ClearfLo has six overarching scientific aims which are to:
• Establish an infrastructure to measure meteorology, gaseous composition and particulate loading of London’s urban atmosphere at both street level and elevated sites.
• Develop a climatology of London’s urban atmosphere in order to determine the relationships between surface meteorology, gaseous composition and particulates at a rural location, a city background site (away from local traffic sources) and a city street site (close to local traffic sources) through the full range of seasonal cycles.
• Determine the meteorological processes that control the heat content, mixing properties and depth of London’s urban boundary layer, especially the night-time boundary layer, and place them in the mesoscale context, including the prevalence of sea breezes.
• Determine the chemical processes that control the loading of O3 and NO2 in London’s urban atmosphere, particularly the role of biogenic emissions and the role of nitrates in night-time chemistry, and place the urban concentrations into the synoptic context.
• Determine the chemical and physical processes that control the size and number distribution of particulate matter in London’s urban atmosphere, and identify their chemical sources, and place the urban characteristics into the synoptic context of the background.
• Evaluate the strengths and weaknesses of a current air quality model.