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Measurement · Physical Oceanography · 10⁻⁸ m³/kg

Specific volume anomaly

P06 units UMKS 10^-8 m3/kgkey specific_volume_anomaly series specific_volume_anomaly
536,337
values
0
flagged
7,438
sampling events
1993–2026
years
1
dataset
1–3,541 m
depth
Jan · Feb · Mar · Apr · May · Jun · Jul · Aug · Sep · Oct · Nov
seasons
What
How
CTD sensor

Computed from the cast profile

CalCOFI holds 536,337 values of it from 7,438 sampling events in one dataset, 1993–2026, from the surface to 3,541 m. At 200–500 m it has risen 0.14 per decade since 1993.R Dynamic height is the tilt of the sea surface the currents balance: mapped across the CalCOFI grid it is how the California Current and the Undercurrent were first described season by season.C

other ways to say why · 2
  • authored It is computed from temperature and salinity down a cast, so it carries whatever those two series carry. needs a citation before it can be the pick
  • Wikipedia A geostrophic current is an oceanic current in which the pressure gradient force is balanced by the Coriolis effect. The direction of geostrophic flow is parallel to the isobars, with the high pressure to the right of the flow in the Northern Hemisphere, and the high pressure to the left in the Southern Hemisphere. Geostrophic current · CC BY-SA 4.0 · rev. 1344173703

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 536,337 values · 7,438 sampling events · 1993–2026 · 1–3,541 m · 113 grid cells · 107 cruises
    series specific_volume_anomaly · source column sva · flag column svaq no bound declared range suspect · no bound no P01 concept

How it is measured

CTD Cast Files · CTD sensor
Computed from the cast profile

A derived hydrographic quantity computed from the cast profile, not sensed directly. (the record's own derivation (measurement_type.csv))

flag svaq

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: 1,777 values at 1000–2000 m, 1,085 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 · 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=%22specific_volume_anomaly%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

boundsno bound declaredobserved−63,921 … 5723 10⁻⁸ m³/kgflagged0baselineclimatology ✓
details
bounds
No physical bound is declared for this series in metadata/measurement_type.csv, so nothing is enforced at the ingest and the range below is simply what the release carries.
observed
CTD Cast Files specific_volume_anomaly −63,921 · median 171 · 5723 10⁻⁸ m³/kg (5th–95th percentile 114.7–360.3)
flags
CTD Cast Files specific_volume_anomaly carries no quality code at the release grain (its source column is svaq); qual_ok keeps all 536,337.
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.

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.