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Weekly variations in column NO2. (Top left) TROPOMI NO2 during Mondays. (Bottom left) TROPOMI NO2 during Sundays. (Top right) Weekly variation of TROPOMI NO2 in seven U.S. cities normalized to Mondays; city averages are across a 1° × 1° box centered on the city. (Bottom right) Ratio between Sundays and Mondays.
