HydPy-Evap-PET-M (month-based adjustment of reference evapotranspiration)

Use evap_pet_m as a plug-in between a main model like lland_dd and another submodel like evap_ret_tw2002 to adjust the reference evapotranspiration given by evap_ret_tw2002 by month.

Integration tests

Note

When new to HydPy, consider reading section Integration Tests first.

Application model evap_pet_m requires no input from another model and does not supply any outlet sequence. Hence, assigning a model instance to a blank Element instance is sufficient:

>>> from hydpy.models.evap_pet_m import *
>>> parameterstep("1d")
>>> from hydpy import Element
>>> element = Element("element")
>>> element.model = model

In our simple test-setting, the submodel of type evap_ret_io supplies different reference evapotranspiration values for two hydrological response units for the last of January and the first of February 2000. evap_pet_m applies individual adjustment factors for both months and “damps” the second unit’s result value:

>>> from hydpy import pub
>>> pub.timegrids = "2000-01-31", "2000-02-02", "1d"
>>> nmbhru(2)
>>> hruarea(0.2, 0.8)
>>> monthfactor.jan = 0.5
>>> monthfactor.feb = 2.0
>>> dampingfactor(1.0, 0.5)
>>> with model.add_retmodel_v1("evap_ret_io"):
...     evapotranspirationfactor(0.8, 1.2)
>>>
>>> from hydpy import IntegrationTest
>>> test = IntegrationTest(element)
>>> test.dateformat = "%Y-%d-%m"
>>> test.inits = ((model.sequences.logs.loggedpotentialevapotranspiration, 0.6),)
>>>
>>> model.retmodel.sequences.inputs.referenceevapotranspiration.series = 1.0, 2.0

>>> test()
Click to see the table
class hydpy.models.evap_pet_m.Model[source]

Bases: Main_RET_PETModel_V1, Sub_ETModel, PETModel_V1

HydPy-Evap-PET-M (month-based adjustment of reference evapotranspiration).

The following “run methods” are called in the given sequence during each simulation step:
The following interface methods are available to main models using the defined model as a submodel:
The following “additional methods” might be called by one or more of the other methods or are meant to be directly called by the user:
Users can hook submodels into the defined main model if they satisfy one of the following interfaces:

  • PETModel_V1 Simple interface for calculating all potential evapotranspiration values in one step.

DOCNAME: DocName = ('Evap-PET-M', 'month-based adjustment of reference evapotranspiration')
OBSERVER_METHODS: ClassVar[tuple[type[Method], ...]] = ()
retmodel: SubmodelProperty

Required submodel that complies with the following interface: PETModel_V1.

REUSABLE_METHODS: ClassVar[tuple[type[ReusableMethod], ...]] = ()
cymodel: CyModelProtocol | None
parameters: parametertools.Parameters
sequences: sequencetools.Sequences
masks: masktools.Masks
class hydpy.models.evap_pet_m.ControlParameters(master: Parameters, cls_fastaccess: type[FastAccessParameter] | None = None, cymodel: CyModelProtocol | None = None)

Bases: SubParameters

Control parameters of model evap_pet_m.

The following classes are selected:

  • NmbHRU() The number of separately modelled hydrological response units [-].

  • HRUArea() The area of each hydrological response unit [km²].

  • MonthFactor() Factor for converting general potential evaporation or evapotranspiration (usually grass reference evapotranspiration) to month-specific potential evaporation or evapotranspiration [-].

  • DampingFactor() Damping factor (temporal weighting factor) for potential evapotranspiration [-].

class hydpy.models.evap_pet_m.DerivedParameters(master: Parameters, cls_fastaccess: type[FastAccessParameter] | None = None, cymodel: CyModelProtocol | None = None)

Bases: SubParameters

Derived parameters of model evap_pet_m.

The following classes are selected:

  • MOY() References the “global” month of the year index array [-].

  • HRUAreaFraction() The area fraction of each hydrological response unit [-].

class hydpy.models.evap_pet_m.FluxSequences(master: Sequences, cls_fastaccess: type[TypeFastAccess_co] | None = None, cymodel: CyModelProtocol | None = None)

Bases: FluxSequences

Flux sequences of model evap_pet_m.

The following classes are selected:
class hydpy.models.evap_pet_m.LogSequences(master: Sequences, cls_fastaccess: type[TypeFastAccess_co] | None = None, cymodel: CyModelProtocol | None = None)

Bases: LogSequences

Log sequences of model evap_pet_m.

The following classes are selected: