Air quality comparison · Yemen, 148 km apart
Al Ḩudaydah vs Sanaa Air quality index (AQI) today
Sanaa has cleaner air than Al Ḩudaydah right now: AQI 42 (Good) against 56 (Moderate).
That puts them in different EPA bands, so the health advice differs today. Over the past 7 days, on modeled daily averages, Sanaa averaged AQI 38 against 62, and it was the cleaner of the two on 7 of those days. Sanaa has more tree cover.
Yemen
AQI 56
Moderate
Cleaner right now
- PM2.5
- 11.9 µg/m³
- Main pollutant
- PM2.5
- Source
- Model estimate
- Reading
- Nov 11, 14:00 local
Yemen
AQI 42
Good
Cleaner right now
- PM2.5
- 7 µg/m³
- Main pollutant
- PM2.5
- Source
- Model estimate
- Reading
- Nov 11, 14:00 local
Updated . Lower is better on the US EPA index: 0–50 is Good, above 300 is Hazardous. Measured by Airleaf.
Al Ḩudaydah56Sanaa42
Head to head
Al Ḩudaydah vs Sanaa at a glance
Sanaa is ahead on 4 of 5 measures, and Al Ḩudaydah on 1. The better figure in each row is marked.
| Al Ḩudaydah | Sanaa | |
|---|---|---|
| Air quality nowUS AQI. Lower is better. | 56 | 42 (better) |
| PM2.5Fine particles, µg/m³. | 11.9 | 7 (better) |
| Past week's averageUS AQI, 7 days. | 62 | 38 (better) |
| Tree coverWithin 2 km of the center. | 1.2% | 2.5% (better) |
| Trees still neededTo reach a healthy canopy. | 83.7K (better) | 86.4K |
Air quality today
What is the air like in Al Ḩudaydah and Sanaa right now?
Sanaa has cleaner air than Al Ḩudaydah right now: AQI 42 (Good) against 56 (Moderate). PM2.5 is setting the index in both.
Both readings are model estimates, with no ground station close enough to either.
Al ḨudaydahSanaa
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).
Al Ḩudaydah: Model estimate · no ground station nearby. Data: Open-Meteo / CAMS, US EPA index.
Sanaa: 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, Sanaa averaged AQI 38 against 62, and it was the cleaner of the two on 7 of those days. A single reading can catch a city on a bad afternoon; the week says whether it was the weather or the place.
- Cleaner days
- Al Ḩudaydah0Sanaa7
- Average AQI
- Al Ḩudaydah62Sanaa38
- Worst day, AQI
- Al Ḩudaydah70Sanaa49
The daily numbers (7 days)
| Day | Al Ḩudaydah | Sanaa |
|---|---|---|
| Nov 5 | 66 | 49 |
| Nov 6 | 59 | 48 |
| Nov 7 | 56 | 27 |
| Nov 8 | 58 | 28 |
| Nov 9 | 64 | 31 |
| Nov 10 | 70 | 38 |
| Nov 11 | 59 | 44 |
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 Al Ḩudaydah and Sanaa today?
Al Ḩudaydah (AQI 56, Moderate): Unusually sensitive people should consider limiting long outdoor exertion.
Sanaa (AQI 42, Good): Air quality is satisfactory for everyone.
Exercise outdoors
- Al Ḩudaydah
- Fine for most people; unusually sensitive people should take long or hard exercise easier.
- Sanaa
- A good day to be active outside.
Windows
- Al Ḩudaydah
- Fine to open; close them if you are sensitive to pollution.
- Sanaa
- Open them to air the house.
Masks
- Al Ḩudaydah
- Not needed for most people.
- Sanaa
- Not needed.
Air purifier
- Al Ḩudaydah
- Worth running if you are sensitive.
- Sanaa
- Not needed.
Against everywhere else
How do Al Ḩudaydah and Sanaa compare with the rest of the world?
Right now Al Ḩudaydah's air is cleaner than 54% of the 5,420 places Airleaf tracks, and Sanaa's is cleaner than 71%. Within Yemen, that is 17% and 50% of its 7 measured places.
Cleaner air than…
- Al Ḩudaydah
- Beats 54%
- Sanaa
- Beats 71%
More tree cover than…
- Al Ḩudaydah
- Beats 2%
- Sanaa
- Beats 5%
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.
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.
Al Ḩudaydah
2018: satellite photo from January 2018 of a 5 × 5 km area in the city center.
Sanaa
2017: satellite photo from February 2017 of a 5 × 5 km area in the city center.
Trees
Which has more trees, Al Ḩudaydah or Sanaa?
Sanaa has more tree cover: 2.5% of the land within 2 km of its center against 1.2% around Al Ḩudaydah, or about 7,854 trees against 3,487.
The dark mark is each place's canopy target: 30% of the land, raised where air quality is poor.
| Al Ḩudaydah | Sanaa | |
|---|---|---|
| Trees standingEstimated from the canopy area. | 3.5K | 7.9K (better) |
| Trees still neededTo reach the target. Fewer is better. | 83.7K (better) | 86.4K |
| CO₂ absorbed each yearBy the trees already standing. | 76.7K kg | 173K 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
Al Ḩudaydah vs Sanaa: your questions answered
Is Sanaa cleaner than Al Ḩudaydah?
On air quality, yes, right now: Sanaa reads AQI 42 against 56, a gap of 14 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, Sanaa averaged AQI 38 against 62, and it was the cleaner of the two on 7 of those days.
Is it safe to exercise outdoors in Al Ḩudaydah and Sanaa today?
In Al Ḩudaydah, at AQI 56: Unusually sensitive people should consider limiting long outdoor exertion. In Sanaa, at AQI 42: Air quality is satisfactory for everyone.
Which has more trees, Al Ḩudaydah or Sanaa?
Sanaa has more tree cover: 2.5% of the land within 2 km of its center against 1.2% around Al Ḩudaydah, or about 7,854 trees against 3,487. Both figures describe the same-sized circle of ground around each center, not the whole municipality.
How many more trees do Al Ḩudaydah and Sanaa need?
Al Ḩudaydah needs about 83,692 more to reach its canopy target of 30%, and Sanaa about 86,394 to reach 30%. The target starts at 30% of the land and rises where air quality is poor.
Are Al Ḩudaydah and Sanaa 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 Al Ḩudaydah vs Sanaa 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 (Sep 18, 2026 and Sep 16, 2026), and the forest figures are published yearly.
Keep going
Compare them with somewhere else
Build your own
Compare Al Ḩudaydah with somewhere else
This place
Al Ḩudaydah