Use of near-real-time satellite precipitation data and machine learning
to improve extreme runoff modeling
Abstract
Extreme runoff modeling is hindered by the lack of sufficient and
relevant ground information and the low reliability of physically-based
models. The authors propose to combine precipitation Remote Sensing (RS)
products, Machine Learning (ML) modeling, and hydrometeorological
knowledge to improve extreme runoff modeling. The approach applied to
improve the representation of precipitation is the object-based
Connected Component Analysis (CCA), a method that enables classifying
and associating precipitation with extreme runoff events. Random Forest
(RF) is employed as a ML model. We used 2.5 years of nearly-real-time
hourly RS precipitation from the PERSIANN-CCS and IMERG-early run
databases (spatial resolutions of 0.04 o and 0.1 o , respectively), and
runoff at the outlet of a 3391 km 2-basin located in the tropical Andes
of Ecuador. The developed models show the ability to simulate extreme
runoff for the cases of long-duration precipitation events regardless of
the spatial extent, obtaining Nash-Sutcliffe efficiencies (NSE) above
0.72. On the contrary, we found an unacceptable model performance for a
combination of short-duration and spatially-extensive precipitation
events. The strengths/weaknesses of the developed ML models are
attributed to the ability/difficulty to represents complex
precipitation-runoff responses.