Cairo Air Quality
Greater Cairo, Egypt · 21.3M population
Unhealthy for Sensitive Groups
2024 avg
148
Annual AQI
Unhealthy for sensitive groups
45 μg/m³
PM2.5
9× WHO limit
120 μg/m³
PM10
Incl. Khamsin dust
Oct–Nov
Black Cloud
Annual pollution peak
Monthly AQI Pattern
Monthly average AQI — worst in October–November (Black Cloud) and March–April (Khamsin)
Cairo's Major Pollution Sources
The Black Cloud: Annual Crisis
Every October and November, Egyptian farmers burn rice straw in the Nile Delta after harvest. The smoke travels south to Cairo, combining with trapped vehicle exhaust and industrial emissions. The resulting “Black Cloud” (سحابة سوداء) can persist for weeks, reducing visibility and dramatically increasing PM2.5. The phenomenon has been documented since the 1990s and is visible in NASA satellite imagery. Hospital admissions for respiratory conditions spike significantly during Black Cloud episodes. Alternatives to burning (biogas, paper production, animal feed) exist but adoption is slow due to cost.
Khamsin Sandstorms
The Khamsin (Arabic: خمسين, “fifty days”) is a hot, dry, dusty wind from the Sahara that blows across Egypt from March to May. Khamsin events push PM10 above 500 μg/m³ and give the sky a characteristic orange-yellow color. Unlike Dubai's Shamal, the Khamsin is also very hot and dry, causing dehydration and worsening respiratory stress. Khamsin storms occur roughly 50 days per year, hence the name.
Traffic: 21 Million People, Old Vehicles
Greater Cairo is home to 21+ million people and millions of vehicles, many older models with poor emission controls. The ancient informal microbus (microbus) and aging diesel truck fleets are significant contributors. The Cairo Metro and suburban rail provide alternatives for some commuters, but car dependency is still high. The ring roads and Nile bridges see massive daily congestion that generates concentrated local PM2.5 and NO2.
Industrial Zones
Cairo's Shoubra El-Kheima industrial corridor, the Helwan steel complex, and cement factories in the Greater Cairo ring emit significant PM2.5 and SO₂. Egypt's rapid urbanization has left industrial zones within the city boundary as the city expanded around them. Brick kilns on the urban fringe are additional PM sources. Egypt's Environmental Regulation Law sets emission standards, but enforcement varies.
Frequently Asked Questions
What is the Black Cloud phenomenon in Cairo?
The 'Black Cloud' (سحابة سوداء) is an annual air pollution event from October to November. Egyptian farmers burn rice straw in the Nile Delta after harvest — burning is faster and cheaper than removal. Smoke drifts to Cairo, combines with vehicle exhaust and industrial emissions, and creates weeks of toxic haze visible from space. PM2.5 spikes dramatically, and respiratory hospital admissions rise significantly.
Is Cairo the most polluted city in Africa?
Cairo is consistently among the most polluted cities in Africa and the Middle East, with an annual average AQI of ~148 and PM2.5 of ~45 μg/m³ — about 9× the WHO guideline. Cities like Lagos (Nigeria) and Kinshasa (DRC) also face severe pollution. In the Middle East, Tehran (AQI ~135) and Riyadh (~102) also exceed Cairo some years. It depends on the metric — Cairo typically leads on PM2.5 due to the Black Cloud.
How does Cairo compare to Delhi for air quality?
Delhi and Cairo are comparable — both are among the world's most polluted megacities with AQI in the 140–160 range annually. Delhi's problem is more severe in absolute PM2.5 terms (~50+ μg/m³ vs Cairo's ~45 μg/m³). Both cities have vehicle-dominated pollution + agriculture burning events (Delhi: crop stubble fires; Cairo: rice straw Black Cloud) + industry + geography that traps pollution.
What is being done to improve Cairo air quality?
Egypt launched the 'Clean Sky' program providing subsidies to farmers for rice straw alternatives (biogas, animal feed, paper) to reduce Black Cloud burning. Cairo Metro expansions aim to reduce car trips. Vehicle emission testing programs exist but enforcement varies. The 2019 New Administrative Capital project is partly designed to reduce pressure on Cairo's infrastructure — though environmental impact is debated.