Limassol (pop. 154,000) is a port city located on the south coast of Cyprus, the second biggest urban area of the island and hosts the island’s principal port. It is situated 40 km west of the largest industrial area and fossil fuel power plants. Limassol is the most polluted city in Cyprus, frequently exceeding the legislated standards for particulate matter.

The Cyprus Atmospheric Observatory Limassol port station (CAO-LIM) was launched in early 2025 as part of the Horizon EU Net4Cities project. Its strategic seaside position, located right on the Limassol port’s wave breaker (coordinates: 34.6445° N, 33.01633° E), enables continuous monitoring of air pollution emitted from ships and port operations. Ports are recognized as major contributors to local air pollution and public health risks, including elevated levels of NO₂ and PM. CAO-LIM is expected to fill critical data gaps by quantifying shipping-related emissions directly at the source.

The CAO-LIM station comprises two stacked containers. The upper container houses sampling instruments for both particulate and gaseous pollutants, while the lower container serves as a storage facility.