SJVAir brings together data from community sensor networks, regulatory agencies, and national research programs to provide a more complete picture of air quality in the San Joaquin Valley. By integrating multiple sources, we combine the broad reach of low-cost monitors with the reliability of reference-grade systems and emerging datasets from satellites and models.
Data from ground-level sensors, both community-deployed and regulatory-grade, providing real-time measurements of PM2.5, ozone, and other key pollutants across the San Joaquin Valley.
AirGradient is an open-source air quality platform that provides both ready-to-use monitors and DIY kits for community scientists. Their commitment to transparency and open data has made them a valuable collaborator in environmental monitoring. In SJVAir, we include all publicly accessible AirGradient monitors in the San Joaquin Valley, with an emphasis on tested and verified units to ensure data quality.
PurpleAir is one of the largest community air quality sensor networks in the world. Their low-cost monitors are widely deployed by residents, schools, and community groups, creating dense coverage across neighborhoods. In SJVAir, we incorporate every publicly accessible PurpleAir monitor in the San Joaquin Valley, alongside a subset of units that we independently test and verify for reliability.
AirNow is the official U.S. platform for air quality information, operated through a partnership of the Environmental Protection Agency, NOAA, NASA, the National Park Service, the CDC, and state, tribal, and local agencies. It serves as the central hub for regulatory-grade monitoring data, providing the public with reliable and standardized air quality information nationwide.
AQview is the California Air Resources Board's (CARB) data platform for AB 617 communities, providing regulatory-grade PM2.5 measurements in areas most impacted by air pollution. Because AQview does not offer a public API, SJVAir is one of the only external platforms to integrate and display this data outside of CARB's own system.
The San Joaquin Valley Air Pollution Control District is the regulatory agency for the Valley's air basin. Each day it issues an air quality forecast for every part of the basin, by county and by zone. SJVAir ingests these forecasts and shows each one for the area it covers, deriving the zones that do not follow county lines — the Valley portions of Kern and Tulare counties and the Sequoia National Park and Forest zone — from the District's own forecast map.
Satellite observations and atmospheric models that track wildfire smoke, pollution, and regional air quality trends, helping to fill gaps between ground-level measurements.
The NOAA Hazard Mapping System (HMS) Fire and Smoke product provides daily maps of active fires and smoke plumes across North America. Using observations from the GOES geostationary satellites, HMS offers near real-time information on smoke extent and movement, helping communities understand wildfire impacts on local air quality.
Tropospheric Emissions: Monitoring of Pollution (TEMPO) is a NASA mission operated in collaboration with the Smithsonian Astrophysical Observatory. From geostationary orbit, TEMPO measures pollutants such as ozone, nitrogen dioxide, and formaldehyde across North America, providing hourly observations that offer unprecedented insight into air quality at regional and local scales.
Ground-based weather station data that adds local temperature, wind, humidity, and other atmospheric context alongside our air quality measurements across the San Joaquin Valley.
The California Irrigation Management Information System (CIMIS) is a network of automated weather stations operated by the California Department of Water Resources (DWR). Originally built to support agricultural irrigation scheduling, CIMIS stations also report hourly weather data — temperature, humidity, wind speed and direction, solar radiation, and precipitation — which SJVAir uses to add local weather context alongside air quality measurements across the San Joaquin Valley.
The National Weather Service, part of NOAA, publishes forecasts, current conditions, and observations from its network of weather stations through a free public API at weather.gov. SJVAir's map uses it for the temperature shown alongside air quality readings, and we plan to bring its station observations into our own data pipeline alongside CIMIS.
CalHeatScore is California's heat-risk forecasting tool, developed by the Office of Environmental Health Hazard Assessment at CalEPA with the Department of Insurance and the Department of Public Health. It rates each ZIP code's heat risk for the coming week on a five-step scale, from low to severe, based on forecast temperatures and local health data. SJVAir imports the daily scores for every Valley ZIP code so heat risk can be shown alongside air quality.
Datasets that combine environmental, health, and socioeconomic indicators to identify communities most impacted by pollution and support equity-focused decision making.
CalEnviroScreen is a mapping and screening tool developed by the California Office of Environmental Health Hazard Assessment (OEHHA). It combines environmental, health, and socioeconomic data from state and federal sources to identify communities most affected by pollution and socioeconomic burdens, helping guide California's environmental justice policies and investments. On the Facility Emissions Explorer, SJVAir summarizes the census tracts in each region and near-me search, and each facility's own tract, by their CalEnviroScreen percentiles and the state's SB 535 disadvantaged-community designations.
The Healthy Places Index (HPI), developed by the Public Health Alliance, maps social and environmental conditions that shape health outcomes across California. By combining indicators such as education, housing, job opportunities, and environmental quality, HPI highlights community factors strongly linked to life expectancy and supports efforts to advance health equity.
The state records behind the Pesticide Data Explorer: every reported agricultural pesticide application in the San Joaquin Valley, the notices growers file before restricted applications, and the official lists that flag which chemicals are of concern to health.
California's Pesticide Use Reporting (PUR) program, run by the Department of Pesticide Regulation (DPR), has required growers to report every agricultural pesticide application since 1990, down to the product, the amount, the crop, and the square-mile section it was applied to. DPR releases each year's records one to two years after the fact. SJVAir imports the full record for the eight Valley counties and summarizes it by chemical, product, commodity, county, and section.
SprayDays is DPR's statewide notification system for restricted-material pesticide applications. Growers file a notice of intent before applying, and SprayDays publishes the planned applications by location up to four days ahead. SJVAir shows the active notices on its pesticide maps and links to SprayDays for sign-up; it does not send notifications of its own.
The U.S. Environmental Protection Agency's CompTox Chemicals Dashboard is a reference database covering more than a million chemicals, with identifiers, structures, and links to hazard data. SJVAir uses it to match the chemical names in DPR's records to standard identifiers and CAS numbers, so that a chemical can be looked up consistently across the health lists below.
California's Proposition 65 list, maintained by the Office of Environmental Health Hazard Assessment (OEHHA), names the chemicals the state has determined can cause cancer, birth defects, or other reproductive harm. SJVAir marks a chemical as a Prop 65 listing when it appears on the list, and includes those listings in its "chemicals of concern" view.
The California Air Resources Board (CARB) identifies toxic air contaminants (TACs) — airborne substances that may cause serious illness or death — and, with OEHHA, publishes health reference values for them. SJVAir flags pesticide chemicals on CARB's TAC list, since these are the ones whose drift into the air is a recognized concern.
The International Agency for Research on Cancer (IARC), part of the World Health Organization, reviews the evidence on whether agents cause cancer in humans and classifies them into groups, from Group 1 (carcinogenic) through Group 2A and 2B (probably and possibly carcinogenic) to Group 3 (not classifiable). SJVAir shows a chemical's IARC group where one has been assigned and treats Groups 1, 2A, and 2B as chemicals of concern.
The state and federal records behind the Facility Emissions Explorer: what each permitted facility in the San Joaquin Valley reports releasing and how toxic it is, where each one is, its federal compliance record, its reported greenhouse gases, the Valley's dairies, oil and gas wells and observed methane sources, and the county-wide inventories that put them in context.
The California Emission Inventory Development and Reporting System (CEIDARS) is CARB's inventory of emissions from permitted stationary sources — refineries, power plants, dairies, manufacturers, and thousands of smaller facilities — reported each year by the local air districts. SJVAir imports every facility in the eight Valley counties, with its criteria pollutant and toxic emissions for each year from 2010 on.
The Consolidated Table of OEHHA/CARB-approved health values lists, for each toxic air contaminant, the cancer potency and the reference exposure levels California's Hot Spots program uses in risk assessments. SJVAir uses it to weight facilities' reported toxics by toxicity, so diesel particulate and hexavalent chromium rank above high-volume, low-toxicity solvents.
The California Emission Projection Analysis Model (CEPAM) is CARB's county-level emissions inventory, covering every source category — cars and trucks, off-road equipment, farming, wildfires, and consumer products as well as permitted facilities — projected from a 2017 base year. SJVAir uses its county totals to show how much of a county's pollution comes from the facilities on the map, and how much from everything else.
CARB's California Dairy & Livestock Database (CADD) locates the state's dairies and counts each one's herd by year, with the anaerobic digesters that capture manure methane. Coverage of the Valley's dairies grew in 2019. SJVAir shows the Valley's dairies, year by year, on the explorer's Dairies tab, beside CARB's county estimates of dairy cattle emissions.
CARB's Pollution Mapping Tool maps greenhouse gas, criteria pollutant, and toxic emissions from California facilities, and publishes the coordinates it places each CEIDARS facility at. SJVAir uses those coordinates to locate facilities whose addresses can't be matched to a street — oil fields, pumping plants, remote sites — and in place of geocoder guesses.
EPA's Enforcement and Compliance History Online publishes the Clean Air Act compliance record — inspections, notices of violation, settlements and high-priority violations — that air districts report for the largest permitted sources. SJVAir matches those records to the Valley Air District's facilities and shows each one's record on its facility page, stamped with how far the district's reporting reaches.
EPA's National Emissions Inventory estimates every county's emissions by source every three years, from permitted facilities to livestock, fertilizer, vehicles and dust. SJVAir uses its 2023 ammonia estimates for the eight Valley counties, split by source, to show how small a share of the Valley's ammonia the permitted facilities on the map are, and how much comes from dairy cattle.
The California Geologic Energy Management Division's WellSTAR database is the state's record of every oil and gas well — its operator, field, status and whether it sits in a health protection zone under SB 1137. SJVAir shows the Valley's active, idle and new wells as a map overlay, counts them on region pages, and lists the schools and child-care centers with a well within 3,200 ft.
EPA's Greenhouse Gas Reporting Program collects annual greenhouse-gas totals from the largest emitters — power plants, refineries, landfills, oil and gas fields and heavy industry — with each one's location and its ids in other federal systems. SJVAir imports the Valley's reporters, links them to the Valley Air District's facilities through EPA's facility registry, and shows each one's CO2e, methane and nitrous oxide on its facility page.
California's Mandatory Greenhouse Gas Reporting program publishes a verified annual summary of every large emitter's greenhouse gases, a year sooner than the federal program and including California-only reporters. SJVAir imports the Valley's emitters (only their own emissions, never the fuel that suppliers sell), matches the largest to their permitted facilities by hand and the rest by name and ZIP, and lists each county's largest reporters.
Carbon Mapper is a non-profit that finds methane and CO2 super-emitters from aircraft and satellites and publishes each source's location, estimated emission rate and how often it was seen. SJVAir shows the Valley's methane sources as a map overlay and links each to the nearest dairy or permitted facility. Data by Carbon Mapper®, for non-commercial use.
The California Department of Food and Agriculture's Dairy Digester Research and Development Program funds anaerobic digesters that capture the methane from dairy manure, and publishes each funded project with its grant, completion date and estimated greenhouse-gas reduction. SJVAir links the Valley's projects to the dairies they serve and shows each dairy's grants alongside its herd and any methane plumes observed nearby.
The boundaries and points every page is organized around: counties, cities and census-designated places, ZIP codes, urban areas, air districts, the square-mile sections pesticide use is reported by, school districts, and the schools and child care centers shown alongside pesticide data and near emitting facilities and oil and gas wells. Most of it comes through the California Open Data Portal, maintained there by the state department named on each dataset.
The Census Bureau's TIGER/Line files are the reference geography for the United States. SJVAir takes its ZIP codes (as ZIP Code Tabulation Areas), census tracts, and congressional districts directly from TIGER/Line, and the county and place boundaries below are the Bureau's as well, republished by the state. The Bureau's geocoder also places emissions facilities at their street addresses.
The California Department of Technology publishes the state's county and place boundaries on the California Open Data Portal, drawn from the Census Bureau's TIGER/Line files. SJVAir's eight Valley counties and its cities and census-designated places come from this dataset.
The California Air Resources Board publishes the boundaries of California's 35 local air districts, the agencies that permit and regulate stationary sources. SJVAir uses them to show which district oversees each facility, with the district's contact details and complaint line taken from CARB's district directory.
The California Department of Transportation maintains the 2020 Adjusted Urban Areas, the Census Bureau's urban areas as adjusted by Caltrans and the state's metropolitan planning organizations for transportation planning. SJVAir uses them to group cities and their surrounding communities into the places you can search for.
The California Department of Conservation publishes the Public Land Survey System (PLSS) sections for the state — the square-mile grid of meridian, township, range, and section that pesticide use reports are located by. SJVAir's section maps and section pages use these official geometries unchanged.
The Department of Education publishes school district boundaries, with each district's enrollment and demographics, and the directory of public and private schools with their locations. SJVAir uses the district boundaries as regions and shows the schools alongside pesticide use in each district, and on the Facility Emissions Explorer lists the schools near each facility and near oil and gas wells.
The California Department of Social Services licenses child care centers through its Community Care Licensing Division and publishes the facility list, with addresses and capacities. SJVAir shows the licensed child care centers in the Valley alongside schools on its pesticide maps and district pages, and near facilities and oil and gas wells on the Facility Emissions Explorer.