chapter - Atmospheric and Oceanic Science

Similar to LN rainfall composites for the WPDO regime, the corresponding
composites for the CPDO regime show well organized and robust structures in SSA
during the period from October (0) to February (+) (Fig. 14.4). Nevertheless, in this
case, significant negative rainfall anomalies are located slightly to the South of
those for the previous analysis. Negative rainfall anomalies for CPDO regime occupy
most of the study domain by October (0) . These anomalies intensify yielding significant
values extending over southern Brazil, Uruguay, Paraguay, southern
Bolivia and eastern Argentina in November (0) . The negative anomalies remain relatively
strong and occupy most of SSA South of 25°S by December (0) . The negative
anomalies weaken and are limited to western central Argentina in January (+) . At this
time, significant rainfall anomalies are noted in southern Peru (positive) and in eastern
Brazil (negative). Significant anomalies are found in the eastern central
Argentina (positive) and in a small area in central Chile (negative) in February (+) .
Significant positive rainfall anomalies are noted only in a small area of the western
central Brazil in March (+) . Significant negative rainfall anomalies are established in
the southern Uruguay and in the eastern central Argentina in April (+) . LN-related
rainfall anomaly patterns for the CPDO regime present quite small magnitude
anomalies for the remaining subsequent months.
Fig. 14.4. As Fig. 14.3, except for CPDO regime.
Low-frequency variability
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