An empirically derived inorganic sea spray source function incorporating sea surface temperature
We have developed an inorganic sea spray source function that is based upon state-of-the-art measurements of sea spray aerosol production using a temperature-controlled plunging jet sea spray aerosol chamber. The size-resolved particle production was measured between 0.01 and 10 μm dry diameter. Par...
Published in: | Atmospheric Chemistry and Physics |
---|---|
Main Authors: | , , , , , , , |
Format: | Text |
Language: | English |
Published: |
2018
|
Subjects: | |
Online Access: | https://doi.org/10.5194/acp-15-11047-2015 https://www.atmos-chem-phys.net/15/11047/2015/ |
id |
ftcopernicus:oai:publications.copernicus.org:acp30132 |
---|---|
record_format |
openpolar |
spelling |
ftcopernicus:oai:publications.copernicus.org:acp30132 2023-05-15T18:26:02+02:00 An empirically derived inorganic sea spray source function incorporating sea surface temperature Salter, M. E. Zieger, P. Acosta Navarro, J. C. Grythe, H. Kirkevåg, A. Rosati, B. Riipinen, I. Nilsson, E. D. 2018-09-06 application/pdf https://doi.org/10.5194/acp-15-11047-2015 https://www.atmos-chem-phys.net/15/11047/2015/ eng eng doi:10.5194/acp-15-11047-2015 https://www.atmos-chem-phys.net/15/11047/2015/ eISSN: 1680-7324 Text 2018 ftcopernicus https://doi.org/10.5194/acp-15-11047-2015 2019-12-24T09:53:04Z We have developed an inorganic sea spray source function that is based upon state-of-the-art measurements of sea spray aerosol production using a temperature-controlled plunging jet sea spray aerosol chamber. The size-resolved particle production was measured between 0.01 and 10 μm dry diameter. Particle production decreased non-linearly with increasing seawater temperature (between −1 and 30 °C) similar to previous findings. In addition, we observed that the particle effective radius, as well as the particle surface, particle volume and particle mass, increased with increasing seawater temperature due to increased production of particles with dry diameters greater than 1 μm. By combining these measurements with the volume of air entrained by the plunging jet we have determined the size-resolved particle flux as a function of air entrainment. Through the use of existing parameterisations of air entrainment as a function of wind speed, we were subsequently able to scale our laboratory measurements of particle production to wind speed. By scaling in this way we avoid some of the difficulties associated with defining the "white area" of the laboratory whitecap – a contentious issue when relating laboratory measurements of particle production to oceanic whitecaps using the more frequently applied whitecap method. The here-derived inorganic sea spray source function was implemented in a Lagrangian particle dispersion model (FLEXPART – FLEXible PARTicle dispersion model). An estimated annual global flux of inorganic sea spray aerosol of 5.9 ± 0.2 Pg yr −1 was derived that is close to the median of estimates from the same model using a wide range of existing sea spray source functions. When using the source function derived here, the model also showed good skill in predicting measurements of Na + concentration at a number of field sites further underlining the validity of our source function. In a final step, the sensitivity of a large-scale model (NorESM – the Norwegian Earth System Model) to our new source function was tested. Compared to the previously implemented parameterisation, a clear decrease of sea spray aerosol number flux and increase in aerosol residence time was observed, especially over the Southern Ocean. At the same time an increase in aerosol optical depth due to an increase in the number of particles with optically relevant sizes was found. That there were noticeable regional differences may have important implications for aerosol optical properties and number concentrations, subsequently also affecting the indirect radiative forcing by non-sea spray anthropogenic aerosols. Text Southern Ocean Copernicus Publications: E-Journals Southern Ocean Atmospheric Chemistry and Physics 15 19 11047 11066 |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
We have developed an inorganic sea spray source function that is based upon state-of-the-art measurements of sea spray aerosol production using a temperature-controlled plunging jet sea spray aerosol chamber. The size-resolved particle production was measured between 0.01 and 10 μm dry diameter. Particle production decreased non-linearly with increasing seawater temperature (between −1 and 30 °C) similar to previous findings. In addition, we observed that the particle effective radius, as well as the particle surface, particle volume and particle mass, increased with increasing seawater temperature due to increased production of particles with dry diameters greater than 1 μm. By combining these measurements with the volume of air entrained by the plunging jet we have determined the size-resolved particle flux as a function of air entrainment. Through the use of existing parameterisations of air entrainment as a function of wind speed, we were subsequently able to scale our laboratory measurements of particle production to wind speed. By scaling in this way we avoid some of the difficulties associated with defining the "white area" of the laboratory whitecap – a contentious issue when relating laboratory measurements of particle production to oceanic whitecaps using the more frequently applied whitecap method. The here-derived inorganic sea spray source function was implemented in a Lagrangian particle dispersion model (FLEXPART – FLEXible PARTicle dispersion model). An estimated annual global flux of inorganic sea spray aerosol of 5.9 ± 0.2 Pg yr −1 was derived that is close to the median of estimates from the same model using a wide range of existing sea spray source functions. When using the source function derived here, the model also showed good skill in predicting measurements of Na + concentration at a number of field sites further underlining the validity of our source function. In a final step, the sensitivity of a large-scale model (NorESM – the Norwegian Earth System Model) to our new source function was tested. Compared to the previously implemented parameterisation, a clear decrease of sea spray aerosol number flux and increase in aerosol residence time was observed, especially over the Southern Ocean. At the same time an increase in aerosol optical depth due to an increase in the number of particles with optically relevant sizes was found. That there were noticeable regional differences may have important implications for aerosol optical properties and number concentrations, subsequently also affecting the indirect radiative forcing by non-sea spray anthropogenic aerosols. |
format |
Text |
author |
Salter, M. E. Zieger, P. Acosta Navarro, J. C. Grythe, H. Kirkevåg, A. Rosati, B. Riipinen, I. Nilsson, E. D. |
spellingShingle |
Salter, M. E. Zieger, P. Acosta Navarro, J. C. Grythe, H. Kirkevåg, A. Rosati, B. Riipinen, I. Nilsson, E. D. An empirically derived inorganic sea spray source function incorporating sea surface temperature |
author_facet |
Salter, M. E. Zieger, P. Acosta Navarro, J. C. Grythe, H. Kirkevåg, A. Rosati, B. Riipinen, I. Nilsson, E. D. |
author_sort |
Salter, M. E. |
title |
An empirically derived inorganic sea spray source function incorporating sea surface temperature |
title_short |
An empirically derived inorganic sea spray source function incorporating sea surface temperature |
title_full |
An empirically derived inorganic sea spray source function incorporating sea surface temperature |
title_fullStr |
An empirically derived inorganic sea spray source function incorporating sea surface temperature |
title_full_unstemmed |
An empirically derived inorganic sea spray source function incorporating sea surface temperature |
title_sort |
empirically derived inorganic sea spray source function incorporating sea surface temperature |
publishDate |
2018 |
url |
https://doi.org/10.5194/acp-15-11047-2015 https://www.atmos-chem-phys.net/15/11047/2015/ |
geographic |
Southern Ocean |
geographic_facet |
Southern Ocean |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_source |
eISSN: 1680-7324 |
op_relation |
doi:10.5194/acp-15-11047-2015 https://www.atmos-chem-phys.net/15/11047/2015/ |
op_doi |
https://doi.org/10.5194/acp-15-11047-2015 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
15 |
container_issue |
19 |
container_start_page |
11047 |
op_container_end_page |
11066 |
_version_ |
1766207837364551680 |