Summer precipitation variability over South America on long and short intraseasonal timescales

Gonzalez, P. L. M. ORCID: https://orcid.org/0000-0003-0154-0087 and Vera, C. S. (2014) Summer precipitation variability over South America on long and short intraseasonal timescales. Climate Dynamics, 43 (7). pp. 1993-2007. ISSN 0930-7575 doi: 10.1007/s00382-013-2023-2

Abstract/Summary

A dipole pattern in convection between the South Atlantic convergence zone and the subtropical plains of southeastern South America characterizes summer intraseasonal variability over the region. The dipole pattern presents two main bands of temporal variability, with periods between 10 and 30Â days, and 30 and 90Â days; each influenced by different large-scale dynamical forcings. The dipole activity on the 30--90-day band is related to an eastward traveling wavenumber-1 structure in both OLR and circulation anomalies in the tropics, similar to that associated with the Madden--Julian oscillation. The dipole is also related to a teleconnection pattern extended along the South Pacific between Australia and South America. Conversely, the dipole activity on the 10--30-day band does not seem to be associated with tropical convection anomalies. The corresponding circulation anomalies exhibit, in the extratropics, the structure of Rossby-like wave trains, although their sources are not completely clear.

Item Type	Article
URI	https://reading-clone.eprints-hosting.org/id/eprint/85688
Item Type	Article
Refereed	Yes
Divisions	Science > School of Mathematical, Physical and Computational Sciences > NCAS Science > School of Mathematical, Physical and Computational Sciences > Department of Meteorology
Publisher	Springer
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