18/04/2005 - Climate change
could mean big trouble for farmers in India,
as it threatens to upset the monsoon season.
Changing weather patterns might even lead
to famine, due to dangerous impacts on agriculture.
The wet summer monsoon season is vital for
India and other South-Asian countries, because
it brings most of the annual rainfall that
is critical for agriculture. Large areas of
western and central India receive more than
90 percent of their total annual rainfall
during the summer monsoon season.
Indian farmers rely on the timing and predictability
of the monsoon season to grow crops. For thousands
of years, farming has been carefully timed
to coincide planting with the onset of monsoon
rains in order to maximize crop production.
Increasing temperature will lead to trouble
Rising temperature, due to global warming,
will affect the amount of rainfall and the
timing that monsoon seasons hit India.
Because India’s economy is heavily based
on agriculture, the importance of accurately
predicting the timing and severity of monsoons
is extremely important.
For example, if monsoon rains do not arrive
on time, farmers will be forced to wait and
run the risk of planting their crops late.
This will result in fewer crops and potentially
famine. If monsoon rains are too severe, seedlings
that were planted could be washed away, resulting
in massive food shortages.
Accurate timing can avoid agricultural losses
A number of recent scientific studies have
acknowledged this risk and have examined the
factors which create and influence monsoons
in an attempt to better predict future monsoon
seasons.
One such study identifies the factors that
influence monsoon intensity and timing; temperature,
rainfall, and the depth at which sea water
drastically changes temperature and density
(the barrier layer). This study, published
in the journal Geophysical Research Letters,
has modeled these factors and has been able
to use the barrier layer to predict monsoon
onset two months before it happens.
This study shows that the prediction of monsoon
onset is feasible. However, WWF warns that
changes in the earth’s climate are upon us.
We must understand the causes and the impacts
in order to push for the right solutions.
Source: Masson et al. 2005. Impact of barrier
layer on winter-spring variability of the
southeastern Arabian Sea. GEOPHYSICAL RESEARCH
LETTERS, VOL. 32, L07703, doi:10.1029/ 2004GL021980.
