unifhycontrib.gr4

class unifhycontrib.gr4.OpenWaterComponent

The GR4 (“Génie Rural à 4 paramètres” [in French]) model is a bucket-type rainfall-runoff model featuring four parameters.

It is typically used as a daily model, i.e. GR4J model (Perrin et al., 2003). It can also be used at other temporal resolutions, e.g. hourly in GR4H model, provided an adjustment in its time-dependent parameter and constant values is performed (Ficchì et al., 2016). The model has recently been expressed in a state-space formulation (Santos et al., 2018).

This version of the GR4 model is based on its explicit state-space formulation and its recommended temporal resolutions are daily or hourly. With either of these resolutions, time-dependent parameters x2, x3, x4, and constant nu are expected for the daily case and they are adjusted accordingly if temporal resolution is not daily.

The openwater component of the GR4 model comprises the runoff routing using the routing store, and the inter-catchment groundwater exchange.

Contributors

Thibault Hallouin [1,2]

Affiliations

Department of Meteorology, University of Reading
National Centre for Atmospheric Science

Licence

GPL-2.0

Codebase

https://github.com/unifhy-org/unifhycontrib-gr4

Inwards

name: surface_runoff_flux_delivered_to_rivers
units: kg m^-2 s^-1
from: subsurface
method: mean

Outputs

name: outgoing_water_volume_transport_along_river_channel
units: kg m^-2 s^-1
description: streamflow at outlet

Parameters

name: x2
units: kg m^-2 d^-1

name: x3
units: kg m^-2

Constants

name: gamma
description: routing outflow exponent
units: 1
default_value: 5.0e+00

name: omega
description: exchange exponent
units: 1
default_value: 3.5e+00

name: phi
description: partition between routing store and direct flow
units: 1
default_value: 9.0e-01

States

name: routing_store
units: kg m^-2

SpaceDomain Properties

name: land_sea_mask
required: False

name: flow_direction
required: False

name: cell_area
required: False