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Measurement · Productivity & Pigments · µg/L

Bottle phaeopigment

NERC P01 PHAEZZXXP06 units UGPL ug/Lkey btl_phaeopigment series btl_phaeopigment
113,138
values
0
flagged
9,089
sampling events
1993–2026
years
1
dataset
1–1,122 m
depth
Jan · Feb · Mar · Apr · May · Jun · Jul · Aug · Sep · Oct · Nov
seasons
What

Filtration and analysis protocols unspecified.

How
rosette bottle

Filter, 90% acetone extraction, benchtop fluorometer (bottle value carried on the CTD cast file)

Bottle sampling methods on calcofi.org ↗

EOV Phytoplankton biomass and diversity

CalCOFI holds 113,138 values of it from 9,089 sampling events in one dataset, 1993–2026, from the surface to 1,122 m. At 10–50 m it has fallen 0.02 per decade since 1993.R Phaeopigment is chlorophyll after something has eaten it or it has died, so the ratio of the two is a reading of how fast the grazers are working through the bloom.C

other ways to say why · 2
  • authored It is also the reason chlorophyll is read twice, before and after acid: the acid makes the same change in the tube that grazing makes in the sea. needs a citation before it can be the pick
  • Wikipedia Pheophytin or phaeophytin is a chemical compound that serves as the first electron carrier intermediate in the electron transfer pathway of Photosystem II in plants, and the type II photosynthetic reaction center found in purple bacteria. In both PS II and RC P870, light drives electrons from the reaction center through pheophytin, which then passes the electrons to a quinone (QA) in RC P870 and RC P680. Pheophytin · CC BY-SA 4.0 · rev. 1373850179

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.

  • CTD Cast Files 113,138 values · 9,089 sampling events · 1993–2026 · 1–1,122 m · 109 grid cells · 128 cruises
    series btl_phaeopigment · source column phaeo no flag at this grain

The structure

C55H74N4O5 pheophytin a CHEBI:44898 · 871.220 g/mol · one_of

RDKit 2026.03.6 from the ChEBI molfile, in the page’s ink · CC BY 4.0. ChEBI’s roles are never shown.

How it is measured

CTD Cast Files · rosette bottle
Filter, 90% acetone extraction, benchtop fluorometer (bottle value carried on the CTD cast file)

A known volume filtered onto a GF/F filter, cold-extracted in 90% acetone for 24-48 hours and read on a fluorometer; the extract is then acidified, which strips the magnesium and turns chlorophyll into phaeopigment, and read again (Yentsch & Menzel 1963; Holm-Hansen et al. 1965; Lorenzen 1967). (calcofi.org Bottle sampling methods)

no flag at this grain
Bottle sampling methods 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: 32 values at 500–1000 m, 24 values at 1000–2000 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.

Essential Ocean Variable
Phytoplankton biomass and diversity

the GOOS specification sheet for this Essential Ocean Variable lists it

GOOS specification sheet ↗

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 · CTD Cast FilesCalCOFI's own server, the CTD Cast Files table constrained to this series
https://erddap.calcofi.io/erddap/tabledap/calcofi_ctd-cast.html?&measurement_type=%22btl_phaeopigment%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

bounds-5 … 100 µg/Lobserved-1.722 … 12.35 µg/Lflagged0baselineclimatology ✓
details
bounds
The registry declares -5 … 100 µg/L for btl_phaeopigment; a value outside it is dropped at the ingest (drop_out_of_bounds()).
observed
CTD Cast Files btl_phaeopigment -1.722 · median 0.121 · 12.35 µg/L (5th–95th percentile 0.02–0.649)
flags
CTD Cast Files btl_phaeopigment carries no quality code at the release grain; qual_ok keeps all 113,138.
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.

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).

  • Phaeopigment measured fluorometrically phaeopigment · Hydrographic Bottle · 1973–2021 · 245,665 values · P01 PHAEZZXX 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 — CTD Cast Files. The Explorer's Share → Cite writes it for the view you make.