Air quality in Joetsu, Japan today
Mr. Duck’s Air Quality Score
Good air today for Joetsu, Japan
This friendly indicator summarizes the latest city readings. For health guidance, please see: EPA AirNow or WHO.
Air quality today
The air quality in Joetsu today is classified as Good. The primary pollutant identified is PM2.5, with a measured concentration of 6.0 µg/m³ reported from two valid observations. Data are shown via OpenAQ.
Overall conditions meet the Good category criteria based on the available measurements. This page is informational; for health guidance, use official sources such as EPA AirNow or WHO.
Latest sensor values
PM categories follow US EPA AQI breakpoints, shown here as an estimate derived from the latest valid measurements (this project does not compute EPA NowCast/24-hour AQI yet).
What the data includes
The Joetsu air‑quality record contains five measured pollutants – nitrogen monoxide (NO), nitrogen dioxide (NO₂), total nitrogen oxides (NOX), fine particulate matter (PM2.5) and sulfur dioxide (SO₂). All data come from a single monitoring location at 上越市大字三橋８４０, so the station count is one row per pollutant.
The most recent updates are split between two time periods. The nitrogen‑related gases (NO, NO₂ and NOX) were last refreshed on 2024‑04‑01 01:00 UTC, which means those values are over a year old. In contrast, the PM2.5 and SO₂ measurements have been updated within the past three days, with timestamps of 2026‑02‑10 22:00 UTC. This mix shows that while particulate and sulfur data are current, the nitrogen species reflect older conditions.
Across the five pollutants the recorded values show no variation – each metric has a single observed figure. NO is consistently 0.003 ppm, NO₂ stays at 0.007 ppm, NOX at 0.010 ppm, PM2.5 remains 6.0 µg/m³ and SO₂ holds steady at 0.001 ppm. Because the dataset contains only one reading per pollutant, the median, minimum and maximum are identical, indicating a lack of spread in the available data.
Overall, the coverage is limited to one monitoring site, and the freshness differs markedly between gas‑phase nitrogen compounds and the more recent particulate and sulfur measurements. Users should keep in mind that conditions can change across different neighborhoods and times of day, and the present dataset does not capture those variations.
Learn more about sources and filtering: About the data.
Trusted references: WHO (Air pollution) · US EPA AirNow · European Environment Agency (Air)
Latest sensor values (bars)
PM categories follow US EPA AQI breakpoints, shown here as an estimate derived from the latest valid measurements (this project does not compute EPA NowCast/24-hour AQI yet).
Data notes
The data shown for Joetsu is based on two valid measurements and was refreshed recently, having been updated within 3 days (last update: 2026‑02‑10 22:00 UTC). This snapshot reflects conditions at the time of sampling; air quality can vary by location and moment within the city, so values may differ from what you experience elsewhere or later in the day.
OpenAQ station rows
| Station | Parameter | Value | Unit | Last updated |
|---|---|---|---|---|
| 上越市大字三橋８４０ | no | 0.003 | ppm | 2024-04-01 01:00 UTC |
| 上越市大字三橋８４０ | no2 | 0.007 | ppm | 2024-04-01 01:00 UTC |
| 上越市大字三橋８４０ | nox | 0.01 | ppm | 2024-04-01 01:00 UTC |
| 上越市大字三橋８４０ | pm25 | 6.0 | µg/m³ | 2026-02-10 22:00 UTC |
| 上越市大字三橋８４０ | so2 | 0.001 | ppm | 2026-02-10 22:00 UTC |