Seasonal variability of aerosol concentration and size distribution in Cape Verde using a continuous aerosol optical spectrometer
One year of, almost continuous, measurements of aerosol optical properties and chemical composition were performed at the outskirts of Praia, Santiago Island, Cape Verde, within the framework of CV-DUST (Atmospheric aerosol in Cape Verde region: seasonal evaluation of composition, sources and transp...
| Main Authors: | , , , , , , , , |
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2014-05-01
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| Series: | Frontiers in Environmental Science |
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| Online Access: | http://journal.frontiersin.org/Journal/10.3389/fenvs.2014.00015/full |
| _version_ | 1828437532194373632 |
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| author | Casimiro Adrião Pio João eCardoso Mário Azevedo Cerqueira Ana eCalvo Teresa Vieira Nunes Célia Anjos Alves Danilo eCustodio Susana Marta Almeida Marina Almeida Silva |
| author_facet | Casimiro Adrião Pio João eCardoso Mário Azevedo Cerqueira Ana eCalvo Teresa Vieira Nunes Célia Anjos Alves Danilo eCustodio Susana Marta Almeida Marina Almeida Silva |
| author_sort | Casimiro Adrião Pio |
| collection | DOAJ |
| description | One year of, almost continuous, measurements of aerosol optical properties and chemical composition were performed at the outskirts of Praia, Santiago Island, Cape Verde, within the framework of CV-DUST (Atmospheric aerosol in Cape Verde region: seasonal evaluation of composition, sources and transport) research project, during 2011. This article reports the aerosol number and mass concentration measurements using a GRIMM Optical Aerosol Spectrometer that provides number size discrimination into 31 size ranges from 0.25 to 32 µm. Time series of 5 min average PM10 concentrations revealed peak values higher than 1000 µg.m-3 during winter dust storm events originating over Northern Africa. The 24 hours average concentrations exceeded the World Health Organization (WHO) guidelines for PM2.5 and PM10 in 20% and 30% of the 2001 days, respectively. Annual average mass concentrations (±standard deviation) for PM1, PM2.5 and PM10 were 5±5, 19±21 and 48±64 µg.m-3, respectively. The annual PM2.5 and PM10 values were also above the limits prescribed by the WHO (10 and 20 µg.m-3, respectively). The aerosol mass size distribution revealed two main modes for particles smaller than 10 µm: a fine mode (0.7-0.8 µm), which possibly results of gas to particle conversion processes; and a coarse mode with maxima at 3-4 µm, which is associated with desert dust and sea salt sources. Within the coarse mode two sub-modes with maxima at 5-6 µm and 10-12 µm were frequently present. |
| first_indexed | 2024-12-10T19:46:50Z |
| format | Article |
| id | doaj.art-6d57f98d4dc44d1f96e8a27cb52afb0c |
| institution | Directory Open Access Journal |
| issn | 2296-665X |
| language | English |
| last_indexed | 2024-12-10T19:46:50Z |
| publishDate | 2014-05-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Environmental Science |
| spelling | doaj.art-6d57f98d4dc44d1f96e8a27cb52afb0c2022-12-22T01:35:51ZengFrontiers Media S.A.Frontiers in Environmental Science2296-665X2014-05-01210.3389/fenvs.2014.0001582423Seasonal variability of aerosol concentration and size distribution in Cape Verde using a continuous aerosol optical spectrometerCasimiro Adrião Pio0João eCardoso1Mário Azevedo Cerqueira2Ana eCalvo3Teresa Vieira Nunes4Célia Anjos Alves5Danilo eCustodio6Susana Marta Almeida7Marina Almeida Silva8Universidade de AveiroUniversidade de Cabo VerdeUniversidade de AveiroUniversidade de AveiroUniversidade de AveiroUniversidade de AveiroUniversidade de AveiroUniversidade de LisboaUniversidade de LisboaOne year of, almost continuous, measurements of aerosol optical properties and chemical composition were performed at the outskirts of Praia, Santiago Island, Cape Verde, within the framework of CV-DUST (Atmospheric aerosol in Cape Verde region: seasonal evaluation of composition, sources and transport) research project, during 2011. This article reports the aerosol number and mass concentration measurements using a GRIMM Optical Aerosol Spectrometer that provides number size discrimination into 31 size ranges from 0.25 to 32 µm. Time series of 5 min average PM10 concentrations revealed peak values higher than 1000 µg.m-3 during winter dust storm events originating over Northern Africa. The 24 hours average concentrations exceeded the World Health Organization (WHO) guidelines for PM2.5 and PM10 in 20% and 30% of the 2001 days, respectively. Annual average mass concentrations (±standard deviation) for PM1, PM2.5 and PM10 were 5±5, 19±21 and 48±64 µg.m-3, respectively. The annual PM2.5 and PM10 values were also above the limits prescribed by the WHO (10 and 20 µg.m-3, respectively). The aerosol mass size distribution revealed two main modes for particles smaller than 10 µm: a fine mode (0.7-0.8 µm), which possibly results of gas to particle conversion processes; and a coarse mode with maxima at 3-4 µm, which is associated with desert dust and sea salt sources. Within the coarse mode two sub-modes with maxima at 5-6 µm and 10-12 µm were frequently present.http://journal.frontiersin.org/Journal/10.3389/fenvs.2014.00015/fullCape VerdeSeasonal variationsize distributionSahara dustPM levels |
| spellingShingle | Casimiro Adrião Pio João eCardoso Mário Azevedo Cerqueira Ana eCalvo Teresa Vieira Nunes Célia Anjos Alves Danilo eCustodio Susana Marta Almeida Marina Almeida Silva Seasonal variability of aerosol concentration and size distribution in Cape Verde using a continuous aerosol optical spectrometer Frontiers in Environmental Science Cape Verde Seasonal variation size distribution Sahara dust PM levels |
| title | Seasonal variability of aerosol concentration and size distribution in Cape Verde using a continuous aerosol optical spectrometer |
| title_full | Seasonal variability of aerosol concentration and size distribution in Cape Verde using a continuous aerosol optical spectrometer |
| title_fullStr | Seasonal variability of aerosol concentration and size distribution in Cape Verde using a continuous aerosol optical spectrometer |
| title_full_unstemmed | Seasonal variability of aerosol concentration and size distribution in Cape Verde using a continuous aerosol optical spectrometer |
| title_short | Seasonal variability of aerosol concentration and size distribution in Cape Verde using a continuous aerosol optical spectrometer |
| title_sort | seasonal variability of aerosol concentration and size distribution in cape verde using a continuous aerosol optical spectrometer |
| topic | Cape Verde Seasonal variation size distribution Sahara dust PM levels |
| url | http://journal.frontiersin.org/Journal/10.3389/fenvs.2014.00015/full |
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