Mechanisms of tropical precipitation biases in climate models

We investigate the possible causes for inter-model spread in tropical zonal-mean precipitation pattern, which is divided into hemispherically symmetric and anti-symmetric modes via empirical orthogonal function analysis. The symmetric pattern characterizes the leading mode and is tightly related to...

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Detalles Bibliográficos
Autores: Kim, Hanjun, Kang, Sarah M., Takahashi, Ken, Donohoe, Aaron, Pendergrass, Angeline G.
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2020
País:Perú
Institución:Servicio Nacional de Meteorología e Hidrología del Perú
Repositorio:SENAMHI-Institucional
Idioma:inglés
OAI Identifier:oai:repositorio.senamhi.gob.pe:20.500.12542/481
Acceso en línea:https://hdl.handle.net/20.500.12542/481
https://doi.org/10.1007/s00382-020-05325-z
Access Level:acceso abierto
Palabra clave:Tropical Precipitation
Model Uncertainty
Double ITCZ Problem
Modelos
Zona Tropical
Energy Flow
Precipitación
Climatología
http://purl.org/pe-repo/ocde/ford#1.05.00
precipitacion - Clima y Eventos Naturales
Descripción
Sumario:We investigate the possible causes for inter-model spread in tropical zonal-mean precipitation pattern, which is divided into hemispherically symmetric and anti-symmetric modes via empirical orthogonal function analysis. The symmetric pattern characterizes the leading mode and is tightly related to the seasonal amplitude of maximum precipitation position. The energetic constraints link the symmetric pattern to the seasonal amplitude in cross-equatorial atmospheric energy transport AET0 and the annual-mean equatorial net energy input NEI0. Decomposition of AET0 into the energetics variables indicates that the inter-model spread in symmetric precipitation pattern is correlated with the inter-model spread in clear-sky atmospheric shortwave absorption, which most likely arises due to differences in radiative transfer parameterizations rather than water vapor patterns. Among the components that consist NEI0, the inter-model spread in symmetric precipitation pattern is mostly associated with the inter-model spread in net surface energy flux in the equatorial region, which is modulated by the strength of cooling by equatorial upwelling. Our results provide clues to understand the mechanism of tropical precipitation bias, thereby providing guidance for model improvements.