spei: Calculate Standardized Precipitation Evapotranspiration Index...

In flogrc/piflow: Precipitation and discharge analysis tools with zoo vector

Description

Calculate SPEI and the drought specifications with the length, the drought type and the intensity

Usage

spei(prec_data, evapo_data, time_step = 12,
  distribution = "log-Logistic")

Arguments

prec_data	[zoo] rainfall monthly data in zoo class with date in %Y-%m-%d
evapo_data	[zoo] evapotranspiration monthly data in zoo class with date in %Y-%m-%d
time_step	[numeric] by default = 12, time step to sum monthly data (1, 3, 6, 9, 12, 24 and 48)
distribution	[character] distribution of data (log_Logistic, gamma, grev, genlog, normal)

Value

list that contains

spei [zoo] zoo with the spei values with date in %Y-%m-%d

drought_type [zoo] zoo with the type of the period for each month

drought_number [data.frame] dataframe with the number of different period by type

• Extwet (spei > 2)
  

• Verywet (1.99 > spei > 1.5)
  

• Wet (1.49 > spei > 1)
  

• Normal (0.99 > spei > -0.99)
  

• Dry (-1 > spei > -1.49)
  

• VeryDry (-1.5 > spei > -1.99)
  

• ExtDry (-2 > spei)

Author(s)

Florine Garcia ([e-mail])

Pierre L'Hermite ([e-mail])

References

Vincente-Serrano, S.M. et al, (2010) A multiscalar drought index sensitive to global warming: the standardized precipitation evapotranspiration index. Journal of Climate, 23 https://www.researchgate.net/profile/Sergio_Vicente-Serrano/publication/262012840_A_Multiscalar_Drought_Index_Sensitive_to_Global_Warming_The_Standardized_Precipitation_Evapotranspiration_Index/links/540c6b1d0cf2f2b29a377f27/A-Multiscalar-Drought-Index-Sensitive-to-Global-Warming-The-Standardized-Precipitation-Evapotranspiration-Index.pdf

See Also

plot_trend: plot the index

Examples

How to use function

flogrc/piflow documentation built on May 24, 2019, 7:34 a.m.