TY - JOUR
T1 - A parsimonious daily water balance model based on the proportionality hypothesis
AU - Wu, Shuyue
AU - Zhao, Jianshi
AU - Sivapalan, Murugesu
N1 - Publisher Copyright:
© 2024 Elsevier B.V.
PY - 2025/3
Y1 - 2025/3
N2 - Daily water balance modeling is important for both hydrological science and water resources management. The majority of daily water balance models express the output fluxes (including runoff and evapotranspiration) as independent functions of soil moisture store(s), and as such they involve a large number of parameters, the estimation of which is a major challenge. In this paper, following a downward approach, we develop a parsimonious daily water balance model, DPWM, based on the Proportionality Hypothesis, which assumes that a proportional relation exists among different hydrological components, which contributes to model parsimony. DPWM includes just 5 parameters, 3 of which are taken up to capture water balance partitioning and 2 for runoff routing. With daily precipitation and potential evapotranspiration as inputs, DPWM invokes Proportionality Hypothesis to generate four main daily hydrological components, namely evapotranspiration, storage change, fast runoff and slow runoff. DPWM was applied to simulate daily streamflow (Q) and evapotranspiration (ET) in 671 US catchments covering a wide range of climates and landscapes, and showed catchment-average KGE(Q), KGE(1/Q) and KGE(ET) of 0.64, 0.68, 0.75 respectively. DPWM is seen to capture temporal variability of streamflow in rainfall-dominated humid catchments particularly well. DPWM shows comparable performance with the MARRMoT version of the XINANJIANG model, a traditional 12-parameter rainfall-runoff model that shows top performance amongst over 30 conceptual rainfall-runoff models. DPWM's performance on KGE(1/Q) is even higher than that of XINANJIANG model. These results provide evidence that the Proportionality Hypothesis is useful for modeling daily water balance across a wide range of climates and landscape characteristics.
AB - Daily water balance modeling is important for both hydrological science and water resources management. The majority of daily water balance models express the output fluxes (including runoff and evapotranspiration) as independent functions of soil moisture store(s), and as such they involve a large number of parameters, the estimation of which is a major challenge. In this paper, following a downward approach, we develop a parsimonious daily water balance model, DPWM, based on the Proportionality Hypothesis, which assumes that a proportional relation exists among different hydrological components, which contributes to model parsimony. DPWM includes just 5 parameters, 3 of which are taken up to capture water balance partitioning and 2 for runoff routing. With daily precipitation and potential evapotranspiration as inputs, DPWM invokes Proportionality Hypothesis to generate four main daily hydrological components, namely evapotranspiration, storage change, fast runoff and slow runoff. DPWM was applied to simulate daily streamflow (Q) and evapotranspiration (ET) in 671 US catchments covering a wide range of climates and landscapes, and showed catchment-average KGE(Q), KGE(1/Q) and KGE(ET) of 0.64, 0.68, 0.75 respectively. DPWM is seen to capture temporal variability of streamflow in rainfall-dominated humid catchments particularly well. DPWM shows comparable performance with the MARRMoT version of the XINANJIANG model, a traditional 12-parameter rainfall-runoff model that shows top performance amongst over 30 conceptual rainfall-runoff models. DPWM's performance on KGE(1/Q) is even higher than that of XINANJIANG model. These results provide evidence that the Proportionality Hypothesis is useful for modeling daily water balance across a wide range of climates and landscape characteristics.
KW - Catchment water balance
KW - Daily scale hydrological modeling
KW - Proportionality Hypothesis
KW - Runoff
UR - http://www.scopus.com/inward/record.url?scp=85211143218&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85211143218&partnerID=8YFLogxK
U2 - 10.1016/j.jhydrol.2024.132414
DO - 10.1016/j.jhydrol.2024.132414
M3 - Article
AN - SCOPUS:85211143218
SN - 0022-1694
VL - 649
JO - Journal of Hydrology
JF - Journal of Hydrology
M1 - 132414
ER -