ET-SCI heatwave family index. Annual count of distinct heatwave events, where a heatwave is a span of at least three consecutive days with daily Tmax above the 90th percentile of the calendar-day distribution from a reference period (default 1961 to 1990).
Arguments
- tmax
Numeric vector of daily maximum temperatures (degrees C).
- dates
Date vector of the same length as
tmax. Must contain data covering the reference period.- ref_start, ref_end
Integer. Reference period boundary years (inclusive). Defaults to 1961 and 1990.
- min_spell
Integer. Minimum spell length in days (default 3, the ET-SCI standard).
Details
Single-threshold definition (TX-only). For the dual-threshold
Perkins-Alexander variant (TX and TN both above 90th percentile) see
climpact.
Examples
set.seed(1)
dates <- seq(as.Date("1961-01-01"), as.Date("1991-12-31"), by = "day")
tmax <- 15 + 10 * sin(2 * pi * as.integer(format(dates, "%j")) / 365) +
rnorm(length(dates))
tail(ck_hwn(tmax, dates))
#> period value index unit
#> 26 1986-01-01 0 hwn events
#> 27 1987-01-01 1 hwn events
#> 28 1988-01-01 0 hwn events
#> 29 1989-01-01 0 hwn events
#> 30 1990-01-01 0 hwn events
#> 31 1991-01-01 1 hwn events