Depth-integrate one CTD cast's profile — ctd

Trapezoidal integral of value from the surface to z_max (default 200 m) or to the deepest good sample if shallower, which is recorded (CalCOFI/workflows#102; Rasmus Swalethorp, 2026-09-16: integrated chlorophyll "is just summing up all the 1 m bins" — on 1 m bins the trapezoid and the sum differ only by half the two end bins). The shallowest good sample is carried up to the surface when it is no deeper than z_top_max (default 5 m); a cast that starts deeper is NA (status no_surface), so a missing surface is never silently skipped. Flagged samples are dropped first. For chlorophyll-a in mg m^-3 the result is mg m^-2.

Usage

ctd_integrate(depth, value, qual = NA, z_max = 200, z_top_max = 5)

Arguments

depth: depth (m), one cast.
value: the quantity per unit volume.
qual: quality codes of value (NA = good).
z_max: integration floor (m), default 200.
z_top_max: deepest acceptable first sample (m), default 5.

Value

one-row tibble: integrated, depth_reached_m, status (ok, shallow, no_surface, no_data), z_max.

Examples

ctd_integrate(0:300, rep(1, 301))   # 200 over 0-200 m
#> # A tibble: 1 × 4
#>   integrated depth_reached_m status z_max
#>        <dbl>           <dbl> <chr>  <dbl>
#> 1        200             200 ok       200