Calculates the proportion of rainfall above the refrerence_rainfall value. Usually the reference corresponds to the 95th percentile of a climate normal/reference period. The proportion is often calculated in an annual basis and is a measure of the proportion of annual total rain that falls in intense events. This measure provides information about the importance of intense rainfall events for total annual rainfall.
precipitation_above_reference( precipitation, reference_precipitation, wet_day_threshold = 1 )
| precipitation | vector with rainfall values |
|---|---|
| reference_precipitation | reference value of precipitation |
| wet_day_threshold | Numeric. Amount of precipitation at which the day is considered a wet day. Defaults to 1. |
a value between 0 and 1
Other rainfall functions:
get_reference_precipitation()
library(dplyr) # Simulate one measurement of rain per day for 10 years rainfall <- rlnorm(10*365) years <- rep(2001:2010, each = 365) rain_data <- tibble(rainfall = rainfall, year = years) # We chose a climate normal climate_normal <- c(2001, 2005) rain_data %>% # calculate reference rainfall mutate(ref = get_reference_precipitation(rainfall, year, climate_normal, percentile = 95L)) %>% # calculate prorportion of rainfall above reference group_by(year) %>% summarise(prop_above = precipitation_above_reference(rainfall, ref))#> # A tibble: 10 × 2 #> year prop_above #> <int> <dbl> #> 1 2001 0.253 #> 2 2002 0.196 #> 3 2003 0.187 #> 4 2004 0.156 #> 5 2005 0.157 #> 6 2006 0.171 #> 7 2007 0.333 #> 8 2008 0.183 #> 9 2009 0.246 #> 10 2010 0.0986