Large-scale variability modes of freshwater flux and precipitation over the Atlantic
International audience Precipitation (P) and freshwater (E-P) fluxes at the air-sea interface are investigated in the Atlantic Ocean sector using the reanalyses of the European Centre for Medium Range Weather Forecasts (ERA) and of the National Centers for Environmental Prediction (NCEP). A canonica...
Published in: | Climate Dynamics |
---|---|
Main Authors: | , |
Other Authors: | , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2002
|
Subjects: | |
Online Access: | https://hal.science/hal-00772127 https://doi.org/10.1007/S003820100182 |
id |
ftunivnantes:oai:HAL:hal-00772127v1 |
---|---|
record_format |
openpolar |
spelling |
ftunivnantes:oai:HAL:hal-00772127v1 2023-05-15T17:36:24+02:00 Large-scale variability modes of freshwater flux and precipitation over the Atlantic Bojariu, R. Reverdin, Gilles Laboratoire d'océanographie dynamique et de climatologie (LODYC) Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS) 2002 https://hal.science/hal-00772127 https://doi.org/10.1007/S003820100182 en eng HAL CCSD Springer Verlag info:eu-repo/semantics/altIdentifier/doi/10.1007/S003820100182 hal-00772127 https://hal.science/hal-00772127 BIBCODE: 2002ClDy.18.369B doi:10.1007/S003820100182 ISSN: 0930-7575 EISSN: 1432-0894 Climate Dynamics https://hal.science/hal-00772127 Climate Dynamics, 2002, 18, pp.369-381. ⟨10.1007/S003820100182⟩ [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph] [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph] info:eu-repo/semantics/article Journal articles 2002 ftunivnantes https://doi.org/10.1007/S003820100182 2023-01-17T23:43:51Z International audience Precipitation (P) and freshwater (E-P) fluxes at the air-sea interface are investigated in the Atlantic Ocean sector using the reanalyses of the European Centre for Medium Range Weather Forecasts (ERA) and of the National Centers for Environmental Prediction (NCEP). A canonical correlation analysis method between these fields and sea level pressure (SLP) is used to identify patterns. We also test whether precipitation and freshwater fluxes can be reconstructed from SLP data. In the winter months, patterns associated with both the North Atlantic Oscillation (NAO) and the East Atlantic (EA) mode are identified. The signals are strong enough to be reconstructed from the reanalysis fields, and they correspond to a significant part of the variability. The NAO signal is more robust than the EA one. The NAO-related variability mode is also present when the monthly precipitation rate is averaged for the winter season and even for annual averages. However, in the later case, other variability of natural origin (for instance, ENSO variability) or noise from the model and assimilation system prevents the reconstruction of E-P associated with NAO from SLP variability. Difficulties are identified in the tropical Atlantic with a different behaviour of NCEP and ERA precipitation variability, especially near the Inter Tropical Convergence Zone (ITCZ). The ERA patterns suggest a NAO signature in the tropical Atlantic which has clear monthly patterns and indicates a link between the phase of NAO and changes in the position and intensity of ITCZ. However, the analysis of winter rainfall based on satellite and in situ data does not support the monthly tropical pattern of ERA precipitation although it suggests a relation between convection near 15°S and NAO during northern winter. Article in Journal/Newspaper North Atlantic North Atlantic oscillation Université de Nantes: HAL-UNIV-NANTES Climate Dynamics 18 5 369 381 |
institution |
Open Polar |
collection |
Université de Nantes: HAL-UNIV-NANTES |
op_collection_id |
ftunivnantes |
language |
English |
topic |
[PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph] [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph] |
spellingShingle |
[PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph] [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph] Bojariu, R. Reverdin, Gilles Large-scale variability modes of freshwater flux and precipitation over the Atlantic |
topic_facet |
[PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph] [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph] |
description |
International audience Precipitation (P) and freshwater (E-P) fluxes at the air-sea interface are investigated in the Atlantic Ocean sector using the reanalyses of the European Centre for Medium Range Weather Forecasts (ERA) and of the National Centers for Environmental Prediction (NCEP). A canonical correlation analysis method between these fields and sea level pressure (SLP) is used to identify patterns. We also test whether precipitation and freshwater fluxes can be reconstructed from SLP data. In the winter months, patterns associated with both the North Atlantic Oscillation (NAO) and the East Atlantic (EA) mode are identified. The signals are strong enough to be reconstructed from the reanalysis fields, and they correspond to a significant part of the variability. The NAO signal is more robust than the EA one. The NAO-related variability mode is also present when the monthly precipitation rate is averaged for the winter season and even for annual averages. However, in the later case, other variability of natural origin (for instance, ENSO variability) or noise from the model and assimilation system prevents the reconstruction of E-P associated with NAO from SLP variability. Difficulties are identified in the tropical Atlantic with a different behaviour of NCEP and ERA precipitation variability, especially near the Inter Tropical Convergence Zone (ITCZ). The ERA patterns suggest a NAO signature in the tropical Atlantic which has clear monthly patterns and indicates a link between the phase of NAO and changes in the position and intensity of ITCZ. However, the analysis of winter rainfall based on satellite and in situ data does not support the monthly tropical pattern of ERA precipitation although it suggests a relation between convection near 15°S and NAO during northern winter. |
author2 |
Laboratoire d'océanographie dynamique et de climatologie (LODYC) Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS) |
format |
Article in Journal/Newspaper |
author |
Bojariu, R. Reverdin, Gilles |
author_facet |
Bojariu, R. Reverdin, Gilles |
author_sort |
Bojariu, R. |
title |
Large-scale variability modes of freshwater flux and precipitation over the Atlantic |
title_short |
Large-scale variability modes of freshwater flux and precipitation over the Atlantic |
title_full |
Large-scale variability modes of freshwater flux and precipitation over the Atlantic |
title_fullStr |
Large-scale variability modes of freshwater flux and precipitation over the Atlantic |
title_full_unstemmed |
Large-scale variability modes of freshwater flux and precipitation over the Atlantic |
title_sort |
large-scale variability modes of freshwater flux and precipitation over the atlantic |
publisher |
HAL CCSD |
publishDate |
2002 |
url |
https://hal.science/hal-00772127 https://doi.org/10.1007/S003820100182 |
genre |
North Atlantic North Atlantic oscillation |
genre_facet |
North Atlantic North Atlantic oscillation |
op_source |
ISSN: 0930-7575 EISSN: 1432-0894 Climate Dynamics https://hal.science/hal-00772127 Climate Dynamics, 2002, 18, pp.369-381. ⟨10.1007/S003820100182⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1007/S003820100182 hal-00772127 https://hal.science/hal-00772127 BIBCODE: 2002ClDy.18.369B doi:10.1007/S003820100182 |
op_doi |
https://doi.org/10.1007/S003820100182 |
container_title |
Climate Dynamics |
container_volume |
18 |
container_issue |
5 |
container_start_page |
369 |
op_container_end_page |
381 |
_version_ |
1766135871054020608 |