Ghana's Environmental Protection Authority (EPA) has joined forces with Columbia University. They will now map air pollution across the entire country. This project will track tiny particles, called PM2.5, which are very bad for health. The data will go back to the year 2005.
This partnership addresses a major data gap. For years, Ghana has lacked information on air quality in many areas. This made it hard to understand the true scale of pollution. The new mapping project will show pollution levels everywhere, even places without any air quality monitors. Air pollution leads to about 32,000 deaths in Ghana each year. The World Bank reports it costs the country roughly GHS $7.3 billion annually. This is about 4.5 percent of Ghana's total economic output.
The initiative is vital for Ghana's economic and health policy. Air pollution drains the economy and strains the healthcare system. Previous efforts to curb pollution have been hampered by poor data. Selina Amoah, Head of Air Quality at the EPA, stated that current monitoring shows pollution often exceeds national standards. However, the lack of widespread data made it difficult to prove the effectiveness of policies.
The core tool is called GRASP, the Gridded Africa Surface Pollution dataset. Dr. Daniel Westervelt and his team at Columbia University built GRASP. It uses satellite information from NASA and ground sensor readings. Machine learning then creates a complete picture of air quality for every region. This covers the entire country from 2005 to 2024. The data will be updated regularly and is available online for free. Desmond Appiah of the Clean Air Fund highlighted that low data collection in Africa hinders policymaking. He also stressed that air quality is a shared issue across borders.
A key test for GRASP was evaluating Ghana's emissions levy. This fee was added to vehicle owners' costs in February 2024 to reduce pollution. However, the levy was cancelled soon after. The GRASP analysis showed no significant drop in PM2.5 levels during the levy's short lifespan. Dr. Westervelt noted that for such policies to work, Ghana needs better public transport and to address poverty. He suggested more practical steps like limiting old vehicle imports and supporting cleaner cooking fuels. These are major sources of PM2.5 pollution in Ghana.