{"id":149,"date":"2024-05-02T07:49:04","date_gmt":"2024-05-02T06:49:04","guid":{"rendered":"https:\/\/blog.fmi.fi\/coe-inverse\/?p=149"},"modified":"2026-01-29T05:04:40","modified_gmt":"2026-01-29T05:04:40","slug":"analyzing-nitrogen-dioxide-to-nitrogen-oxide-scaling-factors-for-data-driven-satellite-based-emission-estimation-methods","status":"publish","type":"post","link":"https:\/\/blog.fmi.fi\/coe-inverse\/?p=149","title":{"rendered":"Analyzing nitrogen dioxide to nitrogen oxide scaling factors for data-driven satellite-based emission estimation methods"},"content":{"rendered":"\n<p><strong>Highlights<\/strong><\/p>\n\n\n\n<ul>\n<li>NO<sub>2<\/sub> to NO<sub>x<\/sub> scaling factors calculated from the MicroHH large-eddy simulations.<\/li>\n\n\n\n<li>Optimal scaling factors depend on the emission inversion method.<\/li>\n\n\n\n<li>Scaling factors applied to derive NO<sub>x<\/sub> emissions from S5P\/TROPOMI NO<sub>2<\/sub> observations.<\/li>\n\n\n\n<li>Optimal scaling factors are substantially higher than the values previously used.<\/li>\n<\/ul>\n\n\n\n<p>We have a <a href=\"https:\/\/doi.org\/10.1016\/j.apr.2024.102171\">new paper<\/a> in Atmospheric Pollution Research!<\/p>\n\n\n\n<p>In this paper, we propose improved nitrogen dioxide (NO<sub>2<\/sub>) to nitrogen oxide (NO<sub>x<\/sub>) scaling factors for several data-driven methods that are used for the estimation of NO<sub>x<\/sub> power plant emissions from satellite observations of NO<sub>2<\/sub>. The scaling factors are deduced from high-resolution simulations of power plant plumes with the MicroHH large-eddy simulation model with a simplified chemistry and then applied to Sentinel-5 Precursor (S5P) TROPOspheric Monitoring Instrument (TROPOMI) NO<sub>2<\/sub> satellite observations over the Matimba\/Medupi power stations in South Africa.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"790\" src=\"https:\/\/blog.fmi.fi\/coe-inverse\/wp-content\/uploads\/2024\/05\/emg_lib_ratio2-1024x790.png\" alt=\"\" class=\"wp-image-150\" srcset=\"https:\/\/blog.fmi.fi\/coe-inverse\/wp-content\/uploads\/2024\/05\/emg_lib_ratio2-1024x790.png 1024w, https:\/\/blog.fmi.fi\/coe-inverse\/wp-content\/uploads\/2024\/05\/emg_lib_ratio2-300x231.png 300w, https:\/\/blog.fmi.fi\/coe-inverse\/wp-content\/uploads\/2024\/05\/emg_lib_ratio2-768x592.png 768w, https:\/\/blog.fmi.fi\/coe-inverse\/wp-content\/uploads\/2024\/05\/emg_lib_ratio2-1200x925.png 1200w, https:\/\/blog.fmi.fi\/coe-inverse\/wp-content\/uploads\/2024\/05\/emg_lib_ratio2.png 1380w\" sizes=\"(max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 1362px) 62vw, 840px\" \/><\/figure>\n\n\n\n<p>In this new paper, we show that due to the non-linear chemistry the optimal NO<sub>2<\/sub> to NO<sub>x<\/sub> scaling factors depend on both the method employed and the specific segments of the plume from which emission estimate is derived. The scaling factors derived from the MicroHH simulations in this study are substantially (more than 50%) higher than the typical values used in the literature with actual NO<sub>2<\/sub> observations. The results highlight the challenge in appropriately accounting for the conversion from NO<sub>2<\/sub> to NO<sub>x<\/sub> when estimating point source emissions from satellite NO<sub>2<\/sub> observations.<\/p>\n\n\n\n<p><strong>Reference<\/strong><\/p>\n\n\n\n<p class=\"has-small-font-size\">Janne Hakkarainen, Gerrit Kuhlmann, Erik Koene, Diego Santaren, Sandro Meier, Maarten C. Krol, Bart J.H. van Stratum, Iolanda Ialongo, Fr\u00e9d\u00e9ric Chevallier, Johanna Tamminen, Dominik Brunner, Gr\u00e9goire Broquet,: Analyzing nitrogen dioxide to nitrogen oxide scaling factors for data-driven satellite-based emission estimation methods: a case study of Matimba\/Medupi power stations in South Africa, Atmospheric Pollution Research, Volume 15, Issue 7,\u00a0<a href=\"https:\/\/doi.org\/10.1016\/j.apr.2024.102171\">https:\/\/doi.org\/10.1016\/j.apr.2024.102171<\/a>, 2024.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Highlights We have a new paper in Atmospheric Pollution Research! In this paper, we propose improved nitrogen dioxide (NO2) to nitrogen oxide (NOx) scaling factors for several data-driven methods that are used for the estimation of NOx power plant emissions from satellite observations of NO2. The scaling factors are deduced from high-resolution simulations of power &hellip; <a href=\"https:\/\/blog.fmi.fi\/coe-inverse\/?p=149\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Analyzing nitrogen dioxide to nitrogen oxide scaling factors for data-driven satellite-based emission estimation methods&#8221;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"_links":{"self":[{"href":"https:\/\/blog.fmi.fi\/coe-inverse\/index.php?rest_route=\/wp\/v2\/posts\/149"}],"collection":[{"href":"https:\/\/blog.fmi.fi\/coe-inverse\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.fmi.fi\/coe-inverse\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.fmi.fi\/coe-inverse\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.fmi.fi\/coe-inverse\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=149"}],"version-history":[{"count":1,"href":"https:\/\/blog.fmi.fi\/coe-inverse\/index.php?rest_route=\/wp\/v2\/posts\/149\/revisions"}],"predecessor-version":[{"id":151,"href":"https:\/\/blog.fmi.fi\/coe-inverse\/index.php?rest_route=\/wp\/v2\/posts\/149\/revisions\/151"}],"wp:attachment":[{"href":"https:\/\/blog.fmi.fi\/coe-inverse\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=149"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.fmi.fi\/coe-inverse\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=149"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.fmi.fi\/coe-inverse\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=149"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}