气候变化领域集成服务门户(CCPortal): Assessing the skill of all-season diverse Madden–Julian oscillation indices for the intraseasonal Amazon precipitation

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DOI	10.1007/s00382-020-05202-9
	Assessing the skill of all-season diverse Madden–Julian oscillation indices for the intraseasonal Amazon precipitation
	Mayta V.C.; Silva N.P.; Ambrizzi T.; Dias P.L.S.; Espinoza J.C.
发表日期	2020
ISSN	0930-7575
起始页码	3729
结束页码	3749
卷号	54
英文摘要	Madden–Julian Oscillation (MJO) impact on the Amazon intraseasonal precipitation assessed by different MJO indices is investigated through an analysis of composite events and observed case studies. The MJO indices diagnosing skill is described in detail using reanalysis, satellite, and gauge-based gridded rainfall data. Three types of existing MJO indices are considered: (1) OLR-based MJO (OMI index); (2) dynamically- or circulation-based MJO (VPM index); and (3) combined convectively- and dynamically-based MJO (Wheeler–Hendon RMM index). Our results suggest that, in the large-scale (i.e., around the global tropics), even in the regional domain, the MJO OLR-only index well-represent the dynamical and convective features associated with the intraseasonal variability. On the other hand, each index gives diverging results on rainfall characterization over the Amazon Basin (AB). For instance, the cumulative distribution of precipitation for each MJO phase and index depicts considerable differences in the main climatic regions of the AB, indicating a diverging intraseasonal representation for extreme rainfall values. In addition, when event-by-event is assessed, details as well as the identification of events themselves can differ among indices. This characteristic is particularly observed during extreme rainfall events in the AB. A significant percentage of MJO activity is detected only by the MJO OLR-based index. Because the large-scale zonal circulation dominates the dynamically-based indices (RMM and VPM), the MJO impact in these indices is not an appropriate measure of convective MJO activity. Since the convective component of the MJO is our primary objective, the results presented in this study show that the OLR-based MJO index is able to better account for the MJO impacts over the AB. The indices considered in this study are often used for monitoring and forecasting the MJO activity over South America. However, given the dissimilarity of the representation of precipitation in the AB, our findings also support the consideration of a regional index for monitoring and forecasting the MJO impacts. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Amazon Basin; extreme rainfall events; Intraseasonal variability; Madden–Julian oscillation
语种	英语
scopus关键词	atmospheric circulation; atmospheric dynamics; extreme event; Madden-Julian oscillation; precipitation (climatology); rainfall; satellite data; seasonal variation; tropical meteorology; weather forecasting; Amazon River; South America
来源期刊	Climate Dynamics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/145507
作者单位	Departamento de Ciências Atmosféricas, IAG, Universidade de São Paulo, São Paulo, SP, Brazil; Institut des Géosciences de l’Environnement (IGE, UMR 5001), Université Grenoble Alpes, IRD, CNRS, Grenoble INP, Grenoble, France
推荐引用方式 GB/T 7714	Mayta V.C.,Silva N.P.,Ambrizzi T.,等. Assessing the skill of all-season diverse Madden–Julian oscillation indices for the intraseasonal Amazon precipitation[J],2020,54.
APA	Mayta V.C.,Silva N.P.,Ambrizzi T.,Dias P.L.S.,&Espinoza J.C..(2020).Assessing the skill of all-season diverse Madden–Julian oscillation indices for the intraseasonal Amazon precipitation.Climate Dynamics,54.
MLA	Mayta V.C.,et al."Assessing the skill of all-season diverse Madden–Julian oscillation indices for the intraseasonal Amazon precipitation".Climate Dynamics 54(2020).