Modeling the role of rainfall patterns in seasonal malaria transmission

TitleModeling the role of rainfall patterns in seasonal malaria transmission
Publication TypeJournal Article
Year of Publication2012
AuthorsBomblies, A
JournalClimatic Change
Pagination673 - 685
Date Published2012/06

Seasonal total precipitation is well known to affect malaria transmission because
Anopheles mosquitoes depend on standing water for breeding habitat. However, the withinseason temporal pattern of the rainfall influences persistence of standing water and thus
rainfall patterns can also affect mosquito population dynamics in water-limited environments. Here, using a numerical simulation, I show that intraseasonal rainfall pattern
accounts for 39% of the variance in simulated mosquito abundance in a Niger Sahel village
where malaria is endemic but highly seasonal. I apply a field validated coupled hydrology
and entomology model. Using synthetic rainfall time series generated using a stationary
first-order Markov Chain model, I hold all variables except hourly rainfall constant, thus
isolating the contribution of rainfall pattern to variance in mosquito abundance. I further
show the utility of hydrology modeling using topography to assess precipitation effects by
analyzing collected water. Time-integrated surface area of pools explains 70% of the
variance in simulated mosquito abundance from a mechanistic model, and time-integrated
surface area of pools persisting longer than 7 days explains 82% of the variance.
Correlations using the hydrology model output explain more variance in mosquito
abundance than the 60% from rainfall totals. I extend this analysis to investigate the
impacts of this effect on malaria vector mosquito populations under climate shift scenarios,
holding all climate variables except precipitation constant. In these scenarios, rainfall mean
and variance change with climatic change, and the modeling approach evaluates the impact
of non-stationarity in rainfall and the associated rainfall patterns on expected mosquito

Short TitleClimatic Change
Refereed DesignationRefereed
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