Monitoring and Managing Agricultural Drought in India - Monitoring and Predicting Agricultural Drought: A Global Study - page 304

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issued to the state and central government agencies. The bulletin consists of
three sections. The first section contains color-coded NDVI imageries of the
state with district boundaries superimposed. The second section compares
district level greenness during reporting year with the previous two years.
The third section consists of a district level assessment of drought preva-
lence and persistence and the relative severity levels based on the extent of
NDVI anomaly (Chakraborti, 2000). NDVI anomalies are interpreted in
terms of moisture stress condition after verifying false alarms due to ex-
cessive rainfall or flooding, cloud contamination, poor time-composition,
difference in seasonal growth cycle, and so on. Based on the relationship
between NDVI and major crop yields, the early warning on relative yield
assessment is provided from August onward. It is possible to further im-
prove the performance of satellite data-based monitoring system by deter-
mining the dates of the commencement and termination of phenological
phases using biometeorological time scale or crop growth models (Boken
and Shaykewich, 2002; chapter 1). These models can help select the satellite
data for the critical phases of the crop when yields are most significantly
affected by drought conditions. In addition, Indian Remote Sensing satel-
lite data are used for drought assessment by coupling satellite data analysis
with adequate ground information, such as reduction in harvest area and
water availability, reduced production of fodder, and other socio-economic
factors (Chakraborti, 2000).

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D rought Mitigation
The following are some strategies for drought mitigation that were devel-
oped in India since the 1970s.

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C rop Planning

Based on rainfall analysis, water availability periods were identified for
several locations in India in order to escape droughts and plan crop sowing
according to the water availability (Srinivasamurthy, 1976). Figure 23.4
shows four different scenarios that characterize monsoon behavior in India:
(1) Normal onset of monsoon followed by adequate amount of rainfall,
(2) normal onset of monsoon followed by inadequate amount of rainfall,
(3) late onset of monsoon followed by adequate amount of rainfall, and
(4) late onset of monsoon followed by inadequate amount of rainfall. For
each scenario, a different strategy is adopted to minimize the impact of
drought on crop production.
In the first scenario, the crop-growing period varies from 90 to 120
days, and cereal crops such as sorghum, pearl millet, maize, pulses such as
cowpea, mungbean, blackgram, and oilseeds such as sesame, castor, and
groundnut with high density planting followed by leguminous/fodder crop
can be grown for maximum profits. In the second scenario, mid-season
corrections such as reducing plant population, weeding, and creating soil