https://doi.org/10.6073/pasta/63c4e57f87861db3acaf80d1dec103e1 https://calcofi.io/datasets/cce-lter_iron/ Dissolved iron Katherine Barbeau Scripps Institution of Oceanography (SIO) kbarbeau@ucsd.edu 2026-10-21 eng Dissolved iron (Fe) concentrations from CalCOFI cruises in the southern California Current System, Nov. 2002 - July 2004 (completed). Surface (0 m) samples collected with a pole sampler, analyzed by FeLume flow-injection analysis. The source also carries total iron (no real values) and a shipboard iron-addition bioassay response (Chla response to Fe+, units unconfirmed); neither is released yet. Dissolved Nutrients Phytoplankton Biomass and Diversity CalCOFI Network Iron Nutrients & Chemistry dissolved_iron nmol/L This work is licensed under a Custom terms stated by the provider. https://calcofi.io/datasets/cce-lter_iron/ 29.9–35.1°N, 124.3–117.3°W -124.323 -117.307 35.088 29.85 2002 2004 Never; archived California Current Ecosystem Long Term Ecological Research kbarbeau@ucsd.edu Seawater samples collected primarily from the mixed layer (surface, 0 m) using a pole sampler; some samples collected via a trace metal clean Teflon pump system, with profiles using GO-Flo bottles on synthetic line under ultra-pure filtration protocols. Dissolved iron analyzed by FeLume flow-injection analysis. A subset of samples also carry results from shipboard iron-addition bioassays tracking the chlorophyll-a response. Frequency: selected stations, seasonally. QC flags present: No. Surface samples were collected by pole; no field blanks, replicates or contamination flags are documented, and units ('nM/L' in the file header) and any detection limit are unconfirmed with the provider. Values are published as nmol/L. sample One row per physical sampling event at its native grain (site, tow, net, subsample, cast, bottle, water, filter, underway, transect, sighting, deployment, scan, region pool). An adjacency list: parent_sample_key points at the containing event and root_sample_key at the top of the chain, so counting distinct events at any level is a single GROUP BY. sample_key Sample Key Globally unique event key, namespaced dataset_key:sample_type:id so the same integer id in two datasets — or at two event levels in one dataset — never collides. VARCHAR Globally unique event key, namespaced dataset_key:sample_type:id so the same integer id in two datasets — or at two event levels in one dataset — never collides. sample_type Sample Type Event grain: site, tow, net, subsample, cast, bottle, water (an eDNA water sample), filter (an eDNA water filter), underway, transect (a visual-survey effort segment), sighting, deployment (a sonobuoy), scan (one analysed hour of a recording) or region_pool. VARCHAR Event grain: site, tow, net, subsample, cast, bottle, water (an eDNA water sample), filter (an eDNA water filter), underway, transect (a visual-survey effort segment), sighting, deployment (a sonobuoy), scan (one analysed hour of a recording) or region_pool. parent_sample_key Parent Sample Key The containing event (net → tow → site; bottle → cast; sighting → transect; scan → deployment). NULL at the top of the chain. Flat adjacency list: attributes are not inherited. VARCHAR The containing event (net → tow → site; bottle → cast; sighting → transect; scan → deployment). NULL at the top of the chain. Flat adjacency list: attributes are not inherited. root_sample_key Root Sample Key Top of this event's containment chain; equals sample_key for single-level datasets. Use count(DISTINCT root_sample_key) to count stations/casts irrespective of grain. VARCHAR Top of this event's containment chain; equals sample_key for single-level datasets. Use count(DISTINCT root_sample_key) to count stations/casts irrespective of grain. dataset_key Dataset Key Provenance stamp: provider_dataset. VARCHAR Provenance stamp: provider_dataset. grid_key Grid Key CalCOFI station grid cell. NULL where the dataset has no station assignment (region-pooled phytoplankton). VARCHAR CalCOFI station grid cell. NULL where the dataset has no station assignment (region-pooled phytoplankton). site_key Site Key CalCOFI station natural key as the source records it (line/station, e.g. 090.0 060.0). Present on 13 of the 18 source event tables, so it is carried on the event dimension rather than lost to consolidation; grid_key is the derived grid cell, this is the source's own station id. VARCHAR CalCOFI station natural key as the source records it (line/station, e.g. 090.0 060.0). Present on 13 of the 18 source event tables, so it is carried on the event dimension rather than lost to consolidation; grid_key is the derived grid cell, this is the source's own station id. cruise_key Cruise Key CalCOFI cruise natural key YYYY-MM-NODC. VARCHAR CalCOFI cruise natural key YYYY-MM-NODC. order_occ Order of Occupation Order in which the station was occupied on the cruise. Source spelling varies (order_occ, ord_occ) and CTD stores it as text; normalised to an integer here. INTEGER dimensionless integer latitude Latitude Event latitude (WGS84). DOUBLE degree real longitude Longitude Event longitude (WGS84). DOUBLE degree real datetime Datetime Event start time (UTC). TIMESTAMP YYYY-MM-DDThh:mm:ss depth_min_m Depth Min Shallowest depth sampled by this event. DOUBLE meter real depth_max_m Depth Max Deepest depth sampled by this event; for swfsc_ichthyo tows and nets the maximum possible depth of the net (SWFSC Net.NetDepth, nominal: over a shallower sea floor the net did not reach it). DOUBLE meter real tow_type Tow Type Net gear code where the dataset records one (C1/CB/CV/PV oblique or vertical, MT manta); NULL for gears and datasets without one. Needed to compute gear-appropriate CPUE. VARCHAR Net gear code where the dataset records one (C1/CB/CV/PV oblique or vertical, MT manta); NULL for gears and datasets without one. Needed to compute gear-appropriate CPUE. data_stage Data Stage The source's own processing state for this event: final (post-cruise calibrations applied) or preliminary (not for publication — the source warns that oxygen, nitrate and chlorophyll may change significantly once calibrated). Populated by calcofi_ctd-cast; NULL where the dataset draws no such distinction, which is not a claim that the data are final. VARCHAR The source's own processing state for this event: final (post-cruise calibrations applied) or preliminary (not for publication — the source warns that oxygen, nitrate and chlorophyll may change significantly once calibrated). Populated by calcofi_ctd-cast; NULL where the dataset draws no such distinction, which is not a claim that the data are final. geom Geometry Point geometry minted from longitude/latitude (OGC:CRS84). GEOMETRY('EPSG:4326') Point geometry minted from longitude/latitude (OGC:CRS84). source_uuid Source Uuid Source Uuid UUID Source Uuid hex7 H3 Cell (res 7) One UBIGINT H3 cell at resolution 7: the parent of the resolution-10 cell of this event's own latitude / longitude (not the resolution-7 cell the position falls in), defined exactly as obs_bio.hex7 / obs_env.hex7; NULL without a finite position. Lets a per-sample value in sample_measurement be drawn in hexagons. An observation carries its own position, so a CTD scan can sit in another cell than its cast. UBIGINT dimensionless whole seafloor_depth_m seafloor_depth_m DOUBLE dimensionless real station_uuid station_uuid UUID station_uuid station_uuid_method station_uuid_method VARCHAR station_uuid_method obs The occurrence-headline long table: one scalar measurement per row, environmental (realm = 'env') and biological (realm = 'bio') together. Biological taxon is the global taxon_key; sub-occurrence detail (length/stage bins, behavior) lives in obs_attribute, and event-level effort in sample_measurement. data_0.parquet 6806 2351bd9d17c4c409f5f90b942521e4f9e9041a50c8142a729cfbefd5ecbf110a Apache Parquet https://storage.googleapis.com/calcofi-db/ducklake/tables/obs/dataset_key=cce-lter_iron/de1ec356e734ebeca9b5eb9d/data_0.parquet obs_id Observation ID Surrogate key, renumbered globally when the release concatenates the per-dataset shards. BIGINT dimensionless integer realm Realm env for physical/chemical measurements, bio for organism observations. VARCHAR env for physical/chemical measurements, bio for organism observations. dataset_key Dataset Key Provenance stamp: provider_dataset. VARCHAR Provenance stamp: provider_dataset. sample_key Sample Key The sampling event this observation came from; joins sample. VARCHAR The sampling event this observation came from; joins sample. grid_key Grid Key CalCOFI station grid cell, denormalized from sample so rollups need no join. NULL for region-pooled data. VARCHAR CalCOFI station grid cell, denormalized from sample so rollups need no join. NULL for region-pooled data. cruise_key Cruise Key Cruise, denormalized from sample so rollups need no join. VARCHAR Cruise, denormalized from sample so rollups need no join. latitude Latitude Observation latitude (WGS84). DOUBLE degree real longitude Longitude Observation longitude (WGS84). DOUBLE degree real datetime Datetime Observation time (UTC). NULL for region-pooled data with no event time. TIMESTAMP YYYY-MM-DDThh:mm:ss depth_min_m Depth Min Shallowest depth this observation represents. DOUBLE meter real depth_max_m Depth Max Deepest depth this observation represents; equal to depth_min_m for point measurements (bottle, CTD scan). DOUBLE meter real taxon_key Taxon Key Global taxon key, worms:<AphiaID> or itis:<TSN> for birds. NULL for env rows. Joins taxon. VARCHAR Global taxon key, worms:<AphiaID> or itis:<TSN> for birds. NULL for env rows. Joins taxon. life_stage Life Stage Life stage where the source resolves one (larva, adult, juvenile, egg, phyllosoma). VARCHAR Life stage where the source resolves one (larva, adult, juvenile, egg, phyllosoma). measurement_type Measurement Type Measured quantity; joins the measurement_type vocabulary. VARCHAR Measured quantity; joins the measurement_type vocabulary. measurement_value Measurement Value The measured value, in the units measurement_type declares. DOUBLE dimensionless real measurement_qual Measurement Qualifier Source quality flag, verbatim. VARCHAR Source quality flag, verbatim. measurement_prec Measurement Precision Source-reported precision where available. DOUBLE dimensionless real hex_id Hex ID H3 cell at resolution 10, stored as UBIGINT. Aggregate coarser at query time with h3_cell_to_parent(hex_id, res) — there is no per-resolution column ladder. UBIGINT dimensionless whole measurement_type measurement_type Measurement Type Measurement Type VARCHAR Measurement Type description Description Description VARCHAR Description units Units Units VARCHAR Units valid_min Valid Min Valid Min DOUBLE dimensionless real valid_max Valid Max Valid Max DOUBLE dimensionless real valid_depth_min_m Valid Depth Min M Valid Depth Min M DOUBLE dimensionless real valid_depth_max_m Valid Depth Max M Valid Depth Max M DOUBLE dimensionless real derivation Derivation Derivation VARCHAR Derivation is_canonical Is Canonical Is Canonical BOOLEAN Is Canonical _source_column Source Column Source Column VARCHAR Source Column _source_table Source Table Source Table VARCHAR Source Table _source_datasets Source Datasets Source Datasets VARCHAR Source Datasets _qual_column Qual Column Qual Column VARCHAR Qual Column _prec_column Prec Column Prec Column VARCHAR Prec Column grain Grain Grain VARCHAR Grain denominator Denominator Denominator VARCHAR Denominator category Category Category VARCHAR Category variable Variable Variable VARCHAR Variable nerc_p01 Nerc P01 Nerc P01 VARCHAR Nerc P01 units_nerc_p06 Units Nerc P06 Units Nerc P06 VARCHAR Units Nerc P06 provider Provider Provider VARCHAR Provider dataset Dataset Dataset VARCHAR Dataset California Current Ecosystem LTER, CalCOFI - Scripps Institution of Oceanography, and K. Barbeau. 2017. Measurements of dissolved inorganic concentrations of nutrient iron and of iron limitation at selected stations and depths from CalCOFI cruises in the California Current System, Nov. 2002 - July 2004 (completed) ver 3. Environmental Data Initiative. https://doi.org/10.6073/pasta/63c4e57f87861db3acaf80d1dec103e1. cce-lter_iron https://calcofi.io/datasets/cce-lter_iron/ v2026.10.21 CalCOFI (2026). CalCOFI Integrated Database, release v2026.10.21 [Data set]. Scripps Institution of Oceanography, NOAA Fisheries, and California Department of Fish and Wildlife. https://calcofi.io/db-schema/?v=v2026.10.21 2026-10-21