Oxygen percent saturation
- 690,745
- values
- 2,660
- flagged
i
2,660 of these 690,745 values (0.4 %) are flagged by their provider as questionable or bad. The Explorer, the climatology and its anomalies leave them out; do the same when you read the data yourself (cc_qual_ok_sql()in calcofi4r,qual_ok_sql()in calcofi4py). - 26,995
- sampling events
- 1949–2021
- years
- 1
- dataset
- 0–5,351 m
- depth
- every month
- seasons
Computed (algorithm/data source unspecified)
Computed from bottle dissolved oxygen, temperature and salinity
How large are the ocean’s “dead zones” and how fast are they changing?
CalCOFI holds 690,745 values of it from 26,995 sampling events in one dataset, 1949–2021, from the surface to 5,351 m. At 200–500 m it has fallen 2.18 per decade since 1984.R Below the mixed layer off Southern California oxygen has fallen since the 1980s and the hypoxic boundary has risen toward the shelf, squeezing the habitat of fish and invertebrates.C
other ways to say why · 7
- Saturation says whether the water holds more or less oxygen than the air would give it at that temperature, so it separates warming from breathing. needs a citation before it can be the pick
- Oxygen is the balance of what the ocean takes in at the surface and what animals and bacteria use below; a warmer ocean holds less and mixes less, so it is losing oxygen. needs a citation before it can be the pick
- Warming thins the oxygen the surface layer can hold, and the upper ocean has been losing it for decades across the North Pacific, not only here. needs a citation before it can be the pick
- GOOS asks How large are the ocean’s “dead zones” and how fast are they changing? source
- GOOS asks Is the biomass of the ocean changing? source
- Wikipedia Hypoxia (environmental) source
- Wikipedia Ocean deoxygenation is the reduction of the oxygen content in different parts of the ocean due to human activities. There are two areas where this occurs. Ocean deoxygenation · CC BY-SA 4.0 · rev. 1354922617
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.
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.
-
series
oxygen_saturation· source columno2sat· flag columno2satq2,660 flagged · 0.4 %
How it is measured
Percent saturation computed from the bottle Winkler oxygen against the solubility at that temperature and salinity. (the record's own derivation (measurement_type.csv))
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.
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: 13,400 values at 1000–2000 m, 3,521 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.
i
Deeper than the climatology reaches: 13,400 values at 1000–2000 m, 3,521 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 GOOS specification sheet for this Essential Ocean Variable lists it, and asks
GOOS asks
- How large are the ocean’s “dead zones” and how fast are they changing?
- Is the biomass of the ocean changing?
GOOS specification sheet ↗ · quoted, not copied
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-queryi
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.
SELECT * FROM read_json('…/v2026.10.14/catalog.json')
-- objects[] WHERE table = 'obs_env'
-- AND partition_value = 'oxygen_saturation'library(calcofi4r)
con <- cc_get_db() # the promoted release
tbl(con, "obs_env") |> filter(measurement_type %in% c("oxygen_saturation"))import calcofi4py as cc
con = cc.cc_get_db()
con.sql("SELECT * FROM obs_env WHERE measurement_type IN ('oxygen_saturation')").df()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).
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.
i
Values per calendar month, one row per series: CalCOFI's quarterly cruises show as peaks in the months the ships sail.
Range & quality
details
- bounds
- The registry declares
-1 … 250 %foroxygen_saturation; a value outside it is dropped at the ingest (drop_out_of_bounds()). - observed
- Hydrographic Bottle
oxygen_saturation-0.1 · median 54.6 · 214.1 % (5th–95th percentile 5.2–105.2) - flags
- Hydrographic Bottle
oxygen_saturationo2satqon 28,127 of 690,745 rows:21,859 ·623,608 ·82,657 ·93; qual_ok keeps 688,085. The codes are this dataset's own vocabulary, uninterpreted. - 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 — Hydrographic Bottle. The Explorer's Share → Cite writes it for the view you make.