The pulsating nature of large-scale Saharan dust transport as a result of interplays between mid-latitude Rossby waves and the North African Dipole Intensity
It was previously shown that during August the export of Saharan dust to the Atlantic was strongly affected by the difference of the 700-hPa geopotential height anomaly between the subtropics and the tropics over North Africa, which was termed the North African Dipole Intensity (NAFDI). In this work...
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ftupcatalunyair:oai:upcommons.upc.edu:2117/108640 2024-09-09T19:56:59+00:00 The pulsating nature of large-scale Saharan dust transport as a result of interplays between mid-latitude Rossby waves and the North African Dipole Intensity Cuevas, E. Gómez-Peláez, A.J. Rodríguez, S. Terradellas, E. Basart, S. García, R.D. García, O.E. Alonso-Pérez, S. Barcelona Supercomputing Center 2017-10 17 p. application/pdf http://hdl.handle.net/2117/108640 https://doi.org/10.1016/j.atmosenv.2017.08.059 eng eng Elsevier http://www.sciencedirect.com/science/article/pii/S1352231017305757 info:eu-repo/grantAgreement/MINECO/1PE/CGL2015-17-66229-P info:eu-repo/grantAgreement/MINECO/1PE/CGL2013-46736 Cuevas, E. [et al.]. The pulsating nature of large-scale Saharan dust transport as a result of interplays between mid-latitude Rossby waves and the North African Dipole Intensity. "Atmospheric Environment", Octubre 2017, vol. 167, p. 586-602. 1352-2310 http://hdl.handle.net/2117/108640 doi:10.1016/j.atmosenv.2017.08.059 Attribution-NonCommercial-NoDerivs 4.0 Spain http://creativecommons.org/licenses/by-nc-nd/4.0/es/ Open Access Àrees temàtiques de la UPC::Energies Dust--adverse effects Sahara--Climate Saharan dust North African Dipole Intensity (NAFDI) Saharan Heat Low (SHL) Deserts--Àfrica del Nord Sàhara Article 2017 ftupcatalunyair https://doi.org/10.1016/j.atmosenv.2017.08.059 2024-07-25T11:12:57Z It was previously shown that during August the export of Saharan dust to the Atlantic was strongly affected by the difference of the 700-hPa geopotential height anomaly between the subtropics and the tropics over North Africa, which was termed the North African Dipole Intensity (NAFDI). In this work a more comprehensive analysis of the NAFDI is performed, focusing on the entire summer dust season (June–September), and examining the interactions between the mid-latitude Rossby waves (MLRWs) and NAFDI. Widespread and notable aerosol optical depth (AOD) monthly anomalies are found for each NAFDI-phase over the dust corridors off the Sahara, indicating that NAFDI presents intra-seasonal variability and drives dust transport over both the Mediterranean basin and the North Atlantic. Those summer months with the same NAFDI-phase show similar AOD-anomaly patterns. Variations in NAFDI-phase also control the displacement of the Saharan Heat Low (SHL) westwards or eastwards through horizontal advection of temperature over Morocco-Western Sahara or eastern Algeria-Western Libya, respectively. The connection between the SHL and the NAFDI is quantified statistically by introducing two new daily indexes that account for their respective phases (NAFDI daily index -NAFDIDI-, and SHL longitudinal shift index -SHLLSI-) and explained physically using the energy equation of the atmospheric dynamics. The Pearson's correlation coefficient between the one–day-lag SHLLSI and the NAFDIDI for an extended summer season (1980–2013) is 0.78. A positive NAFDI is associated with the West-phase of the SHL, dust sources intensification on central Algeria, and positive AOD anomalies over this region and the Subtropical North Atlantic. A negative NAFDI is associated with the East-phase of the SHL, and positive AOD anomalies over central-eastern Sahara and the central-western Mediterranean Sea. The results point out that the phase changes of NAFDI at intra-seasonal time scale are conducted by those MLRWs that penetrate deeply into the low ... Article in Journal/Newspaper North Atlantic Universitat Politècnica de Catalunya, BarcelonaTech: UPCommons - Global access to UPC knowledge Atmospheric Environment 167 586 602 |
institution |
Open Polar |
collection |
Universitat Politècnica de Catalunya, BarcelonaTech: UPCommons - Global access to UPC knowledge |
op_collection_id |
ftupcatalunyair |
language |
English |
topic |
Àrees temàtiques de la UPC::Energies Dust--adverse effects Sahara--Climate Saharan dust North African Dipole Intensity (NAFDI) Saharan Heat Low (SHL) Deserts--Àfrica del Nord Sàhara |
spellingShingle |
Àrees temàtiques de la UPC::Energies Dust--adverse effects Sahara--Climate Saharan dust North African Dipole Intensity (NAFDI) Saharan Heat Low (SHL) Deserts--Àfrica del Nord Sàhara Cuevas, E. Gómez-Peláez, A.J. Rodríguez, S. Terradellas, E. Basart, S. García, R.D. García, O.E. Alonso-Pérez, S. The pulsating nature of large-scale Saharan dust transport as a result of interplays between mid-latitude Rossby waves and the North African Dipole Intensity |
topic_facet |
Àrees temàtiques de la UPC::Energies Dust--adverse effects Sahara--Climate Saharan dust North African Dipole Intensity (NAFDI) Saharan Heat Low (SHL) Deserts--Àfrica del Nord Sàhara |
description |
It was previously shown that during August the export of Saharan dust to the Atlantic was strongly affected by the difference of the 700-hPa geopotential height anomaly between the subtropics and the tropics over North Africa, which was termed the North African Dipole Intensity (NAFDI). In this work a more comprehensive analysis of the NAFDI is performed, focusing on the entire summer dust season (June–September), and examining the interactions between the mid-latitude Rossby waves (MLRWs) and NAFDI. Widespread and notable aerosol optical depth (AOD) monthly anomalies are found for each NAFDI-phase over the dust corridors off the Sahara, indicating that NAFDI presents intra-seasonal variability and drives dust transport over both the Mediterranean basin and the North Atlantic. Those summer months with the same NAFDI-phase show similar AOD-anomaly patterns. Variations in NAFDI-phase also control the displacement of the Saharan Heat Low (SHL) westwards or eastwards through horizontal advection of temperature over Morocco-Western Sahara or eastern Algeria-Western Libya, respectively. The connection between the SHL and the NAFDI is quantified statistically by introducing two new daily indexes that account for their respective phases (NAFDI daily index -NAFDIDI-, and SHL longitudinal shift index -SHLLSI-) and explained physically using the energy equation of the atmospheric dynamics. The Pearson's correlation coefficient between the one–day-lag SHLLSI and the NAFDIDI for an extended summer season (1980–2013) is 0.78. A positive NAFDI is associated with the West-phase of the SHL, dust sources intensification on central Algeria, and positive AOD anomalies over this region and the Subtropical North Atlantic. A negative NAFDI is associated with the East-phase of the SHL, and positive AOD anomalies over central-eastern Sahara and the central-western Mediterranean Sea. The results point out that the phase changes of NAFDI at intra-seasonal time scale are conducted by those MLRWs that penetrate deeply into the low ... |
author2 |
Barcelona Supercomputing Center |
format |
Article in Journal/Newspaper |
author |
Cuevas, E. Gómez-Peláez, A.J. Rodríguez, S. Terradellas, E. Basart, S. García, R.D. García, O.E. Alonso-Pérez, S. |
author_facet |
Cuevas, E. Gómez-Peláez, A.J. Rodríguez, S. Terradellas, E. Basart, S. García, R.D. García, O.E. Alonso-Pérez, S. |
author_sort |
Cuevas, E. |
title |
The pulsating nature of large-scale Saharan dust transport as a result of interplays between mid-latitude Rossby waves and the North African Dipole Intensity |
title_short |
The pulsating nature of large-scale Saharan dust transport as a result of interplays between mid-latitude Rossby waves and the North African Dipole Intensity |
title_full |
The pulsating nature of large-scale Saharan dust transport as a result of interplays between mid-latitude Rossby waves and the North African Dipole Intensity |
title_fullStr |
The pulsating nature of large-scale Saharan dust transport as a result of interplays between mid-latitude Rossby waves and the North African Dipole Intensity |
title_full_unstemmed |
The pulsating nature of large-scale Saharan dust transport as a result of interplays between mid-latitude Rossby waves and the North African Dipole Intensity |
title_sort |
pulsating nature of large-scale saharan dust transport as a result of interplays between mid-latitude rossby waves and the north african dipole intensity |
publisher |
Elsevier |
publishDate |
2017 |
url |
http://hdl.handle.net/2117/108640 https://doi.org/10.1016/j.atmosenv.2017.08.059 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
http://www.sciencedirect.com/science/article/pii/S1352231017305757 info:eu-repo/grantAgreement/MINECO/1PE/CGL2015-17-66229-P info:eu-repo/grantAgreement/MINECO/1PE/CGL2013-46736 Cuevas, E. [et al.]. The pulsating nature of large-scale Saharan dust transport as a result of interplays between mid-latitude Rossby waves and the North African Dipole Intensity. "Atmospheric Environment", Octubre 2017, vol. 167, p. 586-602. 1352-2310 http://hdl.handle.net/2117/108640 doi:10.1016/j.atmosenv.2017.08.059 |
op_rights |
Attribution-NonCommercial-NoDerivs 4.0 Spain http://creativecommons.org/licenses/by-nc-nd/4.0/es/ Open Access |
op_doi |
https://doi.org/10.1016/j.atmosenv.2017.08.059 |
container_title |
Atmospheric Environment |
container_volume |
167 |
container_start_page |
586 |
op_container_end_page |
602 |
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1809927858938707968 |