Monitoring Agricultural Drought Using El Niño and Southern Oscillation Data - Monitoring and Predicting Agricultural Drought: A Global Study - page 37

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process over the tropical Pacific Ocean, its influence is worldwide because
it modifies ocean circulation patterns influencing the weather and climate
anomalies at a global scale.
ENSO-induced droughts are usually severe in nature and last long. Ob-
servational experience indicates that during an ENSO event drought condi-
tions occur over many places in the world, causing severe economical and
societal impacts.
The ENSO data have been used for long-term prediction of droughts.
Usually researchers make use of certain single descriptor indices that are
able to capture relevant information about the events in a simple way.
Although a high level of confidence has been shown, in recent years, in
the capabilities of ENSO data to predict droughts, many uncertainties
still remain. One of the main challenges is the attribution problem. Are
all the droughts due to ENSO? How does it work? Why do some ENSO
events produce drought and while others do not in the same region? The
link between ENSO and drought is still an open book. Much more has
to be done before the global community is able to fully understand and
obtain reliable prediction methods. Meanwhile, ENSO data seem to be
satisfactory for predicting droughts, at least in some major regions of the
world.

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