Relationship between frontal systems and extreme precipitation over southern South America

The relationship between frontal systems and extreme precipitation events over southern South America is analyzed for the austral winter (May--August) and spring (September-December), on a 39-year period spanning from 1979 to 2017. Daily gridded data from the CPC Global Unified Precipitation dataset...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Solari, Florencia Ilusión, Blázquez, Josefina, Solman, Silvina
Formato: Articulo
Lenguaje:Inglés
Publicado: 2022
Materias:
Geofísica
ERA5
extreme precipitation
fronts
South America
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/160199
Aporte de:
SEDICI (UNLP) de Universidad Nacional de La Plata
id I19-R120-10915-160199
record_format dspace
spelling I19-R120-10915-1601992023-11-15T20:06:24Z http://sedici.unlp.edu.ar/handle/10915/160199 Relationship between frontal systems and extreme precipitation over southern South America Solari, Florencia Ilusión Blázquez, Josefina Solman, Silvina 2022-04-19 2023-11-15T16:39:24Z en Geofísica ERA5 extreme precipitation fronts South America The relationship between frontal systems and extreme precipitation events over southern South America is analyzed for the austral winter (May--August) and spring (September-December), on a 39-year period spanning from 1979 to 2017. Daily gridded data from the CPC Global Unified Precipitation dataset and the ERA5 reanalysis is employed. Fronts are identified by means of an objective front index (FI) that takes into account both dynamic (cyclonic vorticity) and thermodynamic (thermal contrast) characteristics. Extreme precipitation is characterized by the seasonal 95th percentile.Fronts occur in midlatitudes in about 10% of the days but there is a seasonal shift with larger occurrence frequencies located at southern latitudes in spring compared to winter. Front intensity-calculated as the seasonal mean of FI-is stronger in winter than in spring but the spatial pattern is similar on both seasons. Fronts explain about 50% of extreme precipitation on winter and 40% on spring; the percentage of total precipitation explained by fronts is lower but the spatial distribution is similar.Comparison between fronts that produce precipitation and the ones associated with extreme precipitation revealed that the latter are more intense on average. Fronts that produce extreme precipitation have a stronger dynamic forcing (i.e. higher cyclonic vorticity values) and a higher moisture availability (higher specific humidity anomaly). These two characteristics are the most promising for enhancing extreme precipitation events forecast. Facultad de Ciencias Astronómicas y Geofísicas Consejo Nacional de Investigaciones Científicas y Técnicas Articulo Articulo http://creativecommons.org/licenses/by-nc-nd/4.0/ Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) application/pdf 7535-7549
institution Universidad Nacional de La Plata
institution_str I-19
repository_str R-120
collection SEDICI (UNLP)
language Inglés
topic Geofísica
ERA5
extreme precipitation
fronts
South America
spellingShingle Geofísica
ERA5
extreme precipitation
fronts
South America
Solari, Florencia Ilusión
Blázquez, Josefina
Solman, Silvina
Relationship between frontal systems and extreme precipitation over southern South America
topic_facet Geofísica
ERA5
extreme precipitation
fronts
South America
description The relationship between frontal systems and extreme precipitation events over southern South America is analyzed for the austral winter (May--August) and spring (September-December), on a 39-year period spanning from 1979 to 2017. Daily gridded data from the CPC Global Unified Precipitation dataset and the ERA5 reanalysis is employed. Fronts are identified by means of an objective front index (FI) that takes into account both dynamic (cyclonic vorticity) and thermodynamic (thermal contrast) characteristics. Extreme precipitation is characterized by the seasonal 95th percentile.Fronts occur in midlatitudes in about 10% of the days but there is a seasonal shift with larger occurrence frequencies located at southern latitudes in spring compared to winter. Front intensity-calculated as the seasonal mean of FI-is stronger in winter than in spring but the spatial pattern is similar on both seasons. Fronts explain about 50% of extreme precipitation on winter and 40% on spring; the percentage of total precipitation explained by fronts is lower but the spatial distribution is similar.Comparison between fronts that produce precipitation and the ones associated with extreme precipitation revealed that the latter are more intense on average. Fronts that produce extreme precipitation have a stronger dynamic forcing (i.e. higher cyclonic vorticity values) and a higher moisture availability (higher specific humidity anomaly). These two characteristics are the most promising for enhancing extreme precipitation events forecast.
format Articulo
Articulo
author Solari, Florencia Ilusión
Blázquez, Josefina
Solman, Silvina
author_facet Solari, Florencia Ilusión
Blázquez, Josefina
Solman, Silvina
author_sort Solari, Florencia Ilusión
title Relationship between frontal systems and extreme precipitation over southern South America
title_short Relationship between frontal systems and extreme precipitation over southern South America
title_full Relationship between frontal systems and extreme precipitation over southern South America
title_fullStr Relationship between frontal systems and extreme precipitation over southern South America
title_full_unstemmed Relationship between frontal systems and extreme precipitation over southern South America
title_sort relationship between frontal systems and extreme precipitation over southern south america
publishDate 2022
url http://sedici.unlp.edu.ar/handle/10915/160199
work_keys_str_mv AT solariflorenciailusion relationshipbetweenfrontalsystemsandextremeprecipitationoversouthernsouthamerica
AT blazquezjosefina relationshipbetweenfrontalsystemsandextremeprecipitationoversouthernsouthamerica
AT solmansilvina relationshipbetweenfrontalsystemsandextremeprecipitationoversouthernsouthamerica
_version_ 1807221803249041408

Ejemplares similares