Temperature
Water temperature (QC'd)
- 1,575,559
- values
- 575
- flagged
i
575 of these 1,575,559 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). Thetemperature_aveseries from CTD Cast Files is an average of two sensors, rebuilt with any sensor its provider flags questionable or bad left out, so it carries no flag of its own. - 45,019
- sampling events
- 1949–2026
- years
- 2
- datasets
- 0–5,351 m
- depth
- every month
- seasons
The degree of hotness of the water column expressed against a standard scale. Includes both IPTS-68 and ITS-90 scales.
Reversing thermometers on the bottles, then the CTD
CTD FAQ circa 2020 on calcofi.org ↗EOV Subsurface temperature
CalCOFI holds 1,575,559 values of it from 45,019 sampling events in 2 datasets, 1949–2026, from the surface to 5,351 m. At 200–500 m it has risen 0.06 per decade since 1984.R Temperature sets the water’s density, and so the layering that decides whether deep nutrients reach the sunlit surface; off California the warm years are El Niño years and marine heatwaves.C
other ways to say why · 3
- A warm year off California is usually a lean one: warmer, more layered water brings fewer nutrients up, and the plankton the rest of the food web eats decline. needs a citation before it can be the pick
- Wikipedia Marine heatwave source
- Wikipedia Sea surface temperature is the temperature of ocean water close to the surface. The exact meaning of surface varies in the literature and in practice. Sea surface temperature · CC BY-SA 4.0 · rev. 1374459881
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
temperature· source columnt_deg_c· flag columnt_qual575 flagged -
series
temperature_ave· source columntemp_avesensor mean no flag at this grainAverage temperature
How it is measured
Originally reversing thermometers on the 20 Nansen/Niskin bottles, read on deck after about 45 minutes of equilibration; the CTD arrived in the early 1990s under protocols built to keep its readings comparable to the bottle-thermometer series. (calcofi.org CTD FAQ circa 2020)
CTD FAQ circa 2020 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: 24,154 values at 1000–2000 m, 7,758 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: 24,154 values at 1000–2000 m, 7,758 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
The record
Ways in i
Read from measurements.json of release
v2026.09.11, 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 v2026.09.11, 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('…/v2026.09.11/catalog.json')
-- objects[] WHERE table = 'obs_env'
-- AND partition_value = 'temperature'
-- | 'temperature_ave'library(calcofi4r)
con <- cc_get_db() # the promoted release
tbl(con, "obs_env") |> filter(measurement_type %in% c("temperature", "temperature_ave"))import calcofi4py as cc
con = cc.cc_get_db()
con.sql("SELECT * FROM obs_env WHERE measurement_type IN ('temperature', 'temperature_ave')").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
-2 … 40 °Cfortemperature · temperature_ave; a value outside it is dropped at the ingest (drop_out_of_bounds()). - observed
- Hydrographic Bottle
temperature1.44 · median 10.07 · 31.14 °C (5th–95th percentile 4.7–18.2)
CTD Cast Filestemperature_ave1.508 · median 8.994 · 36.22 °C (5th–95th percentile 5.817–16.5) - flags
- Hydrographic Bottle
temperaturet_qualon 13,047 of 884,400 rows:0170 ·1118 ·2135 ·3104 ·453 ·5129 ·611,756 ·77 ·8575; qual_ok keeps 883,825. The codes are this dataset's own vocabulary, uninterpreted.
CTD Cast Filestemperature_avecarries no quality code at the release grain; qual_ok keeps all 691,159. - 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 temperature btl_temperature · CTD Cast Files · 1993–2025 · 141,771 values · P01 TEMPPR01 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, CTD Cast Files. The Explorer's Share → Cite writes it for the view you make.