B. KUMPHON ET AL.
Copyright © 2012 SciRes. JWARP
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awareness weeks are weeks 33 to 36, with very heavy
rain (84 to 110 mm.). This is useful information for the
hydro-meteorologists, and for reservoir planners who
manage water release and storage before and during the
awareness weeks 33 to 36. The best weeks for agri-
culturists to plan drying processes for crops are 1 to 6, 8,
10 and 45 to 52 because there is then no rainfall.
5. Conclusion
For the planning and design of crop scheduling and the
design of water management in Northeast Thailand, the
distribution of weekly rainfall was investigated from data
on weekly rainfall for a part of Chi River Basin sur-
rounding the Lampao Reservoir. The data is fitted well
by K4D with L-Moments estimation, and there is some
evidence for a generalized Pareto distribution. There is
usually one distribution that passes the goodness-of-fit
test. Although, ther e might be more than one distribu tion
for this relatively small region (from the family of such
distributions). For the estimated rainfall at the specific
probability 0.75, there is low to no rainfall in the dry
season, which is the best time for drying crops or any
associated activity that has no water requirement. On the
other hand, there is very high value of rainfall in the
rainy season.
6. Acknowledgements
Financ ial support was provided by the Faculty of Scienc e ,
and Mahasarakham University Development Fund, Maha-
sarakham University. The data was provided by the Hy-
drology and Water Management Center for the upper
north eastern Royal Irrigation department, Thailand. The
author thanks Professor Roger Hosking for his support
and helpful suggestions.
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