Optical characteristics of desert dust over the east mediterranean during summer

A case study

D. Balis, V. Amiridis, S. Kazadzis, A. Papayannis, G. Tsaknakis, Stylianos Tzortzakis, N. Kalivitis, M. Vrekoussis, M. Kanakidou, N. Mihalopoulos, G. Chourdakis, S. Nickovic, C. Pérez, J. Baldasano, M. Drakakis

Research output: Contribution to journalArticle

Abstract

High aerosol optical depth (AOD) values, larger than 0.6, are systematically observed in the Ultraviolet (UV) region both by sunphotometers and lidar systems over Greece during summertime. To study in more detail the characteristics and the origin of these high AOD values, a campaign took place in Greece in the frame of the PHOENICS (Particles of Human Origin Extinguishing Natural solar radiation In Climate Systems) and EARLINET (European Aerosol Lidar Network) projects during August-September of 2003, which included simultaneous sunphotometric and lidar measurements at three sites covering the north-south axis of Greece: Thessaloniki, Athens and Finokalia, Crete. Several events with high AOD values have been observed over the measuring sites during the campaign period, many of them corresponding to Saharan dust. In this paper we focused on the event of 30 and 31 August 2003, when a dust layer in the height range of 2000-5000 m, progressively affected all three stations. This layer showed a complex behavior concerning its spatial evolution and allowed us to study the changes in the optical properties of the desert dust particles along their transport due to aging and mixing with other types of aerosol. The extinction-to-backscatter ratio determined on the 30 August 2003 at Thessaloniki was approximately 50 sr, characteristic for rather spherical mineral particles, and the measured color index of 0.4 was within the typical range of values for desert dust. Mixing of the desert dust with other sources of aerosols resulted the next day in over- all smaller and less absorbing population of particles with a lidar ratio of 20 sr. Mixing of polluted air-masses originating from Northern Greece and Crete and Saharan dust result in very high aerosol backscatter values reaching 7Mm-1sr-1 over Finokalia. The Saharan dust observed over Athens followed a different spatial evolution and was not mixed with the boundary layer aerosols mainly originating from local pollution.

Original languageEnglish
Pages (from-to)807-821
Number of pages15
JournalAtmospheric Chemistry and Physics
Volume24
Issue number3
Publication statusPublished - 2006
Externally publishedYes

Fingerprint

desert
aerosol
dust
summer
lidar
optical depth
backscatter
optical property
air mass
solar radiation
boundary layer
extinction
pollution
particle
climate
mineral

Keywords

  • Atmospheric composition and structure (Aerosols and particles
  • Instruments and techniques)
  • Pollution -urban and regional

ASJC Scopus subject areas

  • Atmospheric Science

Cite this

Balis, D., Amiridis, V., Kazadzis, S., Papayannis, A., Tsaknakis, G., Tzortzakis, S., ... Drakakis, M. (2006). Optical characteristics of desert dust over the east mediterranean during summer: A case study. Atmospheric Chemistry and Physics, 24(3), 807-821.

Optical characteristics of desert dust over the east mediterranean during summer : A case study. / Balis, D.; Amiridis, V.; Kazadzis, S.; Papayannis, A.; Tsaknakis, G.; Tzortzakis, Stylianos; Kalivitis, N.; Vrekoussis, M.; Kanakidou, M.; Mihalopoulos, N.; Chourdakis, G.; Nickovic, S.; Pérez, C.; Baldasano, J.; Drakakis, M.

In: Atmospheric Chemistry and Physics, Vol. 24, No. 3, 2006, p. 807-821.

Research output: Contribution to journalArticle

Balis, D, Amiridis, V, Kazadzis, S, Papayannis, A, Tsaknakis, G, Tzortzakis, S, Kalivitis, N, Vrekoussis, M, Kanakidou, M, Mihalopoulos, N, Chourdakis, G, Nickovic, S, Pérez, C, Baldasano, J & Drakakis, M 2006, 'Optical characteristics of desert dust over the east mediterranean during summer: A case study', Atmospheric Chemistry and Physics, vol. 24, no. 3, pp. 807-821.
Balis, D. ; Amiridis, V. ; Kazadzis, S. ; Papayannis, A. ; Tsaknakis, G. ; Tzortzakis, Stylianos ; Kalivitis, N. ; Vrekoussis, M. ; Kanakidou, M. ; Mihalopoulos, N. ; Chourdakis, G. ; Nickovic, S. ; Pérez, C. ; Baldasano, J. ; Drakakis, M. / Optical characteristics of desert dust over the east mediterranean during summer : A case study. In: Atmospheric Chemistry and Physics. 2006 ; Vol. 24, No. 3. pp. 807-821.
@article{72e3b31bae35412e948d2365837a4f14,
title = "Optical characteristics of desert dust over the east mediterranean during summer: A case study",
abstract = "High aerosol optical depth (AOD) values, larger than 0.6, are systematically observed in the Ultraviolet (UV) region both by sunphotometers and lidar systems over Greece during summertime. To study in more detail the characteristics and the origin of these high AOD values, a campaign took place in Greece in the frame of the PHOENICS (Particles of Human Origin Extinguishing Natural solar radiation In Climate Systems) and EARLINET (European Aerosol Lidar Network) projects during August-September of 2003, which included simultaneous sunphotometric and lidar measurements at three sites covering the north-south axis of Greece: Thessaloniki, Athens and Finokalia, Crete. Several events with high AOD values have been observed over the measuring sites during the campaign period, many of them corresponding to Saharan dust. In this paper we focused on the event of 30 and 31 August 2003, when a dust layer in the height range of 2000-5000 m, progressively affected all three stations. This layer showed a complex behavior concerning its spatial evolution and allowed us to study the changes in the optical properties of the desert dust particles along their transport due to aging and mixing with other types of aerosol. The extinction-to-backscatter ratio determined on the 30 August 2003 at Thessaloniki was approximately 50 sr, characteristic for rather spherical mineral particles, and the measured color index of 0.4 was within the typical range of values for desert dust. Mixing of the desert dust with other sources of aerosols resulted the next day in over- all smaller and less absorbing population of particles with a lidar ratio of 20 sr. Mixing of polluted air-masses originating from Northern Greece and Crete and Saharan dust result in very high aerosol backscatter values reaching 7Mm-1sr-1 over Finokalia. The Saharan dust observed over Athens followed a different spatial evolution and was not mixed with the boundary layer aerosols mainly originating from local pollution.",
keywords = "Atmospheric composition and structure (Aerosols and particles, Instruments and techniques), Pollution -urban and regional",
author = "D. Balis and V. Amiridis and S. Kazadzis and A. Papayannis and G. Tsaknakis and Stylianos Tzortzakis and N. Kalivitis and M. Vrekoussis and M. Kanakidou and N. Mihalopoulos and G. Chourdakis and S. Nickovic and C. P{\'e}rez and J. Baldasano and M. Drakakis",
year = "2006",
language = "English",
volume = "24",
pages = "807--821",
journal = "Atmospheric Chemistry and Physics",
issn = "1680-7316",
publisher = "European Geosciences Union",
number = "3",

}

TY - JOUR

T1 - Optical characteristics of desert dust over the east mediterranean during summer

T2 - A case study

AU - Balis, D.

AU - Amiridis, V.

AU - Kazadzis, S.

AU - Papayannis, A.

AU - Tsaknakis, G.

AU - Tzortzakis, Stylianos

AU - Kalivitis, N.

AU - Vrekoussis, M.

AU - Kanakidou, M.

AU - Mihalopoulos, N.

AU - Chourdakis, G.

AU - Nickovic, S.

AU - Pérez, C.

AU - Baldasano, J.

AU - Drakakis, M.

PY - 2006

Y1 - 2006

N2 - High aerosol optical depth (AOD) values, larger than 0.6, are systematically observed in the Ultraviolet (UV) region both by sunphotometers and lidar systems over Greece during summertime. To study in more detail the characteristics and the origin of these high AOD values, a campaign took place in Greece in the frame of the PHOENICS (Particles of Human Origin Extinguishing Natural solar radiation In Climate Systems) and EARLINET (European Aerosol Lidar Network) projects during August-September of 2003, which included simultaneous sunphotometric and lidar measurements at three sites covering the north-south axis of Greece: Thessaloniki, Athens and Finokalia, Crete. Several events with high AOD values have been observed over the measuring sites during the campaign period, many of them corresponding to Saharan dust. In this paper we focused on the event of 30 and 31 August 2003, when a dust layer in the height range of 2000-5000 m, progressively affected all three stations. This layer showed a complex behavior concerning its spatial evolution and allowed us to study the changes in the optical properties of the desert dust particles along their transport due to aging and mixing with other types of aerosol. The extinction-to-backscatter ratio determined on the 30 August 2003 at Thessaloniki was approximately 50 sr, characteristic for rather spherical mineral particles, and the measured color index of 0.4 was within the typical range of values for desert dust. Mixing of the desert dust with other sources of aerosols resulted the next day in over- all smaller and less absorbing population of particles with a lidar ratio of 20 sr. Mixing of polluted air-masses originating from Northern Greece and Crete and Saharan dust result in very high aerosol backscatter values reaching 7Mm-1sr-1 over Finokalia. The Saharan dust observed over Athens followed a different spatial evolution and was not mixed with the boundary layer aerosols mainly originating from local pollution.

AB - High aerosol optical depth (AOD) values, larger than 0.6, are systematically observed in the Ultraviolet (UV) region both by sunphotometers and lidar systems over Greece during summertime. To study in more detail the characteristics and the origin of these high AOD values, a campaign took place in Greece in the frame of the PHOENICS (Particles of Human Origin Extinguishing Natural solar radiation In Climate Systems) and EARLINET (European Aerosol Lidar Network) projects during August-September of 2003, which included simultaneous sunphotometric and lidar measurements at three sites covering the north-south axis of Greece: Thessaloniki, Athens and Finokalia, Crete. Several events with high AOD values have been observed over the measuring sites during the campaign period, many of them corresponding to Saharan dust. In this paper we focused on the event of 30 and 31 August 2003, when a dust layer in the height range of 2000-5000 m, progressively affected all three stations. This layer showed a complex behavior concerning its spatial evolution and allowed us to study the changes in the optical properties of the desert dust particles along their transport due to aging and mixing with other types of aerosol. The extinction-to-backscatter ratio determined on the 30 August 2003 at Thessaloniki was approximately 50 sr, characteristic for rather spherical mineral particles, and the measured color index of 0.4 was within the typical range of values for desert dust. Mixing of the desert dust with other sources of aerosols resulted the next day in over- all smaller and less absorbing population of particles with a lidar ratio of 20 sr. Mixing of polluted air-masses originating from Northern Greece and Crete and Saharan dust result in very high aerosol backscatter values reaching 7Mm-1sr-1 over Finokalia. The Saharan dust observed over Athens followed a different spatial evolution and was not mixed with the boundary layer aerosols mainly originating from local pollution.

KW - Atmospheric composition and structure (Aerosols and particles

KW - Instruments and techniques)

KW - Pollution -urban and regional

UR - http://www.scopus.com/inward/record.url?scp=84994000711&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84994000711&partnerID=8YFLogxK

M3 - Article

VL - 24

SP - 807

EP - 821

JO - Atmospheric Chemistry and Physics

JF - Atmospheric Chemistry and Physics

SN - 1680-7316

IS - 3

ER -