Test alternative onset definitions based on precipitation and on soil water balance

Host Institution: International Center for Tropical Agriculture (CIAT).

 Location:  KG 563 ST, P.O. Box 1269, Kacyiru, Kigali, Rwanda.

 Supervisors: Dr. Desire M. Kagabo (Ph.D), Scientist, Climate Services for Agriculture, CIAT (The research team from CIAT or CCAFS, IRI, University of Reading working with the Rwanda Climate Services for Agriculture Project will be available to supervise the interns).


Project Description :

Decision support for time of planting has been identified as a priority in Rwanda, but the current rainfall-based onset definition seems to be problematic.  It seems to show unrealistic differences in onset date across the country, and some station locations that behave very differently than nearby locations.  We think it is very sensitive to small biases in, e.g., rainfall frequency, associated with the merging and gridding process.  Intuitively, soil water balance, modeled with daily rainfall data, should better capture what is important from a crop germination and survival standpoint, than the current rainfall-based criteria.  We also think water balance modeling might be less sensitive to small timing and threshold effectives.  I could envision this involving two interns.

Develop soil water balance-based onset model, with flexible parameters.

Test consistency of rainfall- and water balanced-based onset dates, in space and across years.

Identify appropriate metrics for evaluation, e.g., time series or spatial surveys of actual planting date, expert or farmer judgment about appropriate planting date; and evaluate ability of parameterized alternative onset definitions to capture variability of these metrics in space and/or across years.

Evaluate sensitivity of alternate onset definitions to errors associated with rainfall merging and gridding.

Applications for this internship should be submitted via the online application system, stating clearly the title of the internship.

Deadline for applications: June 30th, 2018 – 11:59 PM (EAT).

Any inquiries about these internships should be sent to: