Suitability of a lumped rainfall–runoff model for flashy tropical watersheds in New Caledonia

Abstract

The GR4H lumped hourly rainfall-runoff model was assessed for its integration in a ridge-to-reef modelling framework. Particular attention was paid to rainfall representation, robustness of parameter estimates and ability to reproduce main runoff features. The study was conducted in four tropical mountainous watersheds in New Caledonia, exposed to intense rainfall events, large annual climatic variations triggered by El Niño oscillation, and wildfires. The inverse distance and elevation weighting algorithm outperformed other classical rainfall interpolation methods under data-limited conditions. The time-span of data needed for robust calibration was site-specific and varied from 6-7 years to 10 years, which may be linked to El Niño events and to wildfires. With sufficient data, simulation quality was equivalent during calibration and validation periods. The GR4H model was generally able to simulate both flash floods and large annual variations. The model was more reliable when simulating wet years and watersheds not subject to land-cover changes.

Hydrological regimes in a tropical valley of New Caledonia (SW Pacific): Impacts of wildfires and invasive fauna

“…The SCAR available data are used for both calibration and validation of the model as proposed by Desclaux, Lemonnier, Genthon, Soulard, and Le Gendre (2018). The complete model is adjusted on the whole period, while two additional models are adjusted on the October 2018–January 2019 and on the February 2019–May 2019 sub‐periods; they are termed as models S1 and S2.…”

Integrating Microbial Community Assembly and Fluid Kinetics to Decouple Nitrogen Dynamics in an Urban Channel Confluence

“…Then, the mean 2-D velocity of each interval was used for drawing of flow field. Inverse distance weighted interpolation, which is commonly used for hydraulic calculation, − was adopted to predict velocities in unmeasured areas. All calculation processes were conducted in MATLAB, and Tecplot 360 was used to visualize the outcome.…”

Tropical mangrove forests as a source of dissolved rare earth elements and yttrium to the ocean

“…Overall, the hydrologic regime is characterized by high annual variability of rainfall amount and extreme events. Moreover, high and steep watersheds are associated with flash floods and thus rapid water transfer to the lagoons (Desclaux et al, 2018).…”