Abstract:
Abstract: Many parts of Sri Lanka are vulnerable to extreme
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was focused on a trend analysis of climate extremes derived
from daily rainfall records. The daily rainfall data from 13
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regions in Sri Lanka for the period 1961–2010 were chosen.
The analysis was carried out separately for summer half year
(March-August) and winter half year (September-February) to
capture the possible changes in two growing seasons, Yala and
Maha. Magnitudes of trends were derived using linear regression
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the Mann-Kendall test. Spatial maps were used to study the
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were found to be isolated events without coherent increasing or
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(decreasing) trends were observed for number of dry days (wet
days) ranging from 1.1 to 3.1 days/decade in most parts of the
island during the summer half year, except for the coastal areas
of the dry zone. No increasing or decreasing trends in extremes
were observed for the winter half year. Based on the analysis,
it was concluded that there is widespread climate change
leading to increasing (decreasing) dry days (wet days) during
the summer half year receiving rainfall predominantly from the
South-West monsoon. However, mixed results were obtained
for the winter half year.
