| 1. Identity statement | ||||
| Reference Type | Conference Paper (Conference Proceedings) | |||
| Site | mtc-m16b.sid.inpe.br | |||
| Holder Code | isadg {BR SPINPE} ibi 8JMKD3MGPCW/3DT298S | |||
| Repository | cptec.inpe.br/adm_conf/2005/10.31.22.33 | |||
| Last Update | 2006:04.15.18.16.42 (UTC) administrator | |||
| Metadata Repository | cptec.inpe.br/adm_conf/2005/10.31.22.33.36 | |||
| Metadata Last Update | 2018:06.05.03.43.03 (UTC) administrator | |||
| Citation Key | GrimmTede:2006:MeInEl | |||
| Title | Mechanisms of the influence of El Niño and La Niña episodes on the frequency of extreme precipitation events in Brazil  | |||
| Format | CD-ROM, On-line. | |||
| Year | 2006 | |||
| Access Date | 2024, Apr. 25 | |||
| Secondary Type | PRE CI | |||
| Number of Files | 1 | |||
| Size | 561 KiB | |||
| 2. Context | ||||
| Author | 1 Grimm, Alice Marlene 2 Tedeschi, Renata Gonçalves | |||
| Affiliation | 1 Universidade Federal do Paraná, Departamento de Física 2 Caixa Postal 19044. 81531-990 Curitiba, PR, Brazil (Grimm 3 Tedeschi) | |||
| Author e-Mail Address | 1 grimm@fisica.ufpr.br 2 rgtedeschi@pop.com.br | |||
| Editor | Vera, Carolina Nobre, Carlos | |||
| e-Mail Address | grimm@fisica.ufpr.br | |||
| Conference Name | International Conference on Southern Hemisphere Meteorology and Oceanography, 8 (ICSHMO). | |||
| Conference Location | Foz do Iguaçu | |||
| Date | 24-28 Apr. 2006 | |||
| Publisher | American Meteorological Society (AMS) | |||
| Publisher City | 45 Beacon Hill Road, Boston, MA, USA | |||
| Pages | 765-773 | |||
| Book Title | Proceedings | |||
| Tertiary Type | Poster | |||
| Organization | American Meteorological Society (AMS) | |||
| History (UTC) | 2005-10-31 22:33:36 :: grimm@fisica.ufpr.br -> adm_conf :: 2005-12-15 15:36:43 :: adm_conf -> grimm@fisica.ufpr.br :: 2006-03-30 00:21:24 :: grimm@fisica.ufpr.br -> administrator :: 2006-04-18 21:18:11 :: administrator -> lise@dpi.inpe.br :: 2010-12-28 12:36:48 :: lise@dpi.inpe.br -> administrator :: 2010-12-29 15:58:53 :: administrator -> lise@dpi.inpe.br :: 2006 2010-12-29 16:06:13 :: lise@dpi.inpe.br -> administrator :: 2006 2010-12-29 18:54:37 :: administrator -> banon :: 2006 2011-01-02 17:15:13 :: banon -> administrator :: 2006 2018-06-05 03:43:03 :: administrator -> :: 2006 | |||
| 3. Content and structure | ||||
| Is the master or a copy? | is the master | |||
| Content Stage | completed | |||
| Transferable | 1 | |||
| Keywords | Extreme events precipitation El Niño La Niña Brazil | |||
| Abstract | This paper examines how El Niño (EN) e La Niña (LN) episodes modify the frequency of extreme precipitation events in Brazil, and the reason for this modification. Gamma distributions were fit to precipitation in each day of the year, in the period 1956-2002, provided by stations all over Brazil. Daily precipitation data are then replaced by their respective percentiles. Extreme events are those with a three-day average percentile above 85. The number of extreme events was computed for each month of each year. Years were classified as EN, LN and normal years, considering, according to the EN/LN cycle, that the year starts in August (year 0) and ends in July (year +1). The mean frequency of extreme events for each month, within each category of year, and the difference between these mean frequencies for EN and normal years, and for LN and normal years show that EN and LN episodes influence significantly the frequency of extreme events in several regions in Brazil during certain periods. The relationships between large-scale atmospheric perturbations and variations in the frequency of extreme precipitation events are sought through composites of anomalous atmospheric fields during extreme events in EN and LN episodes, in three regions in which there is significant change in the frequency of these events. The general features of those anomalous fields are similar, no matter if the extreme events happen during EN or LN episodes or in normal years. They show the essential ingredients for much precipitation: moisture convergence and mechanisms for lifting the air to the condensation level. To understand why the frequency of extreme events varies significantly between EN and LN episodes, we also formed composites of monthly atmospheric anomalous fields during those episodes. In the regions where the frequency of extreme events increases (decreases) the anomaly composites during extreme events show similarity (difference) with respect to the mean anomalies during EN or LN episodes. This indicates that the frequency of extreme events increases (decreases) when the large-scale perturbations favor (hamper) the circulation anomalies associated with them in those regions. This also means that the behavior of the frequency of extreme events is consistent with that of the monthly or seasonal total precipitation. The same conclusion can be reached through the correlation of sea surface temperature (SST) with the monthly precipitation series or the frequency of extreme events for two regions in which these events had their frequency changed during EN and LN episodes. This correlation analysis was carried out to verify whether there is another mechanism responsible for extreme events that does not work during other rainfall events. In general, the relationship between SST and monthly rainfall is similar to the relationship between SST and the frequency of extreme events. There are, however, some differences. For instance, in southern Brazil the frequency of extreme events is correlated both with SST anomalies in the Pacific Ocean (associated with EN/LN) and in the Atlantic Ocean, while the monthly rainfall is more strongly correlated with SST in the Pacific Ocean.. | |||
| Area | MET | |||
| Type | Hydrological variability and modeling | |||
| doc Directory Content | access | |||
| source Directory Content |
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| agreement Directory Content | there are no files | |||
| 4. Conditions of access and use | ||||
| data URL | http://urlib.net/ibi/cptec.inpe.br/adm_conf/2005/10.31.22.33 | |||
| zipped data URL | http://urlib.net/zip/cptec.inpe.br/adm_conf/2005/10.31.22.33 | |||
| Language | en | |||
| Target File | 765-774.pdf | |||
| User Group | grimm@fisica.ufpr.br administrator | |||
| Visibility | shown | |||
| 5. Allied materials | ||||
| Host Collection | cptec.inpe.br/nobre/2005/06.02.21.14 cptec.inpe.br/walmeida/2003/04.25.17.12 | |||
| 6. Notes | ||||
| Mark | 1 | |||
| Empty Fields | archivingpolicy archivist callnumber contenttype copyholder copyright creatorhistory descriptionlevel dissemination documentstage doi edition group identifier isbn issn label lineage mirrorrepository nextedition nexthigherunit notes numberofvolumes orcid parameterlist parentrepositories previousedition previouslowerunit progress project readergroup readpermission resumeid rightsholder schedulinginformation secondarydate secondarykey secondarymark serieseditor session shorttitle sponsor subject tertiarymark url versiontype volume | |||