Fig. 3

Relative differences in spatial resolution of trace gas measurements (e.g., NO₂) from satellite-based measurements over Ottawa, Canada. Rectangles show the minimum sizes areas covered (pixel size) with three generations of satellites. The blue square corresponds to the less than daily observation frequency of GOME 2. The green square, the daily frequency OMI measurements and, the daylight, hourly frequency of TEMPO (yellow square). The new TEMPO satellite will be capable of collecting data in the ultraviolet and visible wavelengths at approximately 2 km × 5 km spatial resolution. Once in operation TEMPO will produce data for approximately 2.5 million grid cells every daylight hour, equivalent to 1 terabyte of data daily