CalCOFI.io CalCOFI.io open data ecosystem
Measurement · Carbonate System · µmol/kg

Dissolved inorganic carbon replicate 1

NERC P01 TCO2MSXXP06 units KGUM umol/kgkey dic_rep1 series dic_rep1
1,999
values
0
flagged
275
sampling events
2008–2015
years
1
dataset
1–3,542 m
depth
Jan · Feb · Mar · Apr · May · Jul · Aug · Oct · Nov
seasons
What

CO₂(aq) · HCO₃⁻ · CO₃²⁻

Concentration of dissolved inorganic carbon per unit mass of the water column. Solute may be expressed in terms of mass or quantity of substance.

Why

How is the ocean carbon content changing?

CalCOFI holds 1,999 values of it from 275 sampling events in one dataset, 2008–2015, from the surface to 3,542 m.R The ocean has taken up a large share of the carbon dioxide people have emitted, and dissolved inorganic carbon is where it sits; with alkalinity it fixes pH and the carbonate that shells are built from.C

other ways to say why · 5
  • authored The ocean sink is one of the terms the global carbon budget is balanced on, and it is measured with exactly this quantity. needs a citation before it can be the pick
  • GOOS asks How is the ocean carbon content changing? source
  • GOOS asks What are rates and impacts of ocean acidification? source
  • calcofi.org CalCOFI samples it for first, the long-term characterization of the inorganic carbon system and its response to changing ocean climate, and second, measurements of pH in the coastal zone in order to monitor the impact of ‘corrosive’ waters on benthic ecosystems in the Southern California Bight. source
  • Wikipedia Dissolved inorganic carbon (DIC) is the sum of the aqueous species of inorganic carbon in a solution. Carbon compounds can be distinguished as either organic or inorganic, and as dissolved or particulate, depending on their composition. Dissolved inorganic carbon · CC BY-SA 4.0 · rev. 1294570528

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 1,999 values · 275 sampling events · 2008–2015 · 1–3,542 m · 29 grid cells · 26 cruises
    series dic_rep1 · source column dic1 · flag column dic_quality_comment replicate

The structure

CO2 carbon dioxide CHEBI:16526 · 44.009 g/mol · component
CHO3− hydrogencarbonate CHEBI:17544 · 61.016 g/mol · component
CO32− carbonate CHEBI:41609 · 60.008 g/mol · component

ChEBI: “A one-carbon compound with formula CO2 in which the carbon is attached to each oxygen atom by a double bond. A colourless, odourless gas under normal conditions, it is produced during respiration by all animals, fungi and microorganisms that depend directly or indirectly on living or decaying plants for food.” · RDKit 2026.03.6 from the ChEBI SMILES (the molfile is vertical), in the page’s ink · CC BY 4.0. ChEBI’s roles are never shown.

How it is measured

Hydrographic Bottle · rosette bottle
Drawn from the rosette, analysed ashore

Samples drawn from the Niskins at selected stations and analysed ashore; total inorganic carbon and alkalinity are measured, from which pH and pCO2 can be calculated, calibrated to the certified reference materials Scripps prepares for the world. (NCEI accession 0301029 (DIC/alkalinity instruments); calcofi.org Bottle sampling methods)

flag dic_quality_comment
NCEI accession 0301029 (DIC/alkalinity instruments); 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

The release builds no climatology for this measurement, so there is no normal to draw a departure from.

Essential Ocean Variable
Inorganic carbon

the GOOS specification sheet for this Essential Ocean Variable lists it, and asks

GOOS asks

  • How is the ocean carbon content changing?
  • What are rates and impacts of ocean acidification?

GOOS specification sheet ↗ · quoted, not copied

Why CalCOFI samples it, in its own words

CalCOFI samples it for first, the long-term characterization of the inorganic carbon system and its response to changing ocean climate, and second, measurements of pH in the coastal zone in order to monitor the impact of ‘corrosive’ waters on benthic ecosystems in the Southern California Bight. calcofi.org ↗

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=%22dic_rep1%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 … 5000 µmol/kgobserved1949 … 2368 µmol/kgflagged0baselineclimatology ✓
details
bounds
The registry declares 0 … 5000 µmol/kg for dic_rep1; a value outside it is dropped at the ingest (drop_out_of_bounds()).
observed
Hydrographic Bottle dic_rep1 1949 · median 2171 · 2368 µmol/kg (5th–95th percentile 1999–2316)
flags
Hydrographic Bottle dic_rep1 carries no quality code at the release grain (its source column is dic_quality_comment); qual_ok keeps all 1,999.
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).

  • Dissolved inorganic carbon dic · Carbonate Chemistry / DIC · 1983–2021 · 4,236 values · P01 TCO2MSXX a replicate of the source's repeated analyses beside a reported mean; the providers have been asked which to publish

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.