Stochastic modeling of rainfall and runoff for Wadi Jizan in the Kingdom of Saudi Arabia

Abstract EN

-Hydrologi c variables when they arc normalized by var ious tra nsforma tio n techni ques can be used for stochas tic modelin g, so th at tim e se ries becom es mor e att ractive for hydr ologi c for ecastin g throu gh simulation procedure .

Thi s pape r discusses the applica tion procedure of the auto reg ressive models of two orders using monthly ra infall-ru noff data in Wadi Jizan.

Wadi Jizan, locat ed nc ar the Red Sea Coast of the southwes te rn part of the Kingdom , is se lected as the case study.

The applicatio n of th e mod els indi cates th at designi ng of the res e rvoir volume with 70 x 10" rn' capacity is o n th e sa fe side and a littl e o ver than the simulated me an annual ru noff volume of 52 x 10" m' .

It se rves multifunction obj ectives fo r flood protection , irr igation a nd rech ar ging to gro undwater tabl e .

Th e simula ted poin t annual ra infall depth found as 269 .66 rnrn is very clo se to th e station mean whereas the areal average precipitation depth of the basin is two thir ds higher than th e point rainfall record (282.2 1 mrn) measured at th e dam site .