index_arguments.spi_forecast: arguments for index spi_forecast

In Climandes/ClimIndVis: Calculation, verification and visualisation of climate indices

Description

arguments for index spi_forecast

Usage

## S3 method for class 'spi_forecast'
index_arguments(
  climindvis,
  fc_p,
  timescale = 6,
  ref = NULL,
  distribution = "gamma",
  trend = FALSE,
  trendargs,
  NAmaxAgg = 20,
  ...
)

Arguments

climindvis	Object of type climindvis as returned by make_object which must contain the variable precipitation (prec)
fc_p	Climindvis object with forecast data.
timescale	Integer. Timescale for monthly SPI calculation. The timescale is the window length (in month) of a backward looking running mean. Default = 6.
ref	Vector with start and end year for reference period. If no reference period is specified, the full period is used as reference period.
distribution	A character string naming a distribution of package stats (see for example GammaDist). For more information on the choice of the distribution, see section Details. Default = "gamma".
trend	Logial (or character). Calculates trends with a predefined method for the chosen index. For information on default method, see trend_methods. You can chose to calculate a non-parameteric trend, by setting trend to a character string "MannKendall". This calculates a TheilSen slope and MannKendall test. Default = FALSE.
NAmaxAgg	Maximum number of missing values in daily data of each aggregation period (e.g. in all January values for the whole time series). Value between 0 (=0%; no missing values allowed) and 100 (=100%; all values can be missing values). If the number of missing values is higher than NAmaxAgg the index value for the respective grid point/station is set to NA. Default = 20 (20%).

Details

The SPI calculation is based on the SCI package from Lukas Gudmundsson & James Stagge. For integrating forecasts into the SPI plot, the timeseries of forecast and historical data are checked for the overlapping period. For this period a mean

References

Stagee, J.H. ; Tallaksen, L.M.; Gudmundsson, L.; van Loon, A.; Stahl, K.: Candidate Distributions for Climatological Drought Indices (SPI and SPEI), 2015, International Journal of Climatology, 35, 4027-4040, doi:10.1002/joc.4267.

Climandes/ClimIndVis documentation built on Oct. 24, 2021, 10:52 a.m.