loading page

Incorporating a Rainfall Intensity Modification Factor γ into the Ia-S Relationship in the NRCS-CN Method
  • +3
  • Pengcheng Hu,
  • Jia Tang,
  • Jihui Fan,
  • Shumiao Shu,
  • Zhaoyong Hu,
  • bo zhu
Pengcheng Hu
Institute of Mountain Hazards and Environment Chinese Academy of Sciences

Corresponding Author:[email protected]

Author Profile
Jia Tang
Institute of Mountain Hazards and Environment Chinese Academy of Sciences
Author Profile
Jihui Fan
Institute of Mountain Hazards and Environment Chinese Academy of Sciences
Author Profile
Shumiao Shu
Institute of Mountain Hazards and Environment Chinese Academy of Sciences
Author Profile
Zhaoyong Hu
Institute of Mountain Hazards and Environment
Author Profile
bo zhu
Institute of Mountain Hazards and Environment, the Chinese Academy of Sciences, Chengdu
Author Profile

Abstract

Rainfall intensity is a key factor that influences the processes of infiltration and runoff generation on the surface soil. However, the Natural Resources Conservation Service runoff curve number (NRCS-CN) method, which is widely used to simulate direct runoff, does not consider the impact of rainfall intensity on the simulation results. Hence, this study incorporates a rainfall intensity modification factor (γ) into the Ia-S relationship in the NRCS-CN method. The results show that the modified method, the NRCS-CN-γ method, improves the efficiency, reduces the impact of variable rainfall intensity on the simulation results and reduces the relative errors caused by the changes in CN to approximately one-third of the original errors in the NRCS-CN method. Consequently, the NRCS-CN-γ method contributes to a more accurate simulation and prediction of direct runoff in monsoon regions where rainfall intensity greatly varies, especially under climate change.