What is the difference in exposure to outdoor air pollution in urban areas between Sierra Leone and Yemen?

2.53 micrograms per cubic meter, with Sierra Leone ahead.

How many years of comparable data are there for Sierra Leone and Yemen?

14 years are reported by both, from 2010 to 2023.

Where does this data come from?

World Health Organization – processed by Our World in Data, published as Exposure to outdoor air pollution in urban areas. Statizoid refreshes it automatically from the source and publishes the full history for both places.

Sierra Leone vs Yemen: Exposure to outdoor air pollution in urban areas

Sierra Leone

36.9 micrograms per cubic meter

in 2023

Yemen

34.37 micrograms per cubic meter

in 2023

Sierra Leone rank

23rd

Yemen rank

26th

Exposure to outdoor air pollution in urban areas over time

Sierra Leone
Yemen

How they compare

Sierra Leone currently reports 36.9 micrograms per cubic meter against 34.37 micrograms per cubic meter in Yemen, a difference of 2.53 micrograms per cubic meter.

That makes Sierra Leone's figure about 1.1 times Yemen's.

The two have swapped places 5 times across 14 shared years of data; in 2010 it was Yemen ahead.

Sierra Leone ranks 23rd and Yemen ranks 26th of 226 countries.

Across the 2 decades both report, Sierra Leone averaged higher in 1 and Yemen in 1.

Head to head by decade

Decade	Sierra Leone	Yemen	Difference	Ahead
2010s	35.23 micrograms per cubic meter	36.64 micrograms per cubic meter	1.42 micrograms per cubic meter	Yemen
2020s	35.75 micrograms per cubic meter	35.64 micrograms per cubic meter	0.11 micrograms per cubic meter	Sierra Leone

Averages of every year both report within each decade.

Frequently asked questions

Which has higher exposure to outdoor air pollution in urban areas, Sierra Leone or Yemen?: Sierra Leone, at 36.9 micrograms per cubic meter against 34.37 micrograms per cubic meter in Yemen as of 2023.
What is the difference in exposure to outdoor air pollution in urban areas between Sierra Leone and Yemen?: 2.53 micrograms per cubic meter, with Sierra Leone ahead.
How many years of comparable data are there for Sierra Leone and Yemen?: 14 years are reported by both, from 2010 to 2023.
How do Sierra Leone and Yemen rank globally for exposure to outdoor air pollution in urban areas?: Sierra Leone ranks 23rd and Yemen ranks 26th of 226 countries.
Where does this data come from?: World Health Organization – processed by Our World in Data, published as Exposure to outdoor air pollution in urban areas. Statizoid refreshes it automatically from the source and publishes the full history for both places.

Individual pages

Share, cite or embed this page

Cite this page

Sierra Leone vs Yemen: Exposure to outdoor air pollution in urban areas. Statizoid, drawing on World Health Organization – processed by Our World in Data. Retrieved 10 September 2026, from https://environment.statizoid.com/compare/exposure-to-outdoor-air-pollution-in-urban-areas/sierra-leone/yemen-rep/

Embed or link this data

Paste this into a page to link back to these figures. The data itself is free to reuse under CC BY 4.0 (Our World in Data); please keep the attribution.

<a href="https://environment.statizoid.com/compare/exposure-to-outdoor-air-pollution-in-urban-areas/sierra-leone/yemen-rep/">Sierra Leone vs Yemen: Exposure to outdoor air pollution in urban areas</a> — Statizoid

About this data

Indicator: Exposure to outdoor air pollution in urban areas
Unit: micrograms per cubic meter
Source: World Health Organization – processed by Our World in Data
Licence: CC BY 4.0 (Our World in Data)
Coverage: 226 places, 3,156 data points, 2010–2023
Last refreshed: 28 August 2026

Annual mean levels of fine particulate matter (population-weighted), by location (micrograms per cubic meter).