Air quality index for Busan, as of (Asia/Seoul). Values update hourly — see this page for the current reading and hourly forecast. Today's peak: AQI 75 at 03:00 local time.

airindex·today

Air Quality in Busan

Busan is now at AQI 66 (moderate), below today's high of AQI 75 in the same band around 03:00. Today's main contributor is fine particulate matter (PM₂.₅), at 12 µg/m³.

Now, Oct 17at 21:00
66Moderate
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

By pollutant

  • PM₂.₅ fine particles · sets the index nowAQI 66
  • O₃ ozoneAQI 44
  • PM₁₀ coarse particlesAQI 26
  • NO₂ nitrogen dioxideAQI 6
  • SO₂ sulfur dioxideAQI 2
  • CO carbon monoxideAQI 2
Unusually sensitive people should consider reducing prolonged or intense outdoor activity

Modeled forecast data. AQI values come from atmospheric models (CAMS via Open-Meteo), not local monitoring stations. Readings can differ from ground-level conditions — for exact street-level values, consult an official air quality station near you. The forecast is calculated for a grid square, roughly 11 km across Europe and 45 km elsewhere, and air quality can vary within one square.

The next 48 hours

Hourly air quality index for Busan · Local time (GMT+9)

Today, Oct 17
Tomorrow, Oct 18
50
Peak 75 · 03:00
Peak 78 · 17:00
0:00
6:00
12:00
18:00
0:00
6:00
12:00
18:00

Good ≤ 50

Now
Show hourly data table
TimeAQIPM₂.₅µg/m³PM₁₀µg/m³O₃µg/m³NO₂µg/m³SO₂µg/m³COmg/m³°C
Today
00:007232413069200.7318°
01:007329373070170.7118°
02:007425332972140.6819°
03:007522303171120.6419°
04:007520283665110.6019°
05:007519284355100.5619°
06:0075202951479.80.5220°
07:0075223258429.60.4620°
08:0074243465389.60.4121°
09:0074162487249.70.3622°
10:0074142396188.20.3222°
11:007414231089.76.10.2623°
12:007413231163.94.60.2123°
13:007413221172.34.10.2023°
14:007312211142.94.10.2023°
15:007312201094.94.20.2124°
16:007311191008.94.30.2023°
17:0072111988144.50.2123°
18:0072121980184.60.2022°
19:0070132078174.60.2022°
20:0068132079144.50.1921°
21:0066121980124.30.1821°
22:0064111780114.00.1821°
23:0062101679103.60.1721°
Tomorrow
00:00601016789.63.40.1721°
01:00581116769.03.40.1721°
02:00571116748.73.60.1721°
03:00559.314739.44.00.1822°
04:00549.61471124.90.2122°
05:0053111569166.10.2522°
06:0052121672187.10.2821°
07:0052141885187.80.2921°
08:00511519103168.30.2922°
09:00501522118148.40.2823°
10:00501623125117.70.2724°
11:005015221296.66.50.2424°
12:005015221304.25.60.2224°
13:005017241294.35.40.2124°
14:005617241265.95.60.2124°
15:006817241227.65.70.2124°
16:007517241169.25.70.2024°
17:00781419110115.70.2024°
18:00761418105125.70.2024°
19:00721419104115.50.1924°
20:006714191059.35.30.1824°
21:006218251058.25.10.1824°
22:005716221048.05.00.1824°
23:005414191038.25.00.1824°

Today at a glance

Worst hour
03:00
peaks at AQI 75
Tomorrow
Much the same, peak 78
peak at 17:00

The week, hour by hour

Little changes tomorrow — the forecast peak is AQI 78 (moderate) around 17:00. The whole 5-day outlook sits in the moderate band, with daily peaks from AQI 56 to AQI 78 and Sunday the highest.

Each cell is one forecast hour, coloured by air quality band. A ring marks the day's worst hour. The blue ring marks the current hour.

TodayOct 17
Peak 75 at 03:00
Overcast24° / 18°
SunOct 18
Peak 78 at 17:00
Overcast24° / 21°
MonOct 19
Peak 56 at 23:00
Thunderstorm25° / 22°
TueOct 20
Peak 74 at 13:00
Light rain showers22° / 16°
WedOct 21
Peak 61 at 00:00
Light rain showers23° / 11°

Pollutants right now

Every pollutant on the same AQI scale as the big number above. The index only ever equals the worst score — pollutants don't add up.

050100150+
PM₂.₅fine particles · sets the index now
66
O₃ozone
44
PM₁₀coarse particles
26
NO₂nitrogen dioxide
6
SO₂sulfur dioxide
2
COcarbon monoxide
2
GoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardous

The colors cover a wide area, not a street. The forecast works in squares of roughly 11 km across Europe and 45 km elsewhere, so the air where you actually are can differ from the shade under the city.

Check air quality in: Ulsan · Changwon · Gyeongsan-si · Jinju · Gyeongju

About Busan

CountrySouth Korea, Busan
TimezoneAsia/Seoul (UTC+9)
Coordinates35.10° N, 129.03° E
Population≈ 3.29M

Air quality in Busan — common questions

What is the air quality in Busan right now?

The current air quality index (AQI) in Busan is 66 (Moderate). Today's forecast peak is AQI 75 (Moderate) at 03:00 local time, and tomorrow's forecast peak is AQI 78. These values come from the CAMS forecast model, not from a local monitoring station.

When is air quality expected to be worst in Busan today?

Today's forecast puts the highest AQI in Busan at 03:00 during the night, reaching 75. The largest contributor right now is PM₂.₅. Air quality shifts through the day with traffic, wind, how well the air mixes and sunlight, so the hourly chart above shows the pattern for today and tomorrow.

What will the air quality be in Busan tomorrow?

Tomorrow's forecast peak for Busan is AQI 78 (Moderate) around 17:00 local time, much the same as today's peak of 75. A next-day forecast is less certain than today's, so check back in the morning for the updated hourly curve.

Which pollutants drive the AQI in Busan today?

The air quality index in Busan is set by PM₂.₅ right now. The modelled level this hour is 12 µg/m³, within the World Health Organization's 2021 guideline of 15 µg/m³. The others follow: O₃ (AQI 44), PM₁₀ (AQI 26), NO₂ (AQI 6), SO₂ (AQI 2), and CO (AQI 2).
Pollutant levels in Busan at the current hour
PollutantSub-indexLevelWHO 2021Vs guideline
PM₂.₅6612 µg/m³15 µg/m³ (24h)0.8×
O₃4480 µg/m³100 µg/m³ (8h)0.8×
PM₁₀2619 µg/m³45 µg/m³ (24h)0.4×
NO₂612 µg/m³25 µg/m³ (24h)0.5×
SO₂24.3 µg/m³40 µg/m³ (24h)0.1×
CO20.18 mg/m³4 mg/m³ (24h)0.05×
The overall AQI is the highest of the six sub-indices, so the pollutant with the highest sub-index is the one setting the number shown on this page. Sub-indices are computed over the EPA's averaging periods, while the levels are modelled values for the current hour.

Is air quality improving in Busan this week?

Over the 5-day forecast, daily peak AQI in Busan falls from 75 to 61. These are peak values: each day still has cleaner and dirtier hours, which the chart above shows. The worst day of the stretch is Sunday, peaking at AQI 78.

How is air quality forecast for Busan, Busan, South Korea?

Air quality for Busan is forecast with the Copernicus Atmosphere Monitoring Service (CAMS), operated by ECMWF. CAMS models hourly levels of PM2.5, PM10, ozone, nitrogen dioxide, sulfur dioxide and carbon monoxide. Busan lies at 35.1° N in the Northern Hemisphere, which sets the seasonal pattern of sunlight that drives much of the chemistry behind these pollutants. AQI values on this page use the US EPA scale.
About the Air Quality Index

What is the Air Quality Index (AQI)?

The Air Quality Index (AQI) is a tool developed by the U.S. Environmental Protection Agency (EPA) to communicate how clean or polluted the air is and what health effects may be of concern. The AQI runs from 0 to 500 and is divided into six color-coded categories: Good, Moderate, Unhealthy for Sensitive Groups, Unhealthy, Very Unhealthy, and Hazardous.

How do I read the AQI values?

Lower AQI values mean cleaner air. An AQI of 0–50 (green) is Good, 51–100 (yellow) is Moderate, 101–150 (orange) is Unhealthy for Sensitive Groups, 151–200 (red) is Unhealthy, 201–300 (purple) is Very Unhealthy, and 301–500 (maroon) is Hazardous. When the AQI exceeds 100, air quality is considered unhealthy — at first for sensitive groups, then for everyone as the AQI rises.

Who are the sensitive groups?

Sensitive groups include people with heart or lung disease, older adults, children and teenagers, people who are pregnant, and people who are active outdoors. These groups are more likely to be affected when air quality is poor. If you are in a sensitive group, you can reduce your exposure by taking fewer and shorter outdoor walks when the AQI is elevated.

Which pollutants are measured?

The AQI covers five major pollutants regulated under the Clean Air Act: ground-level ozone (O₃), particle pollution (PM₂.₅ and PM₁₀), carbon monoxide (CO), sulfur dioxide (SO₂), and nitrogen dioxide (NO₂). An AQI value is calculated for each pollutant, and the highest value determines the overall AQI.

Where does the air quality data come from?

The hourly air quality data comes from the Copernicus Atmosphere Monitoring Service (CAMS), which provides global atmospheric composition forecasts. The data is accessed via Open-Meteo, which provides free, open-source weather and air quality APIs. The AQI categories and health guidance follow the EPA AirNow technical standard (EPA-454/B-24-002).

What are the health effects of poor air quality?

Poor air quality can cause respiratory issues, aggravate asthma and allergies, and increase the risk of cardiovascular problems. Fine particles (PM₂.₅) can penetrate deep into the lungs and bloodstream. The World Health Organization estimates that air pollution causes millions of premature deaths worldwide each year.

How often is the air quality forecast updated?

The CAMS air quality forecast is updated regularly using atmospheric models. Weather data such as temperature and cloud cover comes from Open-Meteo. The forecast provides up to 5 days of hourly air quality predictions.

AQI Levels (US EPA Standard)

Good (0–50) — Air quality is satisfactory — it's a great day to be active outside
Moderate (51–100) — Unusually sensitive people should consider reducing prolonged or intense outdoor activity
Unhealthy for Sensitive Groups (101–150) — Sensitive groups should reduce prolonged or intense outdoor activity. Take more breaks and watch for symptoms such as coughing or shortness of breath
Unhealthy (151–200) — Everyone should reduce prolonged or intense outdoor activity. Sensitive groups should avoid outdoor exertion. Consider moving activities indoors
Very Unhealthy (201–300) — Everyone should avoid prolonged or intense outdoor exertion. Sensitive groups should avoid all outdoor physical activity. Move activities indoors or reschedule
Hazardous (301–500) — Health warning — everyone should avoid all outdoor physical activity. Stay indoors and keep activity levels light. Follow tips for keeping particle levels low indoors

AQI categories and health guidance: EPA AirNow (EPA-454/B-24-002, May 2024). Air quality data: CAMS/Copernicus via Open-Meteo.