City report · Penang, Malaysia
Bukit Mertajam Air quality today
Air quality in Bukit Mertajam currently reads AQI 56 (Moderate): Unusually sensitive people should consider limiting long outdoor exertion.
AQI 56
Air quality right now
Moderate
- PM2.5, fine particles (µg/m³)
- 11.8
- tree cover
- 42.3%
- trees in this area
- 129K
- more trees needed
- 0
Measured across a 2 km radius around Bukit Mertajam, Penang, Malaysia (12.57 km²), from a satellite image of Jun 14, 2026. Lower AQI is better: 0–50 is Good, above 300 is Hazardous.
Bukit Mertajam · AQI 56 (Moderate)
Bukit Mertajam's tree count comes to 129,434 trees across 12.24 km² of land, already at or above the 30% tree-cover level considered healthy for this area.
Air quality detail
Air quality in Bukit Mertajam today: AQI 56, Moderate
Main pollutant: PM2.5 · Observed Nov 11, 23:00 local time via World Air Quality Index Project ground stations, US EPA index. Values in µg/m³.
Ground station · Perai, Pulau Pinang, Malaysia, 4.5 km away · median of 2 stations
Health signal
Unusually sensitive people should consider limiting long outdoor exertion.
PM2.5
11.8
PM10
17.3
NO₂
—
O₃
—
SO₂
—
CO
—
Data: World Air Quality Index Project, Malaysia Department of Environment (DOE); Air Polluant Index Management System
- Outdoor exercise
- Fine for most people; unusually sensitive people should take long or hard exercise easier
- Windows
- Fine to open; close them if you are sensitive to pollution
- Mask
- Not needed for most people
- Air purifier
- Worth running if you are sensitive
Over the last 7 days, the CAMS air-quality model put Bukit Mertajam's daily AQI at 49 on average, from 40 on Nov 5 to an hourly peak of 74 on Nov 6.
This is the US EPA AQI. How it differs from Malaysia's API (IPU) · The full guide
Where Bukit Mertajam stands: the most polluted cities in the world right now · the cleanest
Tree cover detail
Tree cover in Bukit Mertajam: Healthy tree cover
42.3% tree cover against a 30% healthy-neighborhood target, across 12.24 km² of land.
Trees in this area
129,434
Target trees
129,434
More trees needed
0
CO₂ if planted / yr
0 kg
Deforestation · 2001–2025
How much forest has Bukit Mertajam lost?
Since 2001, the area within 10 km of Bukit Mertajam has lost about 3,420 hectares of forest (about 4,800 football pitches): 35% of the forest it had in 2000. Most of it (99%) was deforestation, forest cleared for good, mainly for farms, pasture and plantations.
2017: satellite photo from February 2017 of a 5 × 5 km area about 7 km northeast of the city center.
- Forest lost since 2001
- 3,420 haabout 4,800 football pitches
- Share of its forest
- 35%of what there was in 2000
- Cleared for good
- 3,370 hadeforestation: turned into farms, mines or towns
Forest loss has stayed about the same: about 125 hectares a year in 2021–2025, against 157 hectares a year in 2016–2020. The worst year was 2014, when about 321 hectares of forest were lost.
Hectares of forest lost each year
Show the figures as a table
| Year | Cleared for good | Can grow back | Total |
|---|---|---|---|
| 2001 | 36 ha | under 1 ha | 36 ha |
| 2002 | 122 ha | 1 ha | 123 ha |
| 2003 | 53 ha | under 1 ha | 53 ha |
| 2004 | 122 ha | 1 ha | 123 ha |
| 2005 | 112 ha | 2 ha | 114 ha |
| 2006 | 98 ha | under 1 ha | 98 ha |
| 2007 | 70 ha | under 1 ha | 71 ha |
| 2008 | 94 ha | under 1 ha | 94 ha |
| 2009 | 157 ha | 1 ha | 158 ha |
| 2010 | 139 ha | under 1 ha | 139 ha |
| 2011 | 104 ha | under 1 ha | 104 ha |
| 2012 | 292 ha | under 1 ha | 292 ha |
| 2013 | 116 ha | 2 ha | 118 ha |
| 2014 | 312 ha | 9 ha | 321 ha |
| 2015 | 168 ha | 2 ha | 170 ha |
| 2016 | 183 ha | under 1 ha | 183 ha |
| 2017 | 156 ha | under 1 ha | 156 ha |
| 2018 | 171 ha | 1 ha | 172 ha |
| 2019 | 130 ha | 1 ha | 131 ha |
| 2020 | 140 ha | 1 ha | 141 ha |
| 2021 | 123 ha | under 1 ha | 123 ha |
| 2022 | 66 ha | under 1 ha | 67 ha |
| 2023 | 157 ha | under 1 ha | 157 ha |
| 2024 | 133 ha | 13 ha | 146 ha |
| 2025 | 120 ha | 11 ha | 131 ha |
What is causing deforestation around Bukit Mertajam?
- Farms, pasture and plantationscleared for good53% · 1,810 ha
- Towns and roadscleared for good41% · 1,400 ha
- Mining and energycleared for good5% · 171 ha
Also: logging, shifting farming, unknown causes.
Causes for 2025 are estimates, based on what caused forest loss in the same places up to 2024.
Forest gained and lost, 2000–2020
- Forest in 2000
- 13,500 ha
- Forest in 2020
- 12,400 ha
- Overall change
- −1,120 haless forest than in 2000
Comparing satellite maps from 2000 and 2020, the forest around Bukit Mertajam shrank from about 13,500 hectares to 12,400 hectares, a net loss of about 1,120 hectares (−8.3%). New forest grew on about 1,280 hectares, but 2,400 hectares were lost.
These 2000 and 2020 maps, from the University of Maryland, count any land with trees taller than 5 m as forest, including plantations and orchards. Forest that was cut or burned and had grown back by 2020 counts in both years, so the loss here is smaller than the yearly figures.
These figures cover everything within 10 km of the city center, a wider area than the report above, because forest is usually lost at a city's edges.
Source: Hansen/UMD/Google/USGS/NASA, Global Forest Change (GFC-2025-v1.13); causes: WRI/Google DeepMind drivers of forest loss; both CC BY 4.0, summed by Airleaf for each area. Forest gained and lost 2000–2020: Potapov et al. 2022, UMD GLAD Global Land Cover and Land Use Change, CC BY 4.0. Images: contains modified Copernicus Sentinel data. How it's measured
In the same region
Measured cities near Bukit Mertajam
Same 2 km radius, same index — so they compare directly.
- Butterworth12.1 km
Malaysia
- Tree cover
- 21%
- Air quality
- 54
- Tasek Glugor13.5 km
Malaysia
- Tree cover
- 58%
- Air quality
- 53
- Paya Terubong20.7 km
Malaysia
- Tree cover
- 79%
- Air quality
- 48
- Bayan Lepas23.9 km
Malaysia
- Tree cover
- 44%
- Air quality
- 48
- Kota Kuala Muda27.2 km
Malaysia
- Tree cover
- 29%
- Air quality
- 55
- Sungai Petani31.7 km
Malaysia
- Tree cover
- 29%
- Air quality
- 52
Build your own
Compare Bukit Mertajam with anywhere
This place
Bukit Mertajam
Use this data
Put Bukit Mertajam's numbers on your site
Free to embed. Updates itself as the measurement refreshes.
Frequently asked
Questions about Bukit Mertajam
What is the air quality (AQI) in Bukit Mertajam right now?
The latest reading for Bukit Mertajam shows an AQI of 56 (Moderate), measured Nov 11, 23:00 local time by 2 ground monitoring stations via OpenAQ (the median of their readings; the nearest is Perai, Pulau Pinang, Malaysia, 4.5 km away). The main pollutant is PM2.5. Unusually sensitive people should consider limiting long outdoor exertion.
Is it safe to exercise outside in Bukit Mertajam today?
At AQI 56 (Moderate): fine for most people; unusually sensitive people should take long or hard exercise easier. Windows: fine to open; close them if you are sensitive to pollution. Masks: not needed for most people. The reading changes through the day, so check again before a long run or ride.
What has the air quality in Bukit Mertajam been like this week?
Over the last 7 days, the CAMS air-quality model put Bukit Mertajam's daily AQI at 49 on average, from 40 on Nov 5 to an hourly peak of 74 on Nov 6. No day averaged above 100, the level where the air turns unhealthy for sensitive groups.
Is Bukit Mertajam's AQI the same as Malaysia's API (IPU)?
No. Airleaf shows the US EPA Air Quality Index (AQI), the scale used by IQAir and most air-quality apps. Malaysia's Department of Environment (Jabatan Alam Sekitar) publishes its own Air Pollutant Index, the API or Indeks Pencemar Udara (IPU), every hour for each of its monitoring stations on APIMS (apims.doe.gov.my). Both scales call 0–50 good and 51–100 moderate; above that the IPU runs 101–200 unhealthy, 201–300 very unhealthy and over 300 hazardous. The two use different breakpoints and averaging times, so the numbers for the same hour often differ. For the official IPU reading, check the nearest station on APIMS.
How much forest has the area around Bukit Mertajam lost since 2001?
Since 2001, the area within 10 km of Bukit Mertajam has lost about 3,420 hectares of forest (about 4,800 football pitches): 35% of the forest it had in 2000. Most of it (99%) was deforestation, forest cleared for good, mainly for farms, pasture and plantations. Forest loss has stayed about the same: about 125 hectares a year in 2021–2025, against 157 hectares a year in 2016–2020. Comparing satellite maps from 2000 and 2020, the forest around Bukit Mertajam shrank from about 13,500 hectares to 12,400 hectares, a net loss of about 1,120 hectares (−8.3%). New forest grew on about 1,280 hectares, but 2,400 hectares were lost.
What is the tree count in Bukit Mertajam?
Bukit Mertajam has an estimated 129,434 trees across the 12.24 km² of land measured — 42.3% tree cover, already past the 30% tree-cover target set for this area.
How many more trees does Bukit Mertajam need?
Bukit Mertajam has already reached its tree-cover target, so no additional trees are needed to close the gap.
How are Bukit Mertajam's air quality and tree cover measured?
Air quality is measured by ground monitoring stations near Bukit Mertajam, via OpenAQ; the 7-day trend is the Open-Meteo / CAMS model's estimate. Tree cover is measured from Sentinel-2 L2A (ESA Copernicus) via Earth Search satellite imagery at 10 m detail across a 2 km radius around Bukit Mertajam; the tree count is an estimate derived from that cover.
See your own area
What does your neighborhood look like?
Pick any point and radius to get the same air-quality and tree-cover breakdown.
Check my address