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Impact of Resolution on the Representation of Precipitation Variability Associated With the ITCZ
Author(s) -
De Benedetti Marc,
Moore G. W. K.
Publication year - 2017
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1002/2017gl075714
Subject(s) - intertropical convergence zone , climatology , precipitation , decorrelation , upwelling , sea surface temperature , convergence zone , geology , convection , environmental science , atmospheric sciences , meteorology , oceanography , geography , algorithm , computer science
The Intertropical Convergence Zone (ITCZ) is responsible for most of the weather and climate in equatorial regions along with many tropical‐midlatitude interactions. It is therefore important to understand how models represent its structure and variability. Most ITCZ‐associated precipitation is convective, making it unclear how horizontal resolution impacts its representation. To assess this, we introduce a novel technique that involves calculation of the precipitation field's decorrelation length scale (DCLS) using model data sets that share a common lineage with horizontal resolutions from 16 to 160 km. All resolutions captured the ITCZ's mean structure; however, imprints of topography, such as Hawaii and sea surface temperature, including the variability associated with upwelling cold water off the coast of South America, are more clearly represented at higher resolutions. The DCLS analysis indicates that there are changes in the spatial variability of the ITCZ's precipitation that are not reflected in its mean structure, thus confirming its utility as a diagnostic.