index_arguments.rainy_season_start: arguments for index rainy_season_start

View source: R/calc_indices_get_arguments.R

index_arguments.rainy_season_startR Documentation

arguments for index rainy_season_start

Description

arguments for index rainy_season_start

Usage

## S3 method for class 'rainy_season_start'
index_arguments(
  climindvis,
  rs_method,
  days,
  th,
  th1 = 25,
  th2 = 20,
  dd_th = 1,
  nval = NA,
  mdays,
  mcdd,
  trend = FALSE,
  NAmaxTrend = 20,
  NAdays = 0,
  ...
)

Arguments

climindvis

Object of type climindvis as returned by make_object which must contain the variable precipitation (prec)

days

Number of consecutive days of which precipitation sum is higher than threshold <<th>>

th

Threshold for precipitation sum of <<days>> consecutive days in mm

dd_th

Dry day threshold

nval

Value which is returned if criteria for start of rainy season are not met, default=NA. Other values can be set to distinguish between years where data is NA and years where criteria of index are not met

mdays

Number of days to check for <<mcdd>>

mcdd

Maximum consecutive dry days in the next <<mdays>> days

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.

NAmaxTrend

Maximum number of years in time series of index which are missing values. Value between 0 (=0%); no years with missing values allowed) and 100 (=100%); all years can be missing values). If exceeded, the trend is set to NA for the respective grid point/station. Note that the value is relative to the length of the time series. Default = 20 (20%).

NAdays

Number of NA days allowed per decade for index <<sos>>. Default=0.

rs_method:

method for calculation of index (further indicator arguments for each rs_method are given in brackets and defined below, arguments without default that have to be provided are in bold font ):

  • climandes (nval): wet day and precipitation sum(5days) > 8mm and maximum number of consecutive dry days within the next 30 days <=7 (definition from Sedlmeier et al.,submitted )

  • jd (nval): 3 of 5 days > 0.1mm & precipitation sum(5days) > 25mm and maximum number of consecutive dry days within the next 30 days >=7 (definition from Jolliffe and Dodd, 1994 )

  • garcia (nval): precipitation sum(3days) > 20mm and maximum number of consecutive dry days within the next 30 days <=10 (definition from Garcia et al.,2007 )

  • gurgiser (nval): wet day and precipitation sum(7days) > 10mm and number of consecutive wet days within the next 30 days > 10 (definition from Gurgiser et al.,2017)

  • consec_th (days,th,nval): wet day and sum of user defined number of consecutive days (<<days>>) above user defined threshold (<<th>>) (e.g. sum of 4 days > 10mm)

  • consec_th_maxcdd (days,th,mdays,mcdd,nval): wet day and sum of user defined number of consecutive days (<<days>>) above user defined threshold (<<th>>) and maximum number of consecutive dry days (<<mdays>>) within a number of user defined days (<<mcdd>>) (e.g. sum of 4 days > 10mm and maximum 6 consecutive dry days within the next 30 days)

  • sos (th1,th2,nval,NAdays): start of season defined by a threshold amount and distribution of rainfall received in three consecutive dacades (at least th1mm rainfall in first decade and at least th2mm rainfall in following 2 decades. Default values are th1=25mm,th2=20mm). See DETAILS section.

DETAILS

In this case of choosing <<sos>> decades are calculatet starting from start_date defined in the aggregtion. The returned day is the last day of the decade, e.g. if the criterion is met in the second decade, the return value would be 20. The precipitation per decade is calculated by the mean(prec)*10 in order to avoid the influence of missing values. By using the parameter NAdays, the number of allowed missing values per decade can be defined. If the onset criteria are not met the value for the given year is set to NA.

Examples

data(object_st) # load example objects
calc_index(object_st,index="rainy_season_start",aggt="dates",start_days="0000-08-01",end_days="0000-03-01",rs_method="gurgiser")


Climandes/ClimIndVis documentation built on June 9, 2025, 7:09 p.m.