Maximum number of consecutive days with precipitation below a threshold.
This is the ETCCDI CDD index.
Usage
ck_dry_days(precip, dates, threshold = 1, period = "annual")
Arguments
- precip
Numeric vector of daily precipitation (mm).
- dates
Date vector of the same length as precip.
- threshold
Numeric. Dry day threshold in mm (default 1).
- period
Character. Aggregation period: "annual" (default) or
"monthly".
Value
A data frame with columns period, value, index, and unit.
Details
Note: CDD also denotes climpact's cooling degree days, which is
unrelated and is implemented in ck_cooling_degree_days(). In
ck_compute() the name "cdd" resolves here, to consecutive dry days;
"consecutive_dry_days" is accepted as an unambiguous alias.
Examples
dates <- as.Date("2024-01-01") + 0:9
precip <- c(0, 0, 5, 0, 0, 0, 2, 0, 0, 0)
ck_dry_days(precip, dates)
#> period value index unit
#> 1 2024-01-01 3 dry_days days