{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T06:12:08Z","timestamp":1776147128712,"version":"3.50.1"},"reference-count":49,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2024,3,26]],"date-time":"2024-03-26T00:00:00Z","timestamp":1711411200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Government of Canada"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Cities are important sources of anthropogenic methane emissions. Municipal governments can play a role in reducing those emissions to support climate change mitigation, but they need information on the emission rate to contextualize mitigation actions and track progress. Herein, we examine the application of satellite data from the TROPOspheric Monitoring Instrument (TROPOMI) to estimate city-level methane emission rates in a case study of the City of Calgary, Alberta, Canada. Due to low and variable annual observational coverage, we integrated valid TROPOMI observations over three years (2020\u20132022) and used mass balance modeling to derive a long-term mean estimate of the emission rate. The resulting column-mean dry-air mole fraction (XCH4) enhancement over Calgary was small (4.7 ppb), but within the city boundaries, we identified local hot spots in the vicinity of known emission sources (wastewater treatment facilities and landfills). The city-level emission estimate from mass balance was 215.4 \u00b1 132.8 t CH4\/d. This estimate is approximately four times larger than estimates from Canada\u2019s gridded National Inventory Report of anthropogenic CH4 emissions and six times larger than the Emissions Database for Global Atmospheric Research (EDGAR v8.0). We note that valid TROPOMI observations are more common in warmer months and occur during a narrow daily overpass time slot over Calgary. The limited valid observations in combination with the constrained temporal observational coverage may bias the emission estimate. Overall, the findings from this case study highlight an approach to derive a screening-level estimate of city-level methane emission rates using TROPOMI data in settings with low observational coverage.<\/jats:p>","DOI":"10.3390\/rs16071149","type":"journal-article","created":{"date-parts":[[2024,3,26]],"date-time":"2024-03-26T11:05:33Z","timestamp":1711451133000},"page":"1149","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Satellite-Derived Estimate of City-Level Methane Emissions from Calgary, Alberta, Canada"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9364-116X","authenticated-orcid":false,"given":"Zhenyu","family":"Xing","sequence":"first","affiliation":[{"name":"Centre for Smart Emissions Sensing Technologies, University of Calgary, Calgary, AB T2N 1N4, Canada"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0489-9263","authenticated-orcid":false,"given":"Thomas E.","family":"Barchyn","sequence":"additional","affiliation":[{"name":"Centre for Smart Emissions Sensing Technologies, University of Calgary, Calgary, AB T2N 1N4, Canada"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-9731-2003","authenticated-orcid":false,"given":"Coleman","family":"Vollrath","sequence":"additional","affiliation":[{"name":"Centre for Smart Emissions Sensing Technologies, University of Calgary, Calgary, AB T2N 1N4, Canada"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9730-4953","authenticated-orcid":false,"given":"Mozhou","family":"Gao","sequence":"additional","affiliation":[{"name":"Centre for Smart Emissions Sensing Technologies, University of Calgary, Calgary, AB T2N 1N4, Canada"},{"name":"Sensorup Inc., Calgary, AB T2G 1S5, Canada"}]},{"given":"Chris","family":"Hugenholtz","sequence":"additional","affiliation":[{"name":"Centre for Smart Emissions Sensing Technologies, University of Calgary, Calgary, AB T2N 1N4, Canada"}]}],"member":"1968","published-online":{"date-parts":[[2024,3,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1323","DOI":"10.1126\/science.1240162","article-title":"What role for short-lived climate pollutants in mitigation policy?","volume":"342","author":"Shoemaker","year":"2013","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"318","DOI":"10.1029\/2018GB006009","article-title":"Very strong atmospheric CH4 growth in the 4 years 2014\u20132017: Implications for the Paris Agreement","volume":"33","author":"Nisbet","year":"2019","journal-title":"Glob. 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