qm.empqm.doy.fa: Short The actual QM function considering the DOY and...

Description Usage Arguments Details Value Author(s) Examples

View source: R/qm.empqm.doy.fa.R

Description

qm.empqm.doy.fa is the actual QM function considering the day-of-year (DOY) and including frequency adaptation for precipitation.

Usage

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qm.empqm.doy.fa(series, doy.series, cdf.mod, cdf.obs, cdf.obs.wet, cor.fun,
  fwet.obs, fwet.mod, pr.wet, method = c("linear", "bin"), var,
  output.diag = FALSE, minq, maxq, incq)

Arguments

series

Time series of modelled data, e.g. transient (control+) scenario series.

doy.series

Corresponding series of DOYs (output of function qm.doystring).

cdf.mod

CDF of the modelled time series in the calibration period, estimated with function qm.cdf.doy(...) (matrix[365,nquantiles]).

cdf.obs

CDF of the observed time series in the calibration period, estimated with function qm.cdf.doy(...) (matrix[365,nquantiles]).

cdf.obs.wet

CDF of the observed time series in the calibration period for wet days only, estimated with function qm.cdf.doy(...) (matrix[365,nquantiles]).

fwet.obs

Observed wet day frequency for each DOY (vector[365], output of function qm.cdf.doy).

fwet.mod

Modelled wet day frequency for each DOY (vector[365], output of function qm.cdf.doy).

pr.wet

Internal precipitation wet day threshold [mm/day].

method

QM method: "binary" -> correction for closest quantile is used, "linear" -> linear interpolation of correction function between lower and upper quantile.

var

Variable to correct.

output.diag

Diagnostic QM console output (TRUE) or not (FALSE); default: FALSE.

minq

Minimum quantile for correction function [0.01 .. 0.99]; note: should not be 0 (for correct handling of extremes)!

maxq

Maximum quantile for correction function [0.01 .. 0.99]; note: should not be 1 (for correct handling of extremes)!

incq

Quantile increment for correction function (bin size).

corr.fun

Additive correction function (cdf A - cdf B), obtained by function qm.corfun.doy(...).

Details

The function estimates the index (quantile) in which an observation falls with respect to the calibration period. Based on this quantile (and the DOY) a correction is applied, the final quantile map. If the number of dry days in the modelled time series is larger than the number in the reference series, an additional frequency adaptation is carried out: for modelled dry days it is first determined (using a random number) if the corrected value should be zero as well. If not, a random value is drawn from the wet day distribution. Old and new extremes beyond the min and max percentile considered are corrected according to the correction of the min and max percentile, respectively (first and last quantile considered therefore have to be 0.01 and 0.99 -> check in function qm.doqm).

Value

List of 3: $qm.input.series: Input series to QM (input argument series). $qm.corrected.series: Corrected series. $quantile.index: A series of quantile indices wrt. simulated series in calibration period.

Author(s)

Jan Rajczak (ETH Zurich), Sven Kotlarski (MeteoSwiss)

Examples

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## Not run: 
# Carry out DOY-dependent QM with frequency adaptation. Standard quantiles.
# Variable: precipitation. Wet-day treshold of 0.1 mm/day. Linear QM,
# diagnostic terminal output.
qm.empqm.doy.fa(series, doy.series, cdf.modelled, cdf.observed, cdf.observed.wet, correction.function, fwet.obs, fwet.mod, 0.1, 'linear', 'pr', TRUE, 0.01, 0.00, 0.01)

## End(Not run)

SvenKotlarski/qmCH2018 documentation built on July 14, 2019, 7:39 p.m.