Climate affects malaria transmission through a complex network of causative pathways. We seek to evaluate the impact of hypothetical
climate change scenarios on malaria transmission in the Sahel by using a novel mechanistic, high spatial- and temporal-resolution
coupled hydrology and agent-based entomology model. The hydrology model component resolves individual precipitation events
and individual breeding pools. The impact of future potential climate shifts on the representative Sahel village of Banizoumbou,
Niger, is estimated by forcing the model of Banizoumbou environment with meteorological data from two locations along the
north–south climatological gradient observed in the Sahel—both for warmer, drier scenarios from the north and cooler, wetter
scenarios from the south. These shifts in climate represent hypothetical but historically realistic climate change scenarios.
For Banizoumbou climatic conditions (latitude 13.54 N), a shift toward cooler, wetter conditions may dramatically increase
mosquito abundance; however, our modeling results indicate that the increased malaria transmissibility is not simply proportional
to the precipitation increase. The cooler, wetter conditions increase the length of the sporogonic cycle, dampening a large
vectorial capacity increase otherwise brought about by increased mosquito survival and greater overall abundance. Furthermore,
simulations varying rainfall event frequency demonstrate the importance of precipitation patterns, rather than simply average
or time-integrated precipitation, as a controlling factor of these dynamics. Modeling results suggest that in addition to
changes in temperature and total precipitation, changes in rainfall patterns are very important to predict changes in disease
susceptibility resulting from climate shifts. The combined effect of these climate-shift–induced perturbations can be represented
with the aid of a detailed mechanistic model.
Keywords malaria - climate change - hydrology - anopheles mosquitoes - agent-based modeling