Day, D. A., Campuzano-Jost, P., Nault, B. A., Palm, B. B., Hu, W., Guo, H., Wooldridge, P. J., Cohen, R. C., Docherty, K. S., Huffman, J. A., de Sá, S. S., Martin, S. T., and Jimenez, J. L.: A systematic re-evaluation of methods for quantification of bulk particle-phase organic nitrates using real-time aerosol mass spectrometry, Atmos. Meas. Tech., 15, 459–483, https://doi.org/10.5194/amt-15-459-2022, 2022.
DeWitt, H. L., Gasore, J., Rupakheti, M., Potter, K. E., Prinn, R. G., Ndikubwimana, J. D. D., Nkusi, J., and Safari, B.: Seasonal and diurnal variability in
O3, black carbon, and CO measured at the Rwanda Climate Observatory , Atmos. Chem. Phys., 19, 2063–2078, https://doi.org/10.5194/acp-19-2063-2019, 2019.
Dhammapala, R.: Analysis of fine particle pollution data measured at 29 US diplomatic posts worldwide, Atmos. Environ., 213, 367–376, https://doi.org/10.1016/j.atmosenv.2019.05.070, 2019.
Engeln, A. V. and Teixeira, J.: A planetary boundary layer height climatology derived from ECMWF reanalysis data, J. Climate, 26, 6575–6590, https://doi.org/10.1175/JCLI-D-12-00385.1, 2013.
Farmer, D. K., Matsunaga, A., Docherty, K. S., Surratt, J. D., Seinfeld, J. H., Ziemann, P. J., and Jimenez, J. L.: Response of an aerosol mass spectrometer to organonitrates and organosulfates and implications for atmospheric chemistry, P. Natl. Acad. Sci. USA, 107, 6670–6675, https://doi.org/10.1073/pnas.0912340107, 2010.
Fisher, S., Bellinger, D. C., Cropper, M. L., Kumar, P., Binagwaho, A., Koudenoukpo, J. B., Park, Y., Taghian, G., and Landrigan, P. J.: Air pollution and development in Africa: impacts
on health, the economy, and human capital, Lancet Planet. Health, 5, e681–e688, https://doi.org/10.1016/S2542-5196(21)00201-1, 2021.
Gaita, S. M., Boman, J., Gatari, M. J., Pettersson, J. B. C., and Janhäll, S.: Source apportionment and seasonal variation of
PM2.5 in a Sub-Saharan African city: Nairobi, Kenya, Atmos. Chem. Phys., 14, 9977–9991, https://doi.org/10.5194/acp-14-9977-2014, 2014.
Gentner, D. R.: Review of urban secondary organic aerosol formation from gasoline and Diesel motor vehicle emissions, ACSP Publisher, https://doi.org/10.1021/acs.est.6b04509, 2016.
Global Burden of Disease: The State of Air Quality and Health Impacts in Africa, A Report from the State of Global Air Initiative, Boston, MA:Health Effects Institute, GBD, Africa, 2024.
Global Energy Monitor: Worldwide coal plants, 1200,
https://globalenergymonitor.org/projects/global-coal-plant-tracker/tracker/ (last access: 20 November 2024), 2025.
Habineza, T., Presto, A., Gasore, J., Robinson, A., DeWitt H. L., and Croteau, P. L.: Chemical characterization and source apportionment of fine particulate matter in Kigali, Rwanda, using aerosol mass spectrometry, Carnegie Mellon University [data set],
https://kilthub.cmu.edu/articles/dataset/_b_Chemical_characterization_and_source_apportionment_of_fine_particulate_matter_in_Kigali_Rwanda_using_aerosol_mass_spectrometry_b_/30442775 (last access: 11 November 2025), 2025.
He, X., Zheng, X., You, Y., Zhang, S., Zhao, B., Wang, X., Huang, G., Chen, T., Cao, Y., He, L., Chang, X., Wang, S., and Wu, Y.: Comprehensive chemical characterization of gaseous I/SVOC emissions from heavy-duty diesel vehicles using two-dimensional gas chromatography time-of-flight mass spectrometry, Environ. Pollut., 305, https://doi.org/10.1016/j.envpol.2022.119284, 2022.
Health Effects Institute: The State of Air Quality and Health Impacts in Africa, A Report from the State of Global Air Initiative, Health Effects Institute, Boston, MA, Health Effects Institute, Africa, 2022.
Health Effects Institute: The State of Air Quality and Health Impacts in Africa, A Report from the State of Global Air Initiative, Health Effects Institute, Boston, MA, Health Effects Institute, Africa, 2023.
Huffman, J. A., Jayne, J. T., Drewnick, F., Aiken, A. C., Onasch, T., Worsnop, D. R., and Jimenez, J. L.: Design, modeling, optimization, and experimental tests of a particle beam width probe for the aerodyne aerosol mass spectrometer, Aerosol Sci. Tech., 39, 1143–1163, https://doi.org/10.1080/02786820500423782, 2005.
Kalisa, E. and Adams, M.: Population-scale COVID-19 curfew effects on urban black carbon concentrations and sources in Kigali, Rwanda, Urban Clim., 46, https://doi.org/10.1016/j.uclim.2022.101312, 2022.
Kalisa, E., Nagato, E. G., Bizuru, E., Lee, K. C., Tang, N., Pointing, S. B., Hayakawa, K., Archer, S. D. J., and Lacap-Bugler, D. C.: Characterization and risk assessment of atmospheric
PM2.5 and
PM10 particulate-bound PAHs and NPAHs in Rwanda, Central-East Africa, Environ. Sci. Technol., 52, 12179–12187, https://doi.org/10.1021/acs.est.8b03219, 2018.
Kalisa, E., Sudmant, A., Ruberambuga, R., and Bower, J.: Natural experiments in urban air quality: lessons from car-free days and COVID-19 lockdowns in Kigali, Rwanda, Cities Health, https://doi.org/10.1080/23748834.2025.2468017, 2025.
Kigali City: Overview,
https://www.kigalicity.gov.rw/about/overview, last access: 30 July 2025.
Kirago, L., Gustafsson, Ö., Gaita, S. M., Haslett, S. L., Dewitt, H. L., Gasore, J., Potter, K. E., Prinn, R. G., Rupakheti, M., Ndikubwimana, J. D. D., Safari, B., and Andersson, A.: Atmospheric black carbon loadings and sources over Eastern Sub-Saharan Africa are governed by the regional Savanna fires, Environ. Sci. Technol., 56, 15460–15469, https://doi.org/10.1021/acs.est.2c05837, 2022.
Liu, P. S. K., Deng, R., Smith, K. A., Williams, L. R., Jayne, J. T., Canagaratna, M. R., Moore, K., Onasch, T. B., Worsnop, D. R., and Deshler, T.: Transmission efficiency of an aerodynamic focusing lens system: comparison of model calculations and laboratory measurements for the aerodyne aerosol mass spectrometer, Aerosol Sci. Tech., 41, 721–733, https://doi.org/10.1080/02786820701422278, 2007.
Matthew, B. M., Middlebrook, A. M., and Onasch, T. B.: Collection efficiencies in an aerodyne aerosol mass spectrometer as a function of particle phase for laboratory generated aerosols, Aerosol Sci. Tech., 42, 884–898, https://doi.org/10.1080/02786820802356797, 2008.
McFarlane, C., Isevulambire, P. K., Lumbuenamo, R. S., Ndinga, A. M. E., Dhammapala, R., Jin, X., McNeill, V. F., Malings, C., Subramanian, R., and Westervelt, D. M.: First measurements of ambient
PM2.5 in Kinshasa, Democratic Republic of Congo and Brazzaville, Republic of Congo using field-calibrated low-cost sensors, Aerosol Air Qual. Res., 21, https://doi.org/10.4209/aaqr.200619, 2021.
MINEFRA: Republic Of Rwanda Ministry Of Infrastructure Rwanda Energy Policy, Mifrotra, Rwanda, 2015.
MINEFRA: Republic Of Rwanda Ministry Of Infrastructure, Energy Sector Strategic Plan, Guideline No. 12957, 3,1–176, Ministry of infrastructure, Rwanda, 2018a.
MINEFRA: Republic Of Rwanda Ministry Of Infrastructure, Energy Sector Strategic Plan, Ministry of Infrastructure, Rwanda, 2018b.
Mkoma, S. L., Maenhaut, W., Chi, X., Wang, W., and Raes, N.: Characterisation of
PM10 atmospheric aerosols for the wet season 2005 at two sites in East Africa, Atmos. Environ., 43, 631–639, https://doi.org/10.1016/j.atmosenv.2008.10.008, 2009.
Ndamuzi, E., Akimana, R., Gahungu, P., and Bimenyimana, E.: Modeling and characterization of fine particulate matter dynamics in Bujumbura using low-cost sensors, J. Appl. Math. Phys., 12, 256–267, https://doi.org/10.4236/jamp.2024.121020, 2024.
Ng, N. L., Canagaratna, M. R., Jimenez, J. L., Zhang, Q., Ulbrich, I. M., and Worsnop, D. R.: Real-time methods for estimating organic component mass concentrations from aerosol mass spectrometer data, Environ. Sci. Technol., 45, 910–916, https://doi.org/10.1021/es102951k, 2011.
Nicholson, S. E.: Climate and climatic variability of rainfall over eastern Africa, Rev. Geophys., 55, 590–635, https://doi.org/10.1002/2016RG000544, 2017.
NIS Rwanda: Rwanda statistical year book 2021, Rwanda national Institute of statistics, Rwanda, 2021.
Niyibizi, A., Baptiste Nduwayezu, J., Ishimwe, T., and Ngirabakunzi, B.: Quantification of air pollution in Kigali City and its environmental and socio-economic impact in Rwanda, Am. J. Environ. Eng., 5, 106–119, https://doi.org/10.5923/j.ajee.20150504.03, 2015.
Nyeki, S., Li, F., Weingartner, E., Streit, N., Colbeck, I., Gäggeler, H. W., and Baltensperger, U.: The background aerosol size distribution in the free troposphere: an analysis of the annual cycle at a high-alpine site, J. Geophys. Res.-Atmos., 103, 31749–31761, https://doi.org/10.1029/1998JD200029, 1998.
Onyango, S., North, C. M., Ellaithy, H. A., Tumwesigye, P., Kang, C. M., Matthaios, V., Mukama, M., Nambogo, N., Wolfson, J. M., Ferguson, S., Asiimwe, S., Atuyambe, L., Santorino, D., Christiani, D. C., and Koutrakis, P.: Ambient
PM2.5 temporal variation and source apportionment in Mbarara, Uganda, Aerosol Air Qual. Res., 24, https://doi.org/10.4209/aaqr.230203, 2024.
openaq: Explore the data,
https://explore.openaq.org/?parameter=pm25#1/24.6/55.8, last access: 2 January 2025.
Oregon USA WaveMetrics: Igor pro wave matrix,
https://www.wavemetrics.com/downloads/current/Igor%20Pro%209 (last access: 6 November 2024), 2024.
Paatero, P. and Tapper, U.: Positive matrix factorization: a non-negative factor model with optimal utilization of error estimates of data values, Environmetrics, 5, 111–126, https://doi.org/10.1002/env.3170050203, 1994.
REMA: Inventory of Sources of Air Pollution in Rwanda Determination of Future Trends and Development of a National Air Quality Control Strategy, inventory no. 382754, 1–176, Rwanda Environment Management Authority (REMA), Rwanda, 2018.
Republic of Rwanda: Ministerial Guidelines for Clean Cooking Technologies, Ministry of Infrastracture, Rwanda, 2022.
Rwanda Standards Board: Ambient Air quality specification in Rwanda, RS EAC 751:2010,
https://portal.rsb.gov.rw/webstore_preview.php?id=OTY3RkJrTndaM0EzcA (last access: 7 March 2024), 2010.
Rwanda Standards Board: Air quality specification by ciment facory in Rwanda, RS EAC 752:2011,
https://portal.rsb.gov.rw/webstore_preview.php?id=OTY3RkJrTndaM0EzcA (last access: 7 March 2024), 2011.
Sandradewi, J., Prévôt, A. S. H., Szidat, S., Perron, N., Alfarra, M. R., Lanz, V. A., Weingartner, E., and Baltensperger, U. R. S.: Using aerosol light abosrption measurements for the quantitative determination of wood burning and traffic emission contribution to particulate matter, Environ. Sci. Technol., 42, 3316–3323, https://doi.org/10.1021/es702253m, 2008.
Singh, A., Ng'ang'a, D., Gatari, M. J., Kidane, A. W., Alemu, Z. A., Derrick, N., Webster, M. J., Bartington, S. E., Thomas, G. N., Avis, W., and Pope, F. D.: Air quality assessment in three east african cities using calibrated low-cost sensors with a focus on road-based hotspots, Environ. Res. Commun., 3, https://doi.org/10.1088/2515-7620/ac0e0a, 2021.
Sitati, C. N., Oludhe, C., Oyake, L., and Mbandi, A. M.: A street-level assessment of greenhouse gas emissions associated with traffic congestion in the city of Nairobi, Kenya, Clean Air J., 32, https://doi.org/10.17159/caj/2022/32/1.12546, 2022.
Smithsonia Institute: Global Volcanism Program, 2024, Report on Nyiragongo (DR Congo), in: Weekly Volcanic Activity Report, 3–9 July 2024, edited by: Sennert, S., Smithsonian Institution and US Geological Survey,
https://volcano.si.edu/volcanolist_countries.cfm?country=DRC (last access: 7 March 2024), 2025.
STATISTICAL: Rwanda statistical year book 2021, Rwanda national Institute of statistics, Rwanda, 2021.
Subramanian, R., Kagabo, A. S., Baharane, V., Guhirwa, S., Sindayigaya, C., Malings, C., Williams, N. J., Kalisa, E., Li, H., Adams, P., Robinson, A. L., DeWitt, H. L., Gasore, J., and Jaramillo, P.: Air pollution in Kigali, Rwanda: spatial and temporal variability, source contributions, and the impact of car-free Sundays, Clean Air J., 30, 1–15, https://doi.org/10.17159/caj/2020/30/2.8023, 2020.
Taghian, G., Fisher, S., Chiles, T. C., Binagwaho, A., and Landrigan, P. J.: The burden of cardiovascular disease from air pollution in Rwanda, Ann. Glob. Health, 90, https://doi.org/10.5334/aogh.4322, 2024.
Tefera, W., Kumie, A., Berhane, K., Gilliland, F., Lai, A., Sricharoenvech, P., Patz, J., Samet, J., and Schauer, J. J.: Source apportionment of fine organic particulate matter (
PM2.5) in central Addis Ababa, Ethiopia, Int. J. Environ. Res. Public. Health, 18, https://doi.org/10.3390/ijerph182111608, 2021.
Teledyne: User Manual Model T640 PM Mass Monitor, 2016.
The World Bank Group: Climate Change Knowledge Portal For Development Practitioners and Policy Makers,
https://climateknowledgeportal.worldbank.org/country/rwanda/climate-data-historica, last access: 30 July 2025.
Ulbrich, I. M., Canagaratna, M. R., Zhang, Q., Worsnop, D. R., and Jimenez, J. L.: Interpretation of organic components from Positive Matrix Factorization of aerosol mass spectrometric data, Atmos. Chem. Phys., 9, 2891–2918, https://doi.org/10.5194/acp-9-2891-2009, 2009.
UN Environment: Kigali City Air Quality Policy and Regulatory Situational Analysis, A report published by UN Environment in collaboration with Environmental Compliance Institute, 2018.
UN Environment: Kigali City Air Quality Policy and Regulatory Situational Analysis, A report published by UN Environment in collaboration with Environmental Compliance Institute, UN, Kigali City, 2019.
UNFCCC_Rwanda: REPUBLIC OF RWANDA Rwanda's First Biennial Update Report Under the United Nations Framework Convention on Climate Change (UNFCCC), 2021.
Uwimbabazi, P.: An Analysis of Umuganda: the Policy and Practice of Community Work in Rwanda, PhD Thesis, KwaZulu-Natal, 2012.
Werden, B. S., Giordano, M. R., Mahata, K., Islam, M. R., Goetz, J. D., Puppala, S. P., Saikawa, E., Panday, A. K., Yokelson, R. J., Stone, E. A., and DeCarlo, P. F.: Submicron aerosol composition and source contribution across the Kathmandu Valley, Nepal, in winter, ACS Earth Space Chem., 7, 49–68, https://doi.org/10.1021/acsearthspacechem.2c00226, 2023.
World Health Organization (WHO): The Global Health Observatory, Explore a world of health data, Air pollution data port
al
https://www.who.int/data/gho/data/themes/air-pollution, last access: 2 January 2025.
Xu, Q., Wang, S., Jiang, J., Bhattarai, N., Li, X., Chang, X., Qiu, X., Zheng, M., Hua, Y., and Hao, J.: Nitrate dominates the chemical composition of PM2.5 during haze event in Beijing, China, Sci. Total Environ., 689, 1293–1303, https://doi.org/10.1016/j.scitotenv.2019.06.294, 2015.
Zhang, Q., Jimenez, J. L., Canagaratna, M. R., Ulbrich, I. M., Ng, N. L., Worsnop, D. R., and Sun, Y.: Understanding atmospheric organic aerosols via factor analysis of aerosol mass spectrometry: a review, Anal. Bioanal. Chem., 401, 3045–3067, https://doi.org/10.1007/s00216-011-5355-y, 2011.
