Monthly maps of ESI, LAI’ and TRMM’ showing the evolution of
moisture and crop conditions over northeastern Brazil during these
two growing seasons are provided in Fig.8. The three indicators capture
the cycle of early-season (November to January) moisture availability,
aiding the primary corn crop grown in western BA, and mid-year
drought in both years in northeastern BA where the bulk of the safrinha
corn crops are grown. As indicated in Fig. 7a, ESI indicated a larger amplitude in favorable (positive anomalies, peaking around week 8) and
stressed (negative anomalies, week 32–40) conditions during these
two years, resulting in higher correlations for ESI with both first and second corn crop yields (Fig. 7b). The oscillating moisture conditions in
these two growing seasons led to a strong early season anticorrelation
(red tones) with safrinha corn yields in BA and the NE region, particularly for ESI. This anticorrelation feature is to some extent an artifact of the
precise sequence of moisture events that occurred in this region over
the period of record, but does indicate that this region is highly susceptible to rapid changes in water availability.