Implementing the Blaney-Criddle formulation for estimating reference crop evapotranspiration.

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`data` |
A list of data which contains the following items (climate variables) required by Blaney-Criddle formulation: |

`constants` |
A list named |

`ts` |
Must be either |

`solar` |
Must be either \codesunshine hours or |

`height` |
Must be |

`...` |
Dummy for generic function, no need to define. |

The alternative calculation options can be selected through argument `solar`

, please see `Arguments`

for details.

Height adjustment for the estimations is available through argument `height`

, please see `Arguments`

for details.

The function prints a calculation summary to the screen containing the following elements:

- ET model name and ET quantity estimated

- Evaporative surface

- Option for calculating solar radiation (i.e. the value of argument `solar`

)

- If height adjustment has been applied on results (i.e. the value of argument `height`

)

- Time step of the output ET estimates (i.e. the value of argument `ts`

)

- Units of the output ET estimates

- Time duration of the ET estimation

- Number of ET estimates obtained in the entire time-series

- Basic statistics of the estimated ET time-series including *mean*, *max* and *min* values.

The function also generates a list containing the following components, which is saved into a `csv`

file named as *ET_BlaneyCriddle.csv* in the working directory:

`ET.Daily` |
Daily aggregated estimations of Blaney-Criddle reference crop evapotranspiration. |

`ET.Monthly` |
Monthly aggregated estimations of Blaney-Criddle reference crop evapotranspiration. |

`ET.Annual` |
Annually ggregated estimations of Blaney-Criddle reference crop evapotranspiration. |

`ET.MonthlyAve` |
Monthly averaged estimations of daily Blaney-Criddle reference crop evapotranspiration. |

`ET.AnnualAve` |
Annually averaged estimations of daily Blaney-Criddle reference crop evapotranspiration. |

`ET_formulation` |
Name of the formulation used which equals to |

`ET_type` |
Type of the estimation obtained which is |

`message1` |
A message to inform the users about how solar radiation has been calculated by using which data. |

`message3` |
A message to inform the users about if height adjustment has been applied to calculated Blaney-Criddle reference crop evapotranspiration. |

Danlu Guo

McMahon, T., Peel, M., Lowe, L., Srikanthan, R. & McVicar, T. 2012. *Estimating actual, potential, reference crop and pan evaporation using standard meteorological data: a pragmatic synthesis*. Hydrology and Earth System Sciences Discussions, 9, 11829-11910.

Allen, R.G.Brockway, C.E. 1983, *Estimating consumptive use on a statewide basis*. Advances in Irrigation and Drainage@ sSurviving External Pressures, ASCE, pp. 79-89.

Allen, R. & Pruitt, W. 1986. *Rational Use of The FAO Blaney-Criddle Formula*. Journal of Irrigation and Drainage Engineering, 112, 139-155.

Frevert, D.K., Hill, R.W.Braaten, B.C. 1983, *Estimation of FAO evapotranspiration coefficients*, Journal of Irrigation and Drainage Engineering, vol. 109, no. 2, pp. 265-270.

`ET`

,`data`

,`defaultconstants`

,`constants`

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