Silicate concentration
- 381,685
- values
- 232
- flagged
i
232 of these 381,685 values (under 0.1 %) 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). - 15,181
- sampling events
- 1959–2021
- years
- 1
- dataset
- 0–5,351 m
- depth
- every month
- seasons
O4Si4− · silicate(4−) · 92.082 g/mol · CHEBI:29241
Concentration of silicate per unit volume of the water column. Silicate may be expressed in terms of mass or quantity of substance.
Seal Analytical continuous-flow AutoAnalyzer 3 (AA3)
660 nm
Bottle sampling methods on calcofi.org ↗Is the biomass of the ocean changing?
CalCOFI holds 381,685 values of it from 15,181 sampling events in one dataset, 1959–2021, from the surface to 5,351 m. At 10–50 m it has risen 0.00 per decade since 1984.R Diatoms build glass shells, so silicate is the nutrient that decides whether a bloom is made of them; off Southern California it has been rising in the upper pycnocline and falling in the lower one.C
other ways to say why · 3
- When silicate runs out before nitrate does, the bloom shifts away from diatoms and toward cells that sink more slowly and feed a different food web. needs a citation before it can be the pick
- GOOS asks Is the biomass of the ocean changing? source
- Wikipedia In chemistry, a silicic acid is any chemical compound containing the element silicon attached to oxide and hydroxyl groups, with the general formula [H2xSiOx+2]n or, equivalently, [SiOx(OH)4−2x]n. Orthosilicic acid is a representative example. Silicic acid · CC BY-SA 4.0 · rev. 1357664652
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
silicate· source columnsi_o3u_m· flag columnsi_o3qu232 flagged
The structure
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
Armstrong (1967): acidic ammonium molybdate forms silicomolybdic acid, reduced by stannous chloride to a blue compound (tartaric acid suppresses phosphate interference), read in a 10 mm flow cell. (calcofi.org Bottle sampling methods)
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.
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: 1,813 values at 1000–2000 m, 1,093 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: 1,813 values at 1000–2000 m, 1,093 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
- Is the biomass of the ocean changing?
GOOS specification sheet ↗ · quoted, not copied
The record
Ways in i
Read from measurements.json of release
v2026.10.05, 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-queryi
Read from measurements.json of release v2026.10.05, 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.
SELECT * FROM read_json('…/v2026.10.05/catalog.json')
-- objects[] WHERE table = 'obs_env'
-- AND partition_value = 'silicate'library(calcofi4r)
con <- cc_get_db() # the promoted release
tbl(con, "obs_env") |> filter(measurement_type %in% c("silicate"))import calcofi4py as cc
con = cc.cc_get_db()
con.sql("SELECT * FROM obs_env WHERE measurement_type IN ('silicate')").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
0 … 300 µmol/Lforsilicate; a value outside it is dropped at the ingest (drop_out_of_bounds()). - observed
- Hydrographic Bottle
silicate0 · median 18 · 196 µmol/L (5th–95th percentile 1.46–78.4) - flags
- Hydrographic Bottle
silicatesi_o3quon 233 of 381,685 rows:41 ·8232; qual_ok keeps 381,453. 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 × grid cell × calendar 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).
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).
- Bottle silicate btl_silicate · CTD Cast Files · 1993–2026 · 144,407 values · P01 SLCAZZXX 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 — Hydrographic Bottle. The Explorer's Share → Cite writes it for the view you make.