AirNow by Skymory

South Korea · Asia/Seoul

Siheung air quality

AQI estimate unavailable

CAMS model-based US AQI estimate

Complete eligible model windows are not available within the stale policy; pollutant concentrations are shown below.

Model values for Oct 31 15:00 KST · CAMS model estimate, may differ from monitoring stations and street-level conditions

Data may be delayed · Page generated 2026-10-31 15:22 KST

AirNow by Skymory is an independent service; it is not affiliated with or endorsed by U.S. EPA or the official AirNow service.

Pollutants now (modeled)

  • PM2.5Fine particles5.5 µg/m³
  • PM10Coarse particles6.0 µg/m³
  • O3Ozone71.7 µg/m³
  • NO2Nitrogen dioxide13.1 µg/m³
  • SO2Sulphur dioxide9.2 µg/m³
  • COCarbon monoxide192.8 µg/m³

Next 24 hours: PM2.5

Modeled PM2.5 forecast (µg/m³)Actual model samples spaced by their valid times. Range 6.4 to 41.9. Forecast, not observations.Oct 31 16:00 KSTNov 01 15:00 KST
Modeled PM2.5 forecast (µg/m³) · 6.4–41.9; actual sample times, no interpolated hourly values.

Pollutant forecast

Hourly model samples in local time; no interpolation.

Local timePM2.5 µg/m³PM10 µg/m³O3 µg/m³NO2 µg/m³SO2 µg/m³CO µg/m³
6.47.066.815.99.7198.9
7.98.553.126.110.9215.6
13.514.112.159.915.9302.1
20.321.05.464.123.8398.9
25.426.31.866.431.3462.1
31.132.10.166.740.4528.7
36.937.90.065.449.4597.4
40.841.80.064.651.7651.7
41.942.80.063.546.6681.9
39.139.80.061.438.7657.3
37.738.30.059.534.6650.0
35.836.30.058.832.8633.1
36.136.60.056.531.1649.5
36.637.00.054.632.4672.4
35.535.90.055.434.5671.5
35.436.40.158.240.5670.6
35.036.20.759.944.8652.0
37.538.51.656.747.6714.1
34.635.72.054.743.9621.7
31.832.94.053.137.9499.9
29.330.54.653.333.4435.3
26.628.16.853.028.1387.4
25.026.46.853.724.9367.1
23.124.98.657.422.7342.9
Data details: about this air quality estimate

Values are modeled by the Copernicus Atmosphere Monitoring Service (CAMS) global forecast, extracted and converted by Skymory for this city. They are model estimates on a coarse grid, not measurements from monitoring stations, and they do not resolve street-level exposure.

  • Model initialization: 2026-10-30T12:00:00+00:00. Values valid: Oct 31 15:00 KST. Retrieved: 2026-10-31T03:36:24.677949+00:00.
  • Page generated from a snapshot with data state STALE_USABLE; model age 18.4 hours at generation.
  • Nearest valid 0.4° model grid cell, about 21 km from the city point.
  • Gases are converted with matching model-level 137 temperature, humidity, surface pressure (lnsp) and hybrid coefficients; particulate matter is read directly from the surface fields.
  • AQI estimate completeness: UNAVAILABLE (COMPLETE means all six pollutants have a complete model window).

The AQI estimate applies EPA breakpoints (May 2026) to explicit trailing model windows (PM 24 h, CO 8 h, NO2 1 h, SO2 and O3 per EPA rules). It is not a station observation, official daily maximum or NowCast, and the official AQI field remains unavailable.

Surface compatibility by pollutant

PollutantSurface compatibility
PM2.5DIRECT_SURFACE
PM10DIRECT_SURFACE
O3DERIVABLE_SURFACE
NO2DERIVABLE_SURFACE
SO2DERIVABLE_SURFACE
CODERIVABLE_SURFACE

Source and license

Contains modified Copernicus Atmosphere Monitoring Service information 2026; city extraction and concentration conversion. CAMS global atmospheric composition forecasts (ECMWF/CAMS). CC BY 4.0.

Provider times stay separate from page generation: collecting data or regenerating this page never resets the source time. Data sources and methodology

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