DataAltiExtrapolation_Valery {airGR} | R Documentation

## Altitudinal extrapolation of precipitation and temperature series described by A. Valery

### Description

Function which extrapolates the precipitation and air temperature series for different elevation layers (method from Valéry, 2010).

### Usage

    DataAltiExtrapolation_Valery(DatesR, Precip, PrecipScale = TRUE,
      TempMean, TempMin = NULL, TempMax = NULL,
      ZInputs, HypsoData, NLayers, verbose = TRUE)

### Arguments

`DatesR` | [POSIXt] vector of dates
`Precip` | [numeric] time series of daily total precipitation (catchment average) [mm/time step]
`PrecipScale` | (optional) [boolean] indicating if the mean of the precipitation interpolated on the elevation layers must be kept or not, required to create CemaNeige module inputs, default = `TRUE` (the mean of the precipitation is kept to the original value)
`TempMean` | [numeric] time series of daily mean air temperature [°C]
`TempMin` | (optional) [numeric] time series of daily min air temperature [°C]
`TempMax` | (optional) [numeric] time series of daily max air temperature [°C]
`ZInputs` | [numeric] real giving the mean elevation of the Precip and Temp series (before extrapolation) [m]
`HypsoData` | [numeric] vector of 101 reals: min, q01 to q99 and max of catchment elevation distribution [m]
`NLayers` | [numeric] integer giving the number of elevation layers requested [-]
`verbose` | (optional) [boolean] boolean indicating if the function is run in verbose mode or not, default = `TRUE`

### Details

Elevation layers of equal surface are created the 101 elevation quantiles (`HypsoData`) and the number requested elevation layers (`NLayers`).
Forcing data (precipitation and air temperature) are extrapolated using gradients from Valery (2010). (e.g. gradP = 0.0004 [m-1] for France and gradT = 0.434 [°C/100m] for January, 1st).
This function is used by the `CreateInputsModel` function.

### Value

list containing the extrapolated series of precip. and air temp. on each elevation layer

$LayerPrecip | [list] list of time series of daily precipitation (layer average) [mm/time step]
$LayerTempMean | [list] list of time series of daily mean air temperature (layer average) [°C]
$LayerTempMin | [list] list of time series of daily min air temperature (layer average) [°C]
$LayerTempMax | [list] list of time series of daily max air temperature (layer average) [°C]
$LayerFracSolidPrecip | [list] list of time series of daily solid precip. fract. (layer average) [-]
$ZLayers | [numeric] vector of median elevation for each layer

### Author(s)

Laurent Coron, Audrey Valéry, Olivier Delaigue, Pierre Brigode, Guillaume Thirel

### References

Turcotte, R., L.-G. Fortin, V. Fortin, J.-P. Fortin and J.-P. Villeneuve (2007). Operational analysis of the spatial distribution and the temporal evolution of the snowpack water equivalent in southern Quebec, Canada, Nordic Hydrology, 38(3), 211. doi:10.2166/nh.2007.009.
Valéry, A. (2010), Modélisation précipitations-débit sous influence nivale ? : Elaboration d'un module neige et évaluation sur 380 bassins versants. PhD thesis (in french), AgroParisTech, Paris, France.
USACE (1956), Snow Hydrology, pp. 437. U.S. Army Coprs of Engineers (USACE) North Pacific Division, Portland, Oregon, USA.

### See Also

`CreateInputsModel`, `RunModel_CemaNeigeGR4J`

[Package airGR version 1.3.2.23 Index]