Open AccessDouble intertropical convergence zones over the eastern Pacific Ocean: Contrasting impacts of the eastern Pacific‐ and central Pacific‐type El Niños
Author(s) -
Yan Li,
Li Gen
Publication year - 2018
Publication title -
atmospheric science letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.951
H-Index - 45
ISSN - 1530-261X
DOI - 10.1002/asl.852
Subject(s) - intertropical convergence zone , pacific ocean , oceanography , geology , climatology , sea surface temperature , anomaly (physics) , convergence zone , geography , precipitation , physics , condensed matter physics , meteorology
A double intertropical convergence zone (ITCZ) with poor equatorial rainfall over the eastern Pacific Ocean distinctively occurs in March–April. Here we find that double ITCZs and equatorial precipitation are strongly linked to meridionally symmetric (or asymmetric) sea surface temperature (SST) anomaly patterns during eastern Pacific (EP)‐type (or central Pacific [CP]‐type) El Niño episodes. EP‐type El Niño weakens the north–south asymmetry of the eastern Pacific double ITCZs by moving them equatorward. In contrast, CP‐type El Niño strengthens the north–south asymmetry of the double ITCZs by strengthening the northern ITCZ and weakening the southern ITCZ. While EP‐type El Niño brings unique flourishing Galápagos Islands owing to warm equatorial SST anomalies with major local and remote climate effects, CP‐type El Niño causes drier Galápagos Islands by decreasing equatorial eastern Pacific SST. This study highlights the distinctly different climate effects of EP‐ and CP‐type El Niños in the region.