Air quality comparison · Gabon, 272 km apart
Libreville vs Oyem Air quality index (AQI) today
Oyem has cleaner air than Libreville right now: AQI 41 (Good) against 53 (Moderate).
That puts them in different EPA bands, so the health advice differs today. Over the past 7 days, on modeled daily averages, both averaged AQI 42. Oyem has lost more forest since 2001. Oyem has more tree cover.
Gabon
AQI 53
Moderate
Cleaner right now
- PM2.5
- 11.7 µg/m³
- Main pollutant
- PM2.5
- Source
- Model estimate
- Reading
- Nov 10, 22:00 local
Gabon
AQI 41
Good
Cleaner right now
- PM2.5
- 9 µg/m³
- Main pollutant
- PM2.5
- Source
- Model estimate
- Reading
- Nov 10, 16:00 local
Updated . Lower is better on the US EPA index: 0–50 is Good, above 300 is Hazardous. Measured by Airleaf.
Libreville53Oyem41
Head to head
Libreville vs Oyem at a glance
Oyem is ahead on 4 of 6 measures, and Libreville on 1. The better figure in each row is marked.
| Libreville | Oyem | |
|---|---|---|
| Air quality nowUS AQI. Lower is better. | 53 | 41 (better) |
| PM2.5Fine particles, µg/m³. | 11.7 | 9 (better) |
| Past week's averageUS AQI, 7 days. | 42 | 42 |
| Forest lost since 2001Within 10 km of the center. | 1,510 ha (better) | 5,520 ha |
| Tree coverWithin 2 km of the center. | 12.3% | 49.1% (better) |
| Trees still neededTo reach a healthy canopy. | 46.6K | 0 (better) |
Air quality today
What is the air like in Libreville and Oyem right now?
Oyem has cleaner air than Libreville right now: AQI 41 (Good) against 53 (Moderate). PM2.5 is setting the index in both.
Both readings are model estimates, with no ground station close enough to either.
LibrevilleOyem
Concentrations at the same moment as the index above, for the pollutants both places report. Lower is better. The dark marks on the PM2.5 and PM10 rows show the WHO's 24-hour guidelines (15 and 45 µg/m³).
Libreville: Model estimate · no ground station nearby. Data: Open-Meteo / CAMS, US EPA index.
Oyem: Model estimate · no ground station nearby. Data: Open-Meteo / CAMS, US EPA index.
The past week
Which had cleaner air over the past 7 days?
Over the past 7 days, on modeled daily averages, both averaged AQI 42. A single reading can catch a city on a bad afternoon; the week says whether it was the weather or the place.
- Cleaner days
- Libreville2Oyem4
- Average AQI
- Libreville42Oyem42
- Worst day, AQI
- Libreville57Oyem53
The daily numbers (7 days)
| Day | Libreville | Oyem |
|---|---|---|
| Nov 4 | 37 | 38 |
| Nov 5 | 38 | 35 |
| Nov 6 | 38 | 38 |
| Nov 7 | 48 | 44 |
| Nov 8 | 57 | 53 |
| Nov 9 | 45 | 44 |
| Nov 10 | 28 | 40 |
Daily averages from the CAMS atmospheric model for both places, so the week compares like with like. They can differ from today's reading at the top of the page wherever that comes from a ground station.
What it means today
Is it safe to go outside in Libreville and Oyem today?
Libreville (AQI 53, Moderate): Unusually sensitive people should consider limiting long outdoor exertion.
Oyem (AQI 41, Good): Air quality is satisfactory for everyone.
Exercise outdoors
- Libreville
- Fine for most people; unusually sensitive people should take long or hard exercise easier.
- Oyem
- A good day to be active outside.
Windows
- Libreville
- Fine to open; close them if you are sensitive to pollution.
- Oyem
- Open them to air the house.
Masks
- Libreville
- Not needed for most people.
- Oyem
- Not needed.
Air purifier
- Libreville
- Worth running if you are sensitive.
- Oyem
- Not needed.
Against everywhere else
How do Libreville and Oyem compare with the rest of the world?
Right now Libreville's air is cleaner than 56% of the 5,420 places Airleaf tracks, and Oyem's is cleaner than 69%. Within Gabon, that is 25% and 75% of its 5 measured places.
Cleaner air than…
- Libreville
- Beats 56%
- Oyem
- Beats 69%
More tree cover than…
- Libreville
- Beats 27%
- Oyem
- Beats 92%
Includes model estimates as well as station readings, so it can differ from our most polluted and cleanest air rankings, which use station readings only.
Deforestation · 2001–2025
Which has lost more forest, Libreville or Oyem?
Oyem has lost more: about 5,520 ha of forest within 10 km of its center from 2001 to 2025, against 1,510 ha around Libreville. 1,070 ha of that was cleared for good, for farms, mines or towns.
Measured within 10 km of each center, from the yearly satellite maps of forest loss: a wider circle than the one for tree cover, because forest is usually lost at a city's edges.
Worst year: 2014, with 215 ha lost.
Worst year: 2019, with 480 ha lost.
| Libreville | Oyem | |
|---|---|---|
| Forest lost since 2001Cleared, burned or logged. | 1,510 ha (better) | 5,520 ha |
| Share of its forestOf what it had in 2000. | 20% | 18% (better) |
| Cleared for goodTurned into farms, mines or towns. | 1,340 ha | 1,070 ha (better) |
| Recent trend2021–2025 against the five years before. | Holding steady | Holding steady |
| Main known cause | Towns and roads (78%) | Shifting farming (79%) |
Satellite timelapses
Watch both change, year by year
A clear satellite photo a year of the land around each city. Press play, turn on the forest cleared since the first year, or drag the before and after.
Libreville
2017: satellite photo from February 2017 of a 5 × 5 km area about 7 km northeast of the city center.
Oyem
2019: satellite photo from January 2019 of a 5 × 5 km area about 4 km northwest of the city center.
Trees
Which has more trees, Libreville or Oyem?
Oyem has more tree cover: 49.1% of the land within 2 km of its center against 12.3% around Libreville, or about 154,252 trees against 32,382.
The dark mark is each place's canopy target: 30% of the land, raised where air quality is poor.
| Libreville | Oyem | |
|---|---|---|
| Trees standingEstimated from the canopy area. | 32.4K | 154K (better) |
| Trees still neededTo reach the target. Fewer is better. | 46.6K | 0 (better) |
| CO₂ absorbed each yearBy the trees already standing. | 712K kg | 3.4M kg (better) |
Tree cover on the satellite image
The same 2 km radius around each center, with the tree cover the satellite found marked on it.
Reading these numbers
How this comparison is made
Air quality index
The US EPA index, computed from current pollutant concentrations: ground stations where a place has them nearby, and the CAMS atmospheric model everywhere else. It moves hour to hour, so it is a snapshot rather than a verdict on either place. The guideline marks are from the WHO's 2021 air quality guidelines.
Trees and forest
Tree cover is the share of ground under canopy within 2 km of each center, read from Sentinel-2 satellite imagery at 10 m detail. It measures that circle, not the whole municipality, which is what makes the two comparable. Forest loss comes from the University of Maryland's Global Forest Change maps.
More on the method on the About Airleaf page.
Frequently asked
Libreville vs Oyem: your questions answered
Is Oyem cleaner than Libreville?
On air quality, yes, right now: Oyem reads AQI 41 against 53, a gap of 12 points on the US EPA index. This is a live reading rather than an annual average, so it can reverse within a day. Over the past 7 days, on modeled daily averages, both averaged AQI 42.
Is it safe to exercise outdoors in Libreville and Oyem today?
In Libreville, at AQI 53: Unusually sensitive people should consider limiting long outdoor exertion. In Oyem, at AQI 41: Air quality is satisfactory for everyone.
Which has lost more forest, Libreville or Oyem?
Oyem has lost more: about 5,520 ha of forest within 10 km of its center from 2001 to 2025, against 1,510 ha around Libreville. 1,070 ha of that was cleared for good, for farms, mines or towns.
Which has more trees, Libreville or Oyem?
Oyem has more tree cover: 49.1% of the land within 2 km of its center against 12.3% around Libreville, or about 154,252 trees against 32,382. Both figures describe the same-sized circle of ground around each center, not the whole municipality.
How many more trees do Libreville and Oyem need?
Libreville needs about 46,598 more to reach its canopy target of 30%, and Oyem about 0 to reach 30%. The target starts at 30% of the land and rises where air quality is poor.
Are Libreville and Oyem measured the same way?
The method is the same: the US EPA index for air, and Sentinel-2 satellite imagery at 10 m detail over an identical radius for trees. Both readings are model estimates, with no ground station close enough to either. Nothing is adjusted for population, city limits or climate.
How often does the Libreville vs Oyem comparison update?
The air readings refresh about once an hour, and each reading's local time is shown at the top of the page. Tree cover comes from the latest clear satellite image of each area (Jun 29, 2026 and Mar 25, 2026), and the forest figures are published yearly.
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