Air pollution is one of the current major environmental issues affecting human health at the global scale, therefore monitoring air pollution in urban and suburban areas is of great societal importance. The monitoring of air quality at urban scales is currently based on telemetric in-situ networks, which provide continuous observations with high accuracy of a number of relevant air pollutants but have limited representativeness due to the relatively small number of measurement sites.
Air quality satellite observations has resolution values good enough to resolve the spatial and temporal variability of trace gases such as NO2 over regions of the world without sources, e.g. the oceans. However they fail in capturing the variability over most landmasses, especially over urban and complex (e.g.mountainous) terrains.
Ground-based imaging DOAS in downward looking mode can represent a step forward for air quality monitoring in terms of spatial and temporal resolution but is rather seldom simply for the fact that a significantly elevated platform is needed for this purpose. Such a unique situation is present in Innsbruck with the Hafelekar station located at about 1800m above the city with little horizontal distance.
The KARLOS (HafeleKAR Line Of Sight AQ monitoring) project aims to develop a mountain top imaging DOAS overlooking the city of Innsbruck with the following purposes:
- Demonstrate the capabilities and test the performance of the prototype
- Monitor the air quality in and around Innsbruck at high temporal and spatial resolution
- Assess the options for a high resolution air quality retrieval system combining measurements and model calculations