The global coronavirus pandemic is having a devastating effect on economies worldwide. However, one of the few positive consequences of travel restrictions and industrial downturn has been a temporary reduction in air pollution. This has made skies cleaner and clearer.
In Kenya’s capital, Nairobi, residents have documented this, reporting that they can now see two prominent mountains – Mount Kenya and Mount Kilimanjaro – from the city. It’s a view they haven’t enjoyed for decades.
Similar examples have been seen in other cities around the world where short-term visibility – our ability to see blue skies – has improved due to the coronavirus lockdown effect.
So why have Mount Kenya and Mount Kilimanjaro not been seen for years? This is because visibility is mainly influenced by small airborne particles, often called particulate matter. These are generated through anthropogenic causes – such as traffic emission, power plants, factories, and crop burning – or natural causes – such as forest-fires, sea salt, dust, and volcanic eruptions. The particles scatter sunlight, thereby reducing visibility. So the more particles, the more pollution.
The evidence shows that the air pollution levels in Nairobi, as with other East African urban areas, are currently at unhealthy levels. But there are very few studies and a lack of systematic and regulatory grade measurements of air pollution in East African cities. Read more…