A fog study was implemented by the Alberta Oil Sands Environmental Research Program (AOSERP) during 1977-1978 to provide more detailed observations of fog occurrences, especially during the winter when the possibility of ice fog exists. The objectives of the study are to: 1. Assemble and collate the AOSERP fog information together with the relevant meteorological data and synoptic weather maps; 2. Analyze the relationship between the occurrence of fog with the meteorological conditions; and 3. Evaluate the air quality during the fog episodes.