The blanket of smog that covered Athens yesterday had more to do with abrupt changes in the weather rather than any increase in pollution levels, which were actually very low, scientists told Kathimerini yesterday. The low temperatures that hit Athens recently had caused a blanket of cold air to form over the city. However, the warmer temperatures and sunshine of the last two days trapped the colder blanket of air, and the pollution it contained, at a low level, which caused the foggy feel to the city yesterday, according to Giorgos Kallos, an associate professor at Athens University. The situation was made worse by the fact that winds were too light to disperse the smog. Despite the atmosphere appearing dirty, the Environment Ministry said that pollution levels were well below hazardous levels. Ozone levels were recorded at 66 micrograms per cubic meter yesterday – the danger level is 180.