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<p>Satellite observations of the high-resolution TROPOspheric Monitoring Instrument (TROPOMI) on Sentinel-5 Precursor can be used to observe nitrogen dioxide (NO<span class="inline-formula">₂</span>) at city scales to quantify short time variability of nitrogen oxide (NO<span class="inline-formula">_<i>x</i></span>) emissions and lifetimes on a daily and seasonal basis. In this study, 2 years of TROPOMI tropospheric NO<span class="inline-formula">₂</span> columns, having a spatial resolution of up to 3.5 <span class="inline-formula">km</span> <span class="inline-formula">×</span> 5.5 <span class="inline-formula">km</span>, have been analyzed together with wind and ozone data. NO<span class="inline-formula">_<i>x</i></span> lifetimes and emission fluxes are estimated for 50 different NO<span class="inline-formula">_<i>x</i></span> sources comprising cities, isolated power plants, industrial regions, oil fields, and regions with a mix of sources distributed around the world. The retrieved NO<span class="inline-formula">_<i>x</i></span> emissions are in agreement with other TROPOMI-based estimates and reproduce the variability seen in power plant stack measurements but are in general lower than the analyzed stack measurements and emission inventory results. Separation into seasons shows a clear seasonal dependence of NO<span class="inline-formula">_<i>x</i></span> emissions with in general the highest emissions during winter, except for isolated power plants and especially sources in hot desert climates, where the opposite is found. The NO<span class="inline-formula">_<i>x</i></span> lifetime shows a systematic latitudinal dependence with an increase in lifetime from 2 to 8 h with latitude but only a weak seasonal dependence. For most of the 50 sources including the city of Wuhan in China, a clear weekly pattern of NO<span class="inline-formula">_<i>x</i></span> emissions is found, with weekend-to-weekday ratios of up to 0.5 but with a high variability for the different locations. During the Covid-19 lockdown period in 2020, strong reductions in the NO<span class="inline-formula">_<i>x</i></span> emissions were observed for New Delhi, Buenos Aires, and Madrid.</p>