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This paper discusses the findings of the first car MAX-DOAS (multi-axis differential optical absorption spectroscopy) field campaign (300 km long) along the National Highway-05 (N5-Highway) of Pakistan conducted on 13 and 14 November, 2012. The main objective of the field campaign was to assess the spatial distribution of tropospheric nitrogen dioxide (NO
2) columns and corresponding concentrations along the N5-Highway from Islamabad to Lahore. Source identification of NO
2 revealed that the concentrations were higher within major cities along the highway. The highest NO
2 vertical column densities (NO
2 VCDs) were found around two major cities of Rawalpindi and Lahore. This study also presents a comparison of NO
2 VCDs measured by the ozone monitoring instrument (OMI) and car MAX-DOAS observations. The comparison revealed similar spatial distribution of the NO
2 columns with both car MAX-DOAS and satellite observations, but the car MAX-DOAS observations show much more spatial details. Maximum NO
2 VCD retrieved from car MAX-DOAS observations was up to an order of magnitude larger than the OMI observations in urban areas.
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