AMFIC final meeting

LAP/Auth validation activities

Dimitris Balis & MariLiza KoukouliLaboratory of Atmospheric PhysicsAristotle University of Thessaloniki

Task 3.1: Validation of satellite-retrieved aerosol properties over a wide range of geolocations over Europe and China using ground-based results from the AERONET network.

Task 3.2: Validation of satellite-retrieved aerosol properties over the city of Thessaloniki using a dedicated ground-based Brewer spectrophotometer.

Task 3.3: Validation of satellite-retrieved SO2 pollution fields over a wide range of geolocations over Europe and China where ground-based Brewer spectrophotometers exist.

Task 3.4: Validation of the satellite-retrieved SO2 pollution fields over the city of Thessaloniki using the coincident to the satellite overpass ground-based Brewer spectrophotometers measurements.

Task 3.5: Validation of satellite-retrieved tropospheric O3 slant columns over selected Chinese and European stations that include ozone sondes.

Work package 3: Validation of aerosol properties, SO2 and O3 amounts

Task 3.1: Validation of satellite-retrieved aerosol properties over a wide range of geolocations over Europe and China using ground-based results from the AERONET network.

With Anu-Maija Sundström, Pekka Kolmonen and Gerrit de Leeuw

FMI, Helsinki, Finland

Task 3.1: Validation of satellite-retrieved aerosol properties over a wide range of geolocations over Europe and China using ground-based results from the AERONET network.

Aeronet data http://aeronet.gsfc.nasa.gov AERONET provides globally

distributed observations of spectral aerosol optical depth (AOD), inversion products, and precipitable water in diverse aerosol regimes. Aerosol optical depth data are computed for three data quality levels: Level 1.0 (unscreened), Level 1.5 (cloud-screened), and Level 2.0 (cloud-screened and quality-assured).

AOD at 675nm & associated Angstrom Exponent

AATSR data provided by FMI

AODs from AATSR at 555, 659 & 1060nm. Over EUROPE for year 2003:

One aerosol model tested: non-absorbing fine particle type & non-absorbing coarse particle

type. 30 AATSR European overpasses with AERONET level 1.5 data. 22 AATSR European overpass with AERONET level 2.0 data.

Over CHINA for year 2008: Four aerosol models tested:

CH01_CH02 : sulphate, fine mode & mineral, coarse DPfi_NeCo: dirty pollution, fine & neutral, coarse IPfi_NeCo: industrial pollution, fine & neutral, coarse IPfi_CH01: industrial pollution, fine & sulphate, fine

11 AATSR China overpasses with AERONET level 1.5 data. 4 AATSR China overpass with AERONET level 2.0 data.

Europe, coincidences with level 1.5 Aeronet

Example : Lecce University, Aeronet level 2.0 for 555 nm

Europe, all coincidences with level 1.5 Aeronet for 555nm

Europe, all coincidences with level 2.0 Aeronet for 555nm

China, coincidences with level 1.5 Aeronet

CH01_CH02 : sulphate, fine mode & mineral, coarse

DPfi_NeCo: dirty pollution, fine & neutral, coarse

IPfi_NeCo: industrial pollution, fine & neutral, coarse

IPfi_CH01: industrial pollution, fine & sulphate, fine

Task 3.2: Validation of satellite-retrieved aerosol properties over the city of Thessaloniki using a dedicated ground-based Brewer spectrophotometer.

Task 3.2: Validation of satellite-retrieved aerosol properties over the city of Thessaloniki using a dedicated ground-based Brewer spectrophotometer

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MODI S/ Terra and MODI S/ Aqua vs BREW ER 30 m inute coincidences

E quation Y = 0 .8 98 * X + 0 .113N um ber o f data po in ts used = 311

A verage X = 0 .396 & A verage Y = 0 .469R -squared = 0 .576

E quation Y = 0 .8 52 * X + 0 .1636N um ber o f d ata po in ts used = 213

A verage X = 0 .394 & A verage Y = 0 .50 0R -squared = 0 .429

Koukouli et al., Comparisons of satellite derived aerosol optical depth over a variety of sites in the Southern Balkan region as an indicator of local air quality, Proc. SPIE Int. Soc. Opt. Eng. 6745, 67451V (2007)

Task 3.2: Validation of satellite-retrieved aerosol properties over the city of Thessaloniki using a dedicated ground-based Brewer spectrometer & AERONET level 1.5 measurements

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Equation Y = 0.706 * X - 0.102Num ber of data points = 22

Average X = 0.56 & Average Y = 0.30R -squared = 0.85

Task 3.3: Validation of satellite-retrieved SO2 pollution fields over a wide range of geolocations over Europe and China where ground-based Brewer spectrophotometers exist.

With Jos van Geffen and Michel Van Roozendael,

BIRA, Brusells, Belgium.

Task 3.3: Validation of satellite-retrieved SO2 pollution fields over a wide range of geolocations over Europe and China with Brewer spectrophotometers.

Three in China

& Two in Korea

& One in Hong-Kong

How is total SO2 extracted from the Brewer measurements

S0 = the instrumental extraterrestrial constant for SO2

S = a linear combination of the log of the measured light intensities at 306.3 nm, 316.8 nm and 320.1 nmΔβ′ = the same linear combination of Rayleigh scattering coefficients at the above mentioned wavelengthsm = the number of atmospheres along the incident light pathΔα = a linear combination of the Ο3 absorption coefficients

μ = the effective pathlength through Ο3

Δα′ = α linear combination of the SO2 absorption coefficientsμ′ = the effective pathlength through SO2

302

OmSSSO

Example: Hohenpeissenberg, Europe, 47.80°North

Northern [upper] & Southern [lower] latitudes around Beijing, 100km – The MaxDOAS results

Investigating further into the South-North gradient issue – The MaxDOAS results

Task 3.3: Validation of satellite-retrieved SO2 pollution fields over a wide range of geolocations over Europe and China with Brewer spectrophotometers.

Summer-winter signal in the monthly mean scatter plots

Task 3.4: Validation of the satellite-retrieved SO2 pollution fields over the city of Thessaloniki using the coincident to the satellite overpass ground-based Brewer spectrophotometers measurements.

With Jos van Geffen and Michel Van Roozendael,

BIRA, Brusells, Belgium.

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Task 3.4: Discussion of the Thessaloniki Brewer total SO2 : corrected & uncorrected jumps in the time series

Task 3.4: Un-corrected [left] vs corrected [right] Brewer spectrometer histograms.

Task 3.4: Validation of the satellite-retrieved SO2 pollution fields over the city of Thessaloniki using the coincident to the satellite overpass ground-based Brewer spectrophotometers measurements.

Task 3.5: Validation of satellite-retrieved tropospheric O3 slant columns over selected Chinese and European stations that include ozonesondes.

With Ronald van der A, Olaf Tuinder and Jacob van Peet,KNMI, De Bilt, Netherlans

Task 3.5: Validation of satellite-retrieved tropospheric O3 slant columns over selected Chinese and European stations that include ozone sondes.

The datasets GOME-2 : tropospheric O3 columns [TOC]

provided from 01.05.2007 to 31.12.2008 Ground-based: 29 ozonesonde stations

have coincident measurements within the GOME2 time frame. Since so few data points exist, all available ozonesondes are used in this study. The ozonesondes provide high resolution

vertical ozone profiles.

The methodology The comparison:1. The ozonesonde profile is convolved into a new

profile using the apriori ozone profile and averaging kernels that were used in the GOME-2 analysis as follows: X’OZONESONDE = XAPRIORI + AK * [XOZONESONDE-XAPRIORI]

2. This convolved profile is then integrated up to the tropopause level to a new TOC.

3. The new convolved TOC is compared to the GOME-2 TOC.

Example – Hohenpeissenberg

Task 3.5: Validation of satellite-retrieved tropospheric O3 slant columns over selected Chinese and European stations that include ozone sondes.

O3-Saf GOME2 validation of tropospheric O3 profilesUTLS consistent overestimationWork of: Andy Delcloo, Royal Meteorological Institute of Belgium

Conclusions Total AOD from AATSR & AERONET:

China: Model using industrial pollution, fine & neutral, coarse particles seems to work best.

Europe: Model works well when constricting comparison to results with small variance.

Total SO2 from Sciamachy & Brewers: Sciamachy often at the noise level. Calibration issues with the Brewers. Some common seasonal variability observed, especially

for the winter months. Tropospheric Ozone from GOME2 &

Ozonesondes: Constant offset of around 30 D.U. due to overestimation

at the UTLS region, consistent with similar studies.