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Total alkalinity, replicate 1

Total alkalinity replicate 1

µmol/kgkey alkalinity_rep1NERC P01 MDMAP014P06 units KGUMseries alkalinity_rep1

CalCOFI holds 2,084 values of it from 317 sampling events in one dataset, 2008–2015, from the surface to 3,542 m.R Alkalinity is the water’s buffer: with dissolved inorganic carbon it fixes pH and how much carbonate is left for shells, which is what decides whether upwelled water is corrosive.C

2,084
values
0
flagged
2008–2015
years
1
dataset
1–3,542 m
depth
9 of 12
months
CO₂(aq) · HCO₃⁻ · CO₃²⁻Concentration (moles or mass) of acid-neutralising bases per unit mass of the water column.

Measured in 1 dataset
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.

  • 2,084 values · 317 sampling events · 2008–2015 · 1–3,542 m · 29 grid cells · 26 cruises
    series alkalinity_rep1 · source column ta1 replicate no flag at this grain

Explorera depth section vs normaldb-queryERDDAPThis page as JSON R · Python · Parquet

Every way in 8 ways · ERDDAP · Parquet · R · Python · JSON

Read from measurements.json of release v2026.11.05, 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=%22alkalinity_rep1%22
The structure 3 structures
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 Drawn from the rosette, analysed ashore
rosette bottle
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)

no flag at this grain
NCEI accession 0301029 (DIC/alkalinity instruments); Bottle sampling methods on calcofi.org ↗
Why it matters 4 ways to say it · EOV Inorganic carbon
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?

GOOS specification sheet ↗ · quoted, not copied

other ways to say why · 3
  • authored Neither alkalinity nor DIC says much alone; the carbonate system is read from the pair. needs a citation before it can be the pick
  • GOOS asks How is the ocean carbon content changing? source
  • Wikipedia Alkalinity (from Arabic: القلوية, romanized: al-qaly, lit. 'ashes of the saltwort') is the capacity of water to resist acidification. Alkalinity · CC BY-SA 4.0 · rev. 1377364008
The record’s own history no climatology to depart from

Each year against the normal
i

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

Units and range µmol/kg · 0 … 5000 declared · 0 flagged

µmol/kg (umol/kg in metadata/measurement_type.csv) · P06 units KGUM

bounds0 … 5000 µmol/kgobserved2182 … 2435 µmol/kgflagged0baselineclimatology ✓
details
bounds
The registry declares 0 … 5000 µmol/kg for alkalinity_rep1; a value outside it is dropped at the ingest (drop_out_of_bounds()).
observed
Hydrographic Bottle alkalinity_rep1 2182 · median 2244 · 2435 µmol/kg (5th–95th percentile 2217–2317)
flags
Hydrographic Bottle alkalinity_rep1 carries no quality code at the release grain; qual_ok keeps all 2,084.
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.

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.

By depth · by month 1–3,542 m · 9 of 12 months

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.

Cite the release, v2026.11.05

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.