Articles | Volume 22, issue 16
https://doi.org/10.5194/bg-22-4163-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-22-4163-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Inferring methane emissions from African livestock by fusing drone, tower, and satellite data
Alouette van Hove
CORRESPONDING AUTHOR
Department of Geosciences, University of Oslo (UiO), Oslo, Norway
Kristoffer Aalstad
Department of Geosciences, University of Oslo (UiO), Oslo, Norway
Vibeke Lind
Division of Food Production and Society, Department of Grassland and Livestock, Norwegian Institute of Bioeconomy Research (NIBIO), Tjøtta, Norway
Claudia Arndt
Mazingira Centre, International Livestock Research Institute (ILRI), Nairobi, Kenya
Vincent Odongo
Mazingira Centre, International Livestock Research Institute (ILRI), Nairobi, Kenya
Rodolfo Ceriani
Department of Agricultural and Environmental Sciences, University of Milan (UNIMI), Milan, Italy
Department of Environmental Science and Policy, University of Milan (UNIMI), Milan, Italy
Francesco Fava
Department of Environmental Science and Policy, University of Milan (UNIMI), Milan, Italy
John Hulth
Department of Geosciences, University of Oslo (UiO), Oslo, Norway
Norbert Pirk
Department of Geosciences, University of Oslo (UiO), Oslo, Norway
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Norbert Pirk, Kristoffer Aalstad, Sebastian Westermann, Astrid Vatne, Alouette van Hove, Lena Merete Tallaksen, Massimo Cassiani, and Gabriel Katul
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Anders Lindroth, Norbert Pirk, Ingibjörg S. Jónsdóttir, Christian Stiegler, Leif Klemedtsson, and Mats B. Nilsson
Biogeosciences, 19, 3921–3934, https://doi.org/10.5194/bg-19-3921-2022, https://doi.org/10.5194/bg-19-3921-2022, 2022
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Joel Fiddes, Kristoffer Aalstad, and Michael Lehning
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This study describes and evaluates a new downscaling scheme that addresses the need for hillslope-scale atmospheric forcing time series for modelling the local impact of regional climate change on the land surface in mountain areas. The method has a global scope and is able to generate all model forcing variables required for hydrological and land surface modelling. This is important, as impact models require high-resolution forcings such as those generated here to produce meaningful results.
Esteban Alonso-González, Ethan Gutmann, Kristoffer Aalstad, Abbas Fayad, Marine Bouchet, and Simon Gascoin
Hydrol. Earth Syst. Sci., 25, 4455–4471, https://doi.org/10.5194/hess-25-4455-2021, https://doi.org/10.5194/hess-25-4455-2021, 2021
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Snow water resources represent a key hydrological resource for the Mediterranean regions, where most of the precipitation falls during the winter months. This is the case for Lebanon, where snowpack represents 31 % of the spring flow. We have used models to generate snow information corrected by means of remote sensing snow cover retrievals. Our results highlight the high temporal variability in the snowpack in Lebanon and its sensitivity to further warming caused by its hypsography.
Cited articles
Abichandani, P., Lobo, D., Ford, G., Bucci, D., and Kam, M.: Wind Measurement and Simulation Techniques in Multi-Rotor Small Unmanned Aerial Vehicles, IEEE Access, 8, 54910–54927, https://doi.org/10.1109/ACCESS.2020.2977693, 2020. a
Allen, G., Hollingsworth, P., Kabbabe, K., Pitt, J. R., Mead, M. I., Illingworth, S., Roberts, G., Bourn, M., Shallcross, D. E., and Percival, C. J.: The development and trial of an unmanned aerial system for the measurement of methane flux from landfill and greenhouse gas emission hotspots, Waste Manage., 87, 883–892, https://doi.org/10.1016/j.wasman.2017.12.024, 2019. a, b, c, d
Amon, B., Amon, T., Boxberger, J., and Alt, C.: Emissions of NH3, N2O and CH4 from dairy cows housed in a farmyard manure tying stall (housing, manure storage, manure spreading), Nutr. Cycl. Agroecosys., 60, 103–113, https://doi.org/10.1023/A:1012649028772, 2001. a, b, c
Andersen, T., Vinkovic, K., De Vries, M., Kers, B., Necki, J., Swolkien, J., Roiger, A., Peters, W., and Chen, H.: Quantifying methane emissions from coal mining ventilation shafts using an unmanned aerial vehicle (UAV)-based active AirCore system, Atmospheric Environment: X, 12, 100135, https://doi.org/10.1016/j.aeaoa.2021.100135, 2021. a, b, c, d, e, f
Anderson, G.: Error propagation by the Monte Carlo method in geochemical calculations, Geochim. Cosmoch. Acta, 40, 1533–1538, https://doi.org/10.1016/0016-7037(76)90092-2, 1976. a
Arndt, C., Leytem, A., Hristov, A., Zavala-Araiza, D., Cativiela, J., Conley, S., Daube, C., Faloona, I., and Herndon, S.: Short-term methane emissions from 2 dairy farms in California estimated by different measurement techniques and US Environmental Protection Agency inventory methodology: A case study, J. Dairy Sci., 101, 11461–11479, https://doi.org/10.3168/jds.2017-13881, 2018. a, b, c, d
Bai, M., Velazco, J. I., Coates, T. W., Phillips, F. A., Flesch, T. K., Hill, J., Mayer, D. G., Tomkins, N. W., Hegarty, R. S., and Chen, D.: Beef cattle methane emissions measured with tracer-ratio and inverse dispersion modelling techniques, Atmos. Meas. Tech., 14, 3469–3479, https://doi.org/10.5194/amt-14-3469-2021, 2021. a
Baldwin, R., McLeod, K., Klotz, J., and Heitmann, R.: Rumen Development, Intestinal Growth and Hepatic Metabolism In The Pre- and Postweaning Ruminant, J. Dairy Sci., 87, E55–E65, 2004. a
Banner, K. M., Irvine, K. M., and Rodhouse, T. J.: The use of Bayesian priors in Ecology: The good, the bad and the not great, Methods Ecol. Evol., 11, 882–889, https://doi.org/10.1111/2041-210X.13407, 2020. a
Berliner, L. M.: Physical-statistical modeling in geophysics, J. Geophys. Res., 108, 8776, https://doi.org/10.1029/2002JD002865, 2003. a
Borchardt, J., Gerilowski, K., Krautwurst, S., Bovensmann, H., Thorpe, A. K., Thompson, D. R., Frankenberg, C., Miller, C. E., Duren, R. M., and Burrows, J. P.: Detection and quantification of CH4 plumes using the WFM-DOAS retrieval on AVIRIS-NG hyperspectral data, Atmos. Meas. Tech., 14, 1267–1291, https://doi.org/10.5194/amt-14-1267-2021, 2021. a
Broucek, J.: Production of Methane Emissions from Ruminant Husbandry: A Review, J. Environ. Prot., 05, 1482–1493, https://doi.org/10.4236/jep.2014.515141, 2014. a, b
Brown, L. R., Benner, D. C., Champion, J. P., Devi, V. M., Fejard, L., Gamache, R. R., Gabard, T., Hilico, J. C., Lavorel, B., Loete, M., Mellau, G. C., Nikitin, A., Pine, A. S., Predoi-Cross, A., Rinsland, C. P., Robert, O., Sams, R. L., Smith, M. A., Tashkun, S. A., and Tyuterev, V. G.: Methane line parameters in HITRAN, J. Quant. Spectrosc. Ra., 82, 219–238, https://doi.org/10.1016/S0022-4073(03)00155-9, 2003. a
Burba, G.: Eddy Covariance Method for Scientific, Industrial, Agricultural and Regulatory Applications: A Field Book on Measuring Ecosystem Gas Exchange and Areal Emission Rates, LI-COR Beosciences, https://doi.org/10.13140/RG.2.1.4247.8561, 2013. a
Burgués, J. and Marco, S.: Environmental chemical sensing using small drones: A review, Sci. Total Environ., 748, 141172, https://doi.org/10.1016/j.scitotenv.2020.141172, 2020. a
Busetto, L.: lbusett/prismaread: v1.0.0, Zenodo [code], https://doi.org/10.5281/zenodo.4019081, 2020. a, b
Calder, K. L.: Multiple-source plume models of urban air pollution—their general structure, Atmos. Environ., 11, 403–414, 1977. a
Cambaliza, M. O. L., Shepson, P. B., Caulton, D. R., Stirm, B., Samarov, D., Gurney, K. R., Turnbull, J., Davis, K. J., Possolo, A., Karion, A., Sweeney, C., Moser, B., Hendricks, A., Lauvaux, T., Mays, K., Whetstone, J., Huang, J., Razlivanov, I., Miles, N. L., and Richardson, S. J.: Assessment of uncertainties of an aircraft-based mass balance approach for quantifying urban greenhouse gas emissions, Atmos. Chem. Phys., 14, 9029–9050, https://doi.org/10.5194/acp-14-9029-2014, 2014. a, b, c
Chopin, N.: A sequential particle filter method for static models, Biometrika, 89, 539–552, https://doi.org/10.1093/biomet/89.3.539, 2002. a
Chopin, N. and Papaspiliopoulos, O.: An Introduction to Sequential Monte Carlo, 1st edition 2020 edn., Springer Series in Statistics, Springer Nature, Cham, https://doi.org/10.1007/978-3-030-47845-2, 2020. a, b, c
Crazzolara, C., Ebner, M., Platis, A., Miranda, T., Bange, J., and Junginger, A.: A new multicopter-based unmanned aerial system for pollen and spores collection in the atmospheric boundary layer, Atmos. Meas. Tech., 12, 1581–1598, https://doi.org/10.5194/amt-12-1581-2019, 2019. a
Cusworth, D. H., Bloom, A. A., Ma, S., Miller, C. E., Bowman, K., Yin, Y., Maasakkers, J. D., Zhang, Y., Scarpelli, T. R., Qu, Z., Jacob, D. J., and Worden, J. R.: A Bayesian framework for deriving sector-based methane emissions from top-down fluxes, Communications Earth & Environment, 2, 242, https://doi.org/10.1038/s43247-021-00312-6, 2021. a
Daube, C., Conley, S., Faloona, I. C., Arndt, C., Yacovitch, T. I., Roscioli, J. R., and Herndon, S. C.: Using the tracer flux ratio method with flight measurements to estimate dairy farm CH4 emissions in central California, Atmos. Meas. Tech., 12, 2085–2095, https://doi.org/10.5194/amt-12-2085-2019, 2019. a
Dittmann, M. T., Runge, U., Lang, R. A., Moser, D., Galeffi, C., Kreuzer, M., and Clauss, M.: Methane Emission by Camelids, PLOS ONE, 9, e94363, https://doi.org/10.1371/journal.pone.0094363, 2014. a, b
Dogniaux, M., Maasakkers, J. D., Varon, D. J., and Aben, I.: Report on Landsat 8 and Sentinel-2B observations of the Nord Stream 2 pipeline methane leak, Atmos. Meas. Tech., 17, 2777–2787, https://doi.org/10.5194/amt-17-2777-2024, 2024. a
Doucet, A. and Johansen, A. M.: A tutorial on particle filtering and smoothing: fiteen years later, in: The Oxford handbook of nonlinear filtering, Oxford handbooks in mathematics, edited by: Crisan, D. and Rozovskii, B. Oxford, N.Y, Oxford University Press, 656–705 pp., ISBN 9780199532902, 2009. a
Evangeliou, N., Thompson, R. L., Eckhardt, S., and Stohl, A.: Top-down estimates of black carbon emissions at high latitudes using an atmospheric transport model and a Bayesian inversion framework, Atmos. Chem. Phys., 18, 15307–15327, https://doi.org/10.5194/acp-18-15307-2018, 2018. a
Francis, A., Li, S., Griffiths, C., and Sienz, J.: Gas source localization and mapping with mobile robots: A review, J. Field Robot., 39, 1341–1373, https://doi.org/10.1002/rob.22109, 2022. a
Gavrilova, O., Leip, A., Dong, H., Macdonald, J., Gomez, C., Amon, B., Barahona Rosales, R., Agustin, Del Prado, A., Lima, M., Oyhantcabal, W., Weerden, T., Widiawati, Y., Bannink, A., Beauchemin, K., Clark, H., Leytem, A., Kebreab, E., Ngwabie, N., and Vellinga, T.: Emissions from livestock and manure management, in: 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories, IPCC, 2019. a
Giardino, C., Bresciani, M., Braga, F., Fabbretto, A., Ghirardi, N., Pepe, M., Gianinetto, M., Colombo, R., Cogliati, S., Ghebrehiwot, S., Laanen, M., Peters, S., Schroeder, T., Concha, J. A., and Brando, V. E.: First evaluation of prisma level 1 data for water applications, Sensors (Switzerland), 20, 1–16, https://doi.org/10.3390/s20164553, 2020. a
Gilks, W. R. and Berzuini, C.: Following a Moving Target—Monte Carlo Inference for Dynamic Bayesian Models, J. R. Stat. Soc. B, 63, 127–146, https://doi.org/10.1111/1467-9868.00280, 2001. a
Golston, L. M., Aubut, N. F., Frish, M. B., Yang, S., Talbot, R. W., Gretencord, C., McSpiritt, J., and Zondlo, M. A.: Natural Gas Fugitive Leak Detection Using an Unmanned Aerial Vehicle: Localization and Quantification of Emission Rate, Atmosphere, 9, 333, https://doi.org/10.3390/atmos9090333, 2018. a
Goopy, J., Onyango, A., Dickhoefer, U., and Butterbach-Bahl, K.: A new approach for improving emission factors for enteric methane emissions of cattle in smallholder systems of East Africa – Results for Nyando, Western Kenya, Agricultural Systems, 161, 72–80, https://doi.org/10.1016/j.agsy.2017.12.004, 2018. a
Goopy, J. P., Korir, D., Pelster, D., Ali, A. I. M., Wassie, S. E., Schlecht, E., Dickhoefer, U., Merbold, L., and Butterbach-Bahl, K.: Severe below-maintenance feed intake increases methane yield from enteric fermentation in cattle, Brit. J. Nutr., 123, 1239–1246, https://doi.org/10.1017/S0007114519003350, 2020. a
Gordon, N., Salmond, D., and Smith, A.: Novel approach to nonlinear/non-Gaussian Bayesian state estimation, IEE Proc.-F, 140, 107–113, https://doi.org/10.1049/ip-f-2.1993.0015, 1993. a
Guanter, L., Irakulis-Loitxate, I., Gorroño, J., Sánchez-García, E., Cusworth, D. H., Varon, D. J., Cogliati, S., and Colombo, R.: Mapping methane point emissions with the PRISMA spaceborne imaging spectrometer, Remote Sens. Environ., 265, 112671, https://doi.org/10.1016/j.rse.2021.112671, 2021. a, b
Gurmu, E., Ndung'u, P., Wilkes, A., Getahun, D., Graham, M., Leitner, S., Marquardt, S., Mulat, D., Merbold, L., Worku, T., Kagai, J., and Arndt, C.: Comparison of Tier 1 and 2 methodologies for estimating intake and enteric methane emission factors from smallholder cattle systems in Africa: a case study from Ethiopia, Animal - Open Space, 3, 100064, https://doi.org/10.1016/j.anopes.2024.100064, 2024. a
Hegarty, R.: Applicability of short-term emission measurements for on-farm quantification of enteric methane, Animal, 7, 401–408, https://doi.org/10.1017/S1751731113000839, 2013. a, b
Hutchinson, M., Oh, H., and Chen, W.-H.: A review of source term estimation methods for atmospheric dispersion events using static or mobile sensors, Inform. Fusion, 36, 130–148, https://doi.org/10.1016/j.inffus.2016.11.010, 2017. a
Hutchinson, M., Liu, C., and Chen, W.: Source term estimation of a hazardous airborne release using an unmanned aerial vehicle, J. Field Robot., 36, 797–817, https://doi.org/10.1002/rob.21844, 2019. a, b, c, d
Hutchinson, M., Liu, C., Thomas, P., and Chen, W.-H.: Unmanned Aerial Vehicle-Based Hazardous Materials Response: Information-Theoretic Hazardous Source Search and Reconstruction, IEEE Robot. Autom. Mag., 27, 108–119, https://doi.org/10.1109/MRA.2019.2943006, 2020. a
Jaynes, E.: Probability theory: the logic of science, Cambridge University Press, Cambridge, https://doi.org/10.1017/CBO9780511790423, 2003. a
Korir, D., Eckard, R., Goopy, J., Arndt, C., Merbold, L., and Marquardt, S.: Effects of replacing Brachiaria hay with either Desmodium intortum or dairy concentrate on animal performance and enteric methane emissions of low-yielding dairy cows, Frontiers in Animal Science, 3, 963323, https://doi.org/10.3389/fanim.2022.963323, 2022a. a, b
Korir, D., Marquardt, S., Eckard, R., Sanchez, A., Dickhoefer, U., Merbold, L., Butterbach-Bahl, K., Jones, C., Robertson-Dean, M., and Goopy, J.: Weight gain and enteric methane production of cattle fed on tropical grasses, Anim. Prod. Sci., 63, 120–132, https://doi.org/10.1071/AN21327, 2022b. a
Lan, X., Thoning, K., and Dlugokencky, E.: Trends in globally-averaged CH4, N2O, and SF6 determined from NOAA Global Monitoring Laboratory measurements, Global Monitoring Laboratory (NOAA), https://doi.org/10.15138/P8XG-AA10, 2024. a
Leitner, S. M., Carbonell, V., Mhindu, R. L., Zhu, Y., Mutuo, P., Butterbach-Bahl, K., and Merbold, L.: Greenhouse gas emissions from cattle enclosures in semi-arid sub-Saharan Africa: The case of a rangeland in South-Central Kenya, Agr. Ecosyst. Environ., 367, 108980, https://doi.org/10.1016/j.agee.2024.108980, 2024. a, b
Loisy, A. and Eloy, C.: Searching for a source without gradients: how good is infotaxis and how to beat it, P. Roy. Soc. A-Math. Phy., 478, 20220118, https://doi.org/10.1098/rspa.2022.0118, 2022. a, b
Loizzo, R., Guarini, R., Longo, F., Scopa, T., Formaro, R., Facchinetti, C., and Varacalli, G.: PRISMA: The Italian hyperspectral mission, in: IGARSS 2018–2018 IEEE international geoscience and remote sensing symposium, Valencia, Spain, 22–27 July 2008, pp. 175–178, 2018. a
Moorhead, J. G.: The Near Infrared Absorption Spectrum of Methane, American Physical Society, Phys. Rev., 39, 83–88, https://doi.org/10.1103/PhysRev.39.83, 1932. a
Morales, R., Ravelid, J., Vinkovic, K., Korbeń, P., Tuzson, B., Emmenegger, L., Chen, H., Schmidt, M., Humbel, S., and Brunner, D.: Controlled-release experiment to investigate uncertainties in UAV-based emission quantification for methane point sources, Atmos. Meas. Tech., 15, 2177–2198, https://doi.org/10.5194/amt-15-2177-2022, 2022. a
Mwangi, P. M., Eckard, R., Gluecks, I., Merbold, L., Mulat, D. G., Gakige, J., Pinares-Patino, C. S., and Marquardt, S.: Impact of Haemonchus contortus infection on feed intake, digestion, liveweight gain, and enteric methane emission from Red Maasai and Dorper sheep, Frontiers in Animal Science, 4, 1212194, https://doi.org/10.3389/fanim.2023.1212194, 2023. a, b
Nathan, B. J., Golston, L. M., O'Brien, A. S., Ross, K., Harrison, W. A., Tao, L., Lary, D. J., Johnson, D. R., Covington, A. N., Clark, N. N., and Zondlo, M. A.: Near-Field Characterization of Methane Emission Variability from a Compressor Station Using a Model Aircraft, Environ. Sci. Technol., 49, 7896–7903, https://doi.org/10.1021/acs.est.5b00705, 2015. a
Ndung'u, P. W., Bebe, B. O., Ondiek, J. O., Butterbach-Bahl, K., Merbold, L., and Goopy, J. P.: Improved region-specific emission factors for enteric methane emissions from cattle in smallholder mixed crop: livestock systems of Nandi County, Kenya, Anim. Prod. Sci., 59, 1136, https://doi.org/10.1071/AN17809, 2019. a
Nielsen, M. O., Kiani, A., Tejada, E., Chwalibog, A., and Alstrup, L.: Energy metabolism and methane production in llamas, sheep and goats fed high- and low-quality grass-based diets, Arch. Anim. Nutr., 68, 171–185, https://doi.org/10.1080/1745039X.2014.912039, 2014. a
Pandey, S., Gautam, R., Houweling, S., Van Der Gon, H. D., Sadavarte, P., Borsdorff, T., Hasekamp, O., Landgraf, J., Tol, P., Van Kempen, T., Hoogeveen, R., Van Hees, R., Hamburg, S. P., Maasakkers, J. D., and Aben, I.: Satellite observations reveal extreme methane leakage from a natural gas well blowout, P. Natl. Acad. Sci. USA, 116, 26376–26381, https://doi.org/10.1073/pnas.1908712116, 2019. a, b
Park, M., An, S., Seo, J., and Oh, H.: Autonomous Source Search for UAVs Using Gaussian Mixture Model-Based Infotaxis: Algorithm and Flight Experiments, IEEE T. Aero. Elec. Sys., 57, 4238–4254, https://doi.org/10.1109/TAES.2021.3098132, 2021. a
Pasquill, F.: The Estimation of the Dispersion of Windborne Material, Meteorol. Mag., 90, 33–40, 1961. a
Pei, Z., Han, G., Mao, H., Chen, C., Shi, T., Yang, K., Ma, X., and Gong, W.: Improving quantification of methane point source emissions from imaging spectroscopy, Remote Sens. Environ., 295, 113652, https://doi.org/10.1016/j.rse.2023.113652, 2023. a
Pinares-Patiño, C. S., Ulyatt, M. J., Waghorn, G. C., Lassey, K. R., Barry, T. N., Holmes, C. W., and Johnson, D. E.: Methane emission by alpaca and sheep fed on lucerne hay or grazed on pastures of perennial ryegrass/white clover or birdsfoot trefoil, J. Agr. Sci., 140, 215–226, https://doi.org/10.1017/S002185960300306X, 2003. a
Pirk, N., Aalstad, K., Westermann, S., Vatne, A., van Hove, A., Tallaksen, L. M., Cassiani, M., and Katul, G.: Inferring surface energy fluxes using drone data assimilation in large eddy simulations, Atmos. Meas. Tech., 15, 7293–7314, https://doi.org/10.5194/amt-15-7293-2022, 2022. a, b
Prather, M. J., Holmes, C. D., and Hsu, J.: Reactive greenhouse gas scenarios: Systematic exploration of uncertainties and the role of atmospheric chemistry, Geophys. Res. Lett., 39, L09803, https://doi.org/10.1029/2012gl051440, 2012. a
Rao, K. S.: Uncertainty Analysis in Atmospheric Dispersion Modeling, Pure Appl. Geophys., 162, 1893–1917, https://doi.org/10.1007/s00024-005-2697-4, 2005. a
Roger, J., Guanter, L., Gorroño, J., and Irakulis-Loitxate, I.: Exploiting the entire near-infrared spectral range to improve the detection of methane plumes with high-resolution imaging spectrometers, Atmos. Meas. Tech., 17, 1333–1346, https://doi.org/10.5194/amt-17-1333-2024, 2024a. a
Roger, J., Irakulis-Loitxate, I., Valverde, A., Gorroño, J., Chabrillat, S., Brell, M., and Guanter, L.: High-Resolution Methane Mapping With the EnMAP Satellite Imaging Spectroscopy Mission, IEEE T. Geosci. Remote, 62, 1–12, https://doi.org/10.1109/TGRS.2024.3352403, 2024b. a
Sanz-Alonso, D.: Inverse problems and data assimilation, 1st ed. edn., vol. 107 of London Mathematical Society student texts; Cambridge University Press, Cambridge, ISBN 9781009414326, 2023. a
Särkkä, S. and Svensson, L.: Bayesian Filtering and Smoothing, 2 edn., Cambridge University Press, https://doi.org/10.1017/9781108917407, 2023. a
Saunois, M., Stavert, A. R., Poulter, B., Bousquet, P., Canadell, J. G., Jackson, R. B., Raymond, P. A., Dlugokencky, E. J., Houweling, S., Patra, P. K., Ciais, P., Arora, V. K., Bastviken, D., Bergamaschi, P., Blake, D. R., Brailsford, G., Bruhwiler, L., Carlson, K. M., Carrol, M., Castaldi, S., Chandra, N., Crevoisier, C., Crill, P. M., Covey, K., Curry, C. L., Etiope, G., Frankenberg, C., Gedney, N., Hegglin, M. I., Höglund-Isaksson, L., Hugelius, G., Ishizawa, M., Ito, A., Janssens-Maenhout, G., Jensen, K. M., Joos, F., Kleinen, T., Krummel, P. B., Langenfelds, R. L., Laruelle, G. G., Liu, L., Machida, T., Maksyutov, S., McDonald, K. C., McNorton, J., Miller, P. A., Melton, J. R., Morino, I., Müller, J., Murguia-Flores, F., Naik, V., Niwa, Y., Noce, S., O'Doherty, S., Parker, R. J., Peng, C., Peng, S., Peters, G. P., Prigent, C., Prinn, R., Ramonet, M., Regnier, P., Riley, W. J., Rosentreter, J. A., Segers, A., Simpson, I. J., Shi, H., Smith, S. J., Steele, L. P., Thornton, B. F., Tian, H., Tohjima, Y., Tubiello, F. N., Tsuruta, A., Viovy, N., Voulgarakis, A., Weber, T. S., van Weele, M., van der Werf, G. R., Weiss, R. F., Worthy, D., Wunch, D., Yin, Y., Yoshida, Y., Zhang, W., Zhang, Z., Zhao, Y., Zheng, B., Zhu, Q., Zhu, Q., and Zhuang, Q.: The Global Methane Budget 2000–2017, Earth Syst. Sci. Data, 12, 1561–1623, https://doi.org/10.5194/essd-12-1561-2020, 2020. a
Scafutto, R. D. P. M., van der Werff, H., Bakker, W. H., van der Meer, F., and de Souza Filho, C. R.: An evaluation of airborne SWIR imaging spectrometers for CH4 mapping: Implications of band positioning, spectral sampling and noise, Int. J. Appl. Earth Obs., 94, 102233, https://doi.org/10.1016/j.jag.2020.102233, 2021. a
Shah, A., Allen, G., Pitt, J. R., Ricketts, H., Williams, P. I., Helmore, J., Finlayson, A., Robinson, R., Kabbabe, K., Hollingsworth, P., Rees-White, T. C., Beaven, R., Scheutz, C., and Bourn, M.: A Near-Field Gaussian Plume Inversion Flux Quantification Method, Applied to Unmanned Aerial Vehicle Sampling, Atmosphere, 10, 396, https://doi.org/10.3390/atmos10070396, 2019. a
Shah, A., Pitt, J. R., Ricketts, H., Leen, J. B., Williams, P. I., Kabbabe, K., Gallagher, M. W., and Allen, G.: Testing the near-field Gaussian plume inversion flux quantification technique using unmanned aerial vehicle sampling, Atmos. Meas. Tech., 13, 1467–1484, https://doi.org/10.5194/amt-13-1467-2020, 2020. a
Student: The probable error of a mean, Biometrika, 6, 1–25, 1908. a
Sutton, O.: The theoretical distribution of airborne pollution from factory chimneys, Q. J. Roy. Meteor. Soc., 73, 426–436, https://doi.org/10.1002/qj.49707331715, 1947. a
Szopa, S., Naik, V., Adhikary, B., Artaxo, P., Berntsen, T., Collins, W., Fuzzi, S., Gallardo, L., Kiendler-Scharr, A., Klimont, Z., Liao, H., Unger, N., , and Zanis, P.: Short-Lived Climate Forcers, in: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Masson-Delmotte, V., Zhai, P., Pirani, A., Connors, S., Péan, C., Berger, S., Caud, N., Chen, Y., Goldfarb, L., Gomis, M., Huang, M., Leitzell, K., Lonnoy, E., Matthews, J., Maycock, T., Waterfield, T., Yelekçi, O., Yu, R., and Zhou, B., Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, https://doi.org/10.1017/9781009157896.008, 817–922, 2021. a
Thompson, R. L., Groot Zwaaftink, C. D., Brunner, D., Tsuruta, A., Aalto, T., Raivonen, M., Crippa, M., Solazzo, E., Guizzardi, D., Regnier, P., and Maisonnier, M.: Effects of extreme meteorological conditions in 2018 on European methane emissions estimated using atmospheric inversions, Philos. T. R. Soc. A, 380, 20200443, https://doi.org/10.1098/rsta.2020.0443, 2022. a
van Hove, A., Aalstad, K., and Pirk, N.: Using reinforcement learning to improve drone-based inference of greenhouse gas fluxes, Nordic Machine Intelligence, 3, 1–6, https://doi.org/10.5617/nmi.9897, 2023. a
van Hove, A., Aalstad, K., and Pirk, N.: Inferring methane emissions from African livestock by fusing drone, tower, and satellite data, Zenodo [data set], https://doi.org/10.5281/zenodo.14214699, 2024a. a, b
van Hove, A., Aalstad, K., and Pirk, N.: Guiding drones by information gain, in: Proceedings of the 5th Northern Lights Deep Learning Conference (NLDL), edited by: Lutchyn, T., Ramírez Rivera, A., and Ricaud, B., vol. 233 of Proceedings of Machine Learning Research, PMLR, https://proceedings.mlr.press/v233/hove24a.html (last access: 11 August 2025), pp. 89–96, 2024b. a, b
van Hove, A.: Methane emission rate Inference of ruminants in Kenya (MIK), GitHub [code], https://github.com/AlouetteUiO/MIK (last access: 11 August 2025), 2024c. a
van Leeuwen, P. J.: Representation errors and retrievals in linear and nonlinear data assimilation, Q. J. Roy. Meteor. Soc., 141, 1612–1623, https://doi.org/10.1002/qj.2464, 2015. a
Varon, D. J., Jacob, D. J., McKeever, J., Jervis, D., Durak, B. O. A., Xia, Y., and Huang, Y.: Quantifying methane point sources from fine-scale satellite observations of atmospheric methane plumes, Atmos. Meas. Tech., 11, 5673–5686, https://doi.org/10.5194/amt-11-5673-2018, 2018. a
Vechi, N. T., Mellqvist, J., and Scheutz, C.: Quantification of methane emissions from cattle farms, using the tracer gas dispersion method, Agr. Ecosyst. Environ., 330, 107885, https://doi.org/10.1016/j.agee.2022.107885, 2022. a
Vergassola, M., Villermaux, E., and Shraiman, B. I.: `Infotaxis' as a strategy for searching without gradients, Nature, 445, 406–409, https://doi.org/10.1038/nature05464, 2007. a
Vergé, C., Dubarry, C., Del Moral, P., and Moulines, E.: On parallel implementation of sequential Monte Carlo methods: the island particle model, Stat. Comput., 25, 243–260, https://doi.org/10.1007/s11222-013-9429-x, 2015. a
Villa, T., Gonzalez, F., Miljievic, B., Ristovski, Z., and Morawska, L.: An Overview of Small Unmanned Aerial Vehicles for Air Quality Measurements: Present Applications and Future Prospectives, Sensors-Basel, 16, 1072, https://doi.org/10.3390/s16071072, 2016. a
Vinković, K., Andersen, T., De Vries, M., Kers, B., Van Heuven, S., Peters, W., Hensen, A., Van Den Bulk, P., and Chen, H.: Evaluating the use of an Unmanned Aerial Vehicle (UAV)-based active AirCore system to quantify methane emissions from dairy cows, Sci. Total Environ., 831, 154898, https://doi.org/10.1016/j.scitotenv.2022.154898, 2022. a, b, c
Western, L. M., Ramsden, A. E., Ganesan, A. L., Boesch, H., Parker, R. J., Scarpelli, T. R., Tunnicliffe, R. L., and Rigby, M.: Estimates of North African Methane Emissions from 2010 to 2017 Using GOSAT Observations, Environ. Sci. Tech. Let., 8, 626–632, https://doi.org/10.1021/acs.estlett.1c00327, 2021. a
Wolz, K., Leitner, S., Merbold, L., Wolf, B., and Mauder, M.: Enteric methane emission estimates for Kenyan cattle in a nighttime enclosure using a backward Lagrangian Stochastic dispersion technique, Theor. Appl. Climatol., 147, 1091–1103, https://doi.org/10.1007/s00704-021-03868-7, 2022. a, b, c, d, e, f, g, h, i
Wratt, D. S., Gimson, N. R., Brailsford, G. W., Lassey, K. R., Bromley, A. M., and Bell, M. J.: Estimating regional methane emissions from agriculture using aircraft measurements of concentration profiles, Atmos. Environ., 35, 497–508, https://doi.org/10.1016/S1352-2310(00)00336-8, 2001. a
Xiao, C., Fu, B., Shui, H., Guo, Z., and Zhu, J.: Detecting the sources of methane emission from oil shale mining and processing using airborne hyperspectral data, Remote Sens.-Basel, 12, 537, https://doi.org/10.3390/rs12030537, 2020. a
Yang, S., Talbot, R. W., Frish, M. B., Golston, L. M., Aubut, N. F., Zondlo, M. A., Gretencord, C., and McSpiritt, J.: Natural Gas Fugitive Leak Detection Using an Unmanned Aerial Vehicle: Measurement System Description and Mass Balance Approach, Atmosphere, 9, 383, https://doi.org/10.3390/atmos9100383, 2018. a, b, c
Short summary
Research on methane emissions from African livestock is limited. We used a probabilistic method fusing drone and flux tower observations with an atmospheric model to estimate emissions from various herds. This approach proved robust under non-stationary wind conditions and effective in estimating emissions as low as 100 g h-1. We also detected spectral anomalies in satellite data associated with the herds. Our method can be used for diverse point sources, thereby improving emission inventories.
Research on methane emissions from African livestock is limited. We used a probabilistic method...
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