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Measurement · Physical Oceanography · m

Reported depth from pressure (pre-QC)

NERC P01 ADEPZZ01P06 units ULAA mkey r_depth series r_depth
895,370
values
0
flagged
35,644
sampling events
1949–2021
years
1
dataset
0–5,351 m
depth
every month
seasons
What

The distance of a sensor or sampling point below the sea surface

How
rosette bottle

Pressure-derived depth

CTD FAQ circa 2020 on calcofi.org ↗

CalCOFI holds 895,370 values of it from 35,644 sampling events in one dataset, 1949–2021, from the surface to 5,351 m. At 10–50 m it has fallen 0.11 per decade since 1984.R Pressure is how a CTD knows where it is, and depth is where the story is: off Southern California oxygen, nitrate and phosphate have changed at different rates in each layer.C

other ways to say why · 2
  • authored Every profile in the record is placed in the water column by its pressure, so a depth error moves a value into the wrong layer rather than losing it. needs a citation before it can be the pick
  • Wikipedia Pressure is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure is the pressure relative to the ambient pressure. Pressure · CC BY-SA 4.0 · rev. 1378601778

The measurement

Measured in
i

One row per series, one cell per year, darker with more values — the same strip the front door draws per dataset and a species page draws per taxon. Each row is one dataset's own measurement_type; the label is written once, in the title above.

  • Hydrographic Bottle 895,370 values · 35,644 sampling events · 1949–2021 · 0–5,351 m · 222 grid cells · 657 cruises
    series r_depth · source column r_depth reported · pre-QC no flag at this grain

How it is measured

Hydrographic Bottle · rosette bottle
Pressure-derived depth

reported depth computed from the reversing-thermometer cast pressure (pre-QC) (calcofi.org CTD FAQ circa 2020)

no flag at this grain
CTD FAQ circa 2020 on calcofi.org ↗

Why it matters

The familiar scale
i

Bars are each series' 5th–95th percentile, the line its minimum to maximum, the ring its median; the marks are metadata/measurement_scale.csv's, each hovering to its own source.

The record’s own history
i

Deeper than the climatology reaches: 4,547 values at 2000+ m have no normal to depart from, because the release’s climatology stops at its deepest built bin. Carrying it to the bottom is one argument of build_climatology() and puts these bands on the page too.

The record

Ways in
i

Read from measurements.json of release v2026.10.14, written at release by calcofi4db::build_measurements_catalog() beside taxa.json. The catalog's index is /measurements/; the JSON-LD on this page is a schema.org/DefinedTerm in the NERC P01 term set with a PropertyValue per series.

ExplorerExplorer · a depth section vs normaldb-query
ERDDAP · Hydrographic BottleCalCOFI's own server, the Hydrographic Bottle table constrained to this series
https://erddap.calcofi.io/erddap/tabledap/calcofi_bottle.html?&measurement_type=%22r_depth%22

By depth
i

Values per depth band at the release grain, one thin bar per series. The bands are the record's own (0-10 … 2000+ m).

By month
i

Values per calendar month, one row per series: CalCOFI's quarterly cruises show as peaks in the months the ships sail.

Range & quality

bounds0 … 11,000 mobserved0 … 5458 mflagged0baselineclimatology ✓
details
bounds
The registry declares 0 … 11,000 m for r_depth; a value outside it is dropped at the ingest (drop_out_of_bounds()).
observed
Hydrographic Bottle r_depth 0 · median 126 · 5458 m (5th–95th percentile 2–788)
flags
Hydrographic Bottle r_depth carries no quality code at the release grain; qual_ok keeps all 895,370.
baseline
A monthly climatology exists for this measurement (the release's climatology table: 1993–2013, dataset × station × the cruise's month × 10 m bin), so the Explorer can draw anomalies against it rather than values.
derivation
reported value interpolated to standard depth (pre-QC, decodr); carries no quality code by design; not an input for further interpolation

Related measurements
i

The same quantity from another platform or another kind of sample, each its own page and never merged into this one: a dataset's own bottle samples would count that dataset twice, an underway intake is not a cast, and a replicate is not a mean. The reason is the record's (related[].why).

  • Bottle trip depth btl_depth · CTD Cast Files · 1993–2026 · 156,745 values · P01 ADEPZZ01 the same quantity from the CTD files' own bottle samples — plausibly the same physical bottles, so merging them would count the bottle dataset twice

Cite

Cite the release; each dataset's own citation, licence and DOI are on its page — Hydrographic Bottle. The Explorer's Share → Cite writes it for the view you make.