well described by the model in terms of center

of mass.

Good correlation between optical properties and concentration profiles apart from

cases with low dust amount (AOD

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Models evaluation

Future plans

The methodology and software for this comparison will be used to extend the study to

all EARLINET stations but also to other models.

BSC-DREAM8b and DREAM8-SEEVCCC

Granada Potenza Napoli Athens Thessaloniki and Leipzig are selected for temporal

coverage and geographical position.

Currently in progress, the comparison of LIRIC mass concentration profiles with

models.

Binietoglou et al POSTER n. O4

BSC-DREAM8b

predicts

exceptionally well the

start of the event.

After 5 days the

prediction is not so

good.

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Instruments synergy

LIRIC integrates co-located sun-photometer and lidar measurements.

Integration with in situ measurements was stimulated by the ACTRIS Summer 2012

campaign.

ACTRIS and EMEP have worked close together to coordinate this intensive field

campaign mainly devoted to study Saharan dust particles.

The observation period (8 June – 17 July) was appropriately scheduled for taking

the most from the potential cooperation with other CHARMEX and PEGASOS

measurement campaigns which took place in selected regions of Europe in the same

period.

Papagiannopoulos et al POSTER n. O14

Two intense African dust outbreaks were observed: 18-21June, and 28

June – 6 July.

EALINET stations situated in the Mediterranean basin, identified the

plume as it propagated from the source region to Spain and then towards

Italy.

Agreement with mineral dust analyses performed by EMEP stations

(EMEP status report 2/2013), on the levels and composition of PM10.

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NRT data and data assimilation

EARLINET operationality exercise:

• 72h of continouos measurements

• Range corrected signals were assimilated in an Air Quality Model

• A centralized and automatic procedure for ldiar data pre-processing and

analysis was used (Single Calculus Chain - SCC)

• Chemistry transport model POLAIR3D of the AQ platform Polyphemus (K.

Sartelet / M. Bocquet, CEREA, France)

Wang et al in preparation

PM10:

No significant improvement on the

whole Europe

AOD:

1:1 better correlation when lidar data

were assimilated

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Future plans

EARLINET long term observations will be used for systematic models evaluations

Synergistic approach with other remote sensing sensors will be exploited for ICN and

NWP studies

After first promising results, NRT lidar data and assimilation will be investigated

Intensive properties vs mixing and source regions are under investigation.

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Thanks for your attenction!!!

The online abstract submission closes on 20th December.

long-term earlinet dust observationsdustworkshop2013.enea.it/presentations/day2_1720_mona... ·...

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