About Ritesh Gautam

Ritesh Gautam

Lead Senior Scientist


Areas of expertise:

Satellite remote sensing, atmospheric aerosols, climatology, radiative forcing


Dr. Ritesh Gautam is a Lead Senior Scientist on the MethaneSAT mission at Environmental Defense Fund. At EDF, Dr. Gautam oversees remote sensing projects and scientific studies on characterizing anthropogenic methane emissions using satellite data, in collaboration with academia and other research organizations. Ritesh leads scientific efforts to ensure high quality of MethaneSAT’s and MethaneAIR’s data products in order to effectively quantify methane emissions. His team’s research is focused on the attribution of the various sources, infrastructure and underlying processes linked to emissions in particular from the oil and gas sector globally. Ritesh’s scientific interests also include characterizing climate effects of air pollution derived using long-term satellite remote sensing measurements.


Prior to joining EDF in 2016, he served as a research scientist at NASA Goddard Space Flight Center with Universities Space Research Association, and as a tenured professor at the Indian Institute of Technology (IIT) Bombay. At NASA Goddard, he was a recipient of the Scientific Leadership Award from the Climate and Radiation group as well as GESTAR’s Mission Achievement Award. His research experience spans the last twenty years focusing on satellite remote sensing, methane emissions, aerosols, clouds and cryosphere. He has more than 60 scientific articles published in peer-reviewed literature including several high-impact papers in PNAS, Nature Communications, Science Advances, GRL which have received wide citation record and coverage in media.


PhD degree in Earth System & Geoinformation Sciences from George Mason University, Virginia


Shen, L., Jacob, D. J., Gautam, R., Omara, M., Scarpelli, T. R., Lorente, A., … & Lin, J. (2023). National quantifications of methane emissions from fuel exploitation using high resolution inversions of satellite observations. Nature Communications, 14(1), 4948.

Gautam, R., P.N. Patel, M.K. Singh, T. Liu, L.J. Mickley, H. Jethva, R.S. DeFries, Extreme smog challenge of south Asia intensified by lower tropospheric stability, Geophysical Research Letters 50 (11), e2023GL103105 (2023).

Omara, M., Gautam, R., O’Brien, M. A., Himmelberger, A., Franco, A., Meisenhelder, K., Hauser, G., Lyon, D. R., Chulakadabba, A., Miller, C. C., Franklin, J., Wofsy, S. C., and Hamburg, S. P.: Developing a spatially explicit global oil and gas infrastructure database for characterizing methane emission sources at high resolution, Earth Syst. Sci. Data, 15, 3761–3790, https://doi.org/10.5194/essd-15-3761-2023, 2023.

Chan Miller, C., Roche, S., Wilzewksi, J. S., Liu, X., Chance, K., Souri, A. H., Conway, E., Luo, B., Samra,J., Hawthorne, J., Sun, K., Staebell, C., Chulakadabba, A., Sargent, M., Benmergui, J. S., Franklin, J. E., Daube, B. C., Li, Y., Laughner, J. L., Baier, B. C., Gautam, R., Omara, M., and Wofsy, S. C.: Methane retrieval from MethaneAIR using the CO2 Proxy Approach: A demonstration for the upcoming MethaneSAT mission, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2023-1962, 2023.

Chulakadabba, A., Sargent, M., Lauvaux, T., Benmergui, J. S., Franklin, J. E., Chan Miller, C., Wilzewski, J. S., Roche, S., Conway, E., Souri, A. H., Sun, K., Luo, B., Hawthrone, J., Samra, J., Daube, B. C., Liu, X., Chance, K. V., Li, Y., Gautam, R., Omara, M., Rutherford, J. S., Sherwin, E. D., Brandt, A., and Wofsy, S. C.: Methane Point Source Quantification Using MethaneAIR: A New Airborne Imaging Spectrometer, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2023-822, 2023.

Varon, D. J., Jacob, D. J., Hmiel, B., Gautam, R., Lyon, D. R., Omara, M., Sulprizio, M., Shen, L., Pendergrass, D., Nesser, H., Qu, Z., Barkley, Z. R., Miles, N. L., Richardson, S. J., Davis, K. J., Pandey, S., Lu, X., Lorente, A., Borsdorff, T., Maasakkers, J. D., and Aben, I.: Continuous weekly monitoring of methane emissions from the Permian Basin by inversion of TROPOMI satellite observations, Atmos. Chem. Phys., 23, 7503–7520, https://doi.org/10.5194/acp-23-7503-2023, 2023.

Chen, Z., Jacob, D. J., Gautam, R., Omara, M., Stavins, R. N., Stowe, R. C., Nesser, H., Sulprizio, M. P., Lorente, A., Varon, D. J., Lu, X., Shen, L., Qu, Z., Pendergrass, D. C., and Hancock, S.: Satellite quantification of methane emissions and oil–gas methane intensities from individual countries in the Middle East and North Africa: implications for climate action, Atmos. Chem. Phys., 23, 5945–5967, https://doi.org/10.5194/acp-23-5945-2023, 2023.

Patel, P., Jiang, J., Gautam, R., Gadhavi, H., Kalashnikova, O., Garay, M., Gao, L., Xu, F., and Omar, A.: Resolving Vertical Profile of Cloud Condensation Nuclei Concentrations from Spaceborne Lidar Measurements, Atmos. Chem. Phys. Discuss. https://doi.org/10.5194/acp-2022-547, (2022)

Singh, M. K., & Gautam, R. Developing a long-term high-resolution winter fog climatology over south Asia using satellite observations from 2002 to 2020. Remote Sensing of Environment, 279, 113128 (2022).

Liu, T., L. J. Mickley, P. N. Patel, R. Gautam, M. Jain, S. Singh, B. Singh, R. S. DeFries, M. E. Marlier. Cascading delays in the monsoon rice growing season and post-monsoon agricultural fires likely exacerbate air pollution in North India, Journal of Geophysical Research – Atmospheres, 127, e2022JD036790. https://doi.org/10.1029/2022JD036790 (2022).

Shen, L., Gautam, R., Omara, M., Zavala-Araiza, D., Maasakkers, J. D., Scarpelli, T. R., Lorente, A., Lyon, D., Sheng, J., Varon, D. J., Nesser, H., Qu, Z., Lu, X., Sulprizio, M. P., Hamburg, S. P., and Jacob, D. J.: Satellite quantification of oil and natural gas methane emissions in the US and Canada including contributions from individual basins, Atmos. Chem. Phys., 22, 11203–11215, (2022).

Fadnavis, S., Roxy, M.K., Griessbach, S., Heinold, B., Kaskaoutis, D.G., and Gautam, R. Editorial: Impact of the COVID19 lockdown on the atmosphere. Front. Environ. Sci. 10:1034007. doi: 10.3389/fenvs.2022.1034007 (2022).

Jacob, D. J., Varon, D. J., Cusworth, D. H., Dennison, P. E., Frankenberg, C., Gautam, R., Guanter, L., Kelley, J., McKeever, J., Ott, L. E., Poulter, B., Qu, Z., Thorpe, A. K., Worden, J. R., and Duren, R. M. Quantifying methane emissions from the global scale down to point sources using satellite observations of atmospheric methane, Atmos. Chem. Phys., 22, 9617–9646 (2022).

Maasakkers, J. D., Omara, M., Gautam, R., Lorente, A., Pandey, S., Tol, P., … & Aben, I. (2022). Reconstructing and quantifying methane emissions from the full duration of a 38-day natural gas well blowout using space-based observations. Remote Sensing of Environment, 270, 112755. Impact factor – 13.8

Lu, X., Jacob, D. J., Wang, H., Maasakkers, J. D., Zhang, Y., Scarpelli, T. R., Shen, L., Qu, Z., Sulprizio, M. P., Nesser, H., Bloom, A. A., Ma, S., Worden, J. R., Fan, S., Parker, R. J., Boesch, H., Gautam, R., Gordon, D., Moran, M. D., Reuland, F., Villasana, C. A. O., and Andrews, A.: Methane emissions in the United States, Canada, and Mexico: evaluation of national methane emission inventories and 2010–2017 sectoral trends by inverse analysis of in situ (GLOBALVIEWplus CH4 ObsPack) and satellite (GOSAT) atmospheric observations, Atmos. Chem. Phys., 22, 395–418 (2022).

Liu, T., L.J. Mickley, R. Gautam, M.K. Singh, R.S. DeFries, and M.E. Marlier. Detection of delay in post-monsoon agricultural burning across Punjab, India: potential drivers and consequences for air quality. Environmental Research Letters, 16 (1), 014014 (2021).

Gatebe, C. K., Jethva, H., Gautam, R., Poudyal, R., and Várnai, T.: A new measurement approach for validating satellite-based above cloud aerosol optical depth, Atmos. Meas. Tech., 14, 1405–1423 (2021).

Cusworth, D., R.M. Duren, A.K. Thorpe, S. Pandey, J.D. Maasakkers, I. Aben, D. Jervis, D. J. Varon, D. J. Jacob, C.A. Randles, R. Gautam, M. Omara, G. W. Schade, P. E. Dennison, C. Frankenberg, D. Gordon, E. Lopinto, C. E. Miller Multi-satellite imaging of a gas well blowout enables quantification of total methane emissions, Geophysical Research Letters, 48, e2020GL090864 (2021).

Shen, L., Zavala-Araiza, D., Gautam, R., Omara, M., Scarpelli, T., Sheng, J., … & Jacob, D. J. Unravelling a large methane emission discrepancy in Mexico using satellite observations. Remote Sensing of Environment, 260, 112461 (2021).

Zavala-Araiza, D., M. Omara, R. Gautam et al. A tale of two regions: Methane emissions from oil and gas production in offshore/onshore Mexico, Environmental Research Letters, 16 024019 (2021).

Lyon, D., B. Hmiel, R. Gautam et al., Concurrent variation in oil and gas methane emissions and oil price during the COVID-19 pandemic, Atmos. Chem. Phys., 21, 6605–6626, (2021)

Zhang, Y., Gautam, R., Pandey, S., Omara, M., Maasakkers, J. D., Sadavarte, P., Lyon, D., Nesser, H., Sulprizio, M. P., Varon, D. J., Zhang, R., Houweling, S., Zavala-Araiza, D., Alvarez, R. A., Lorente, A., Hamburg, S. P., Aben, I., & Jacob, D. J. (2020). Quantifying methane emissions from the largest oil-producing basin in the United States from space. Science Advances, 6(17), eaaz5120. * co-led the paper and was corresponding author. Impact factor – 14.95

Pandey, S., Gautam, R., Houweling, S., van der Gon, H. D., Sadavarte, P., Borsdorff, T., Hoogeveen, R., Hees, R. V., Hamburg, S. P., Maasakkers, J. D. & Aben, I. (2019). Satellite observations reveal extreme methane leakage from a natural gas well blowout. Proceedings of the National Academy of Sciences, 116(52), 26376-26381. Impact factor – 12.77 *co-led the paper.

Jethva, H., Torres, O., Field, R. D., Lyapustin, A., Gautam, R., & Kayetha, V. (2019). Connecting crop productivity, Residue fires, and Air Quality over northern India. Scientific Reports, 9(1), 1-11.

Patel, P. N., Gautam, R., Michibata, T., & Gadhavi, H. (2019). Strengthened Indian summer monsoon precipitation susceptibility linked to dust‐induced ice cloud modification. Geophysical Research Letters, 46(14), 8431-8441.

Várnai, T., Gatebe, C., Gautam, R., Poudyal, R., & Su, W. (2019). Developing an Aircraft-Based Angular Distribution Model of Solar Reflection from Wildfire Smoke to Aid Satellite-Based Radiative Flux Estimation. Remote Sensing, 11(13), 1509.

Liu, T., Marlier, M. E., Karambelas, A., Jain, M., Singh, S., Singh, M. K., Gautam, R., DeFries, R. S. (2019). Missing emissions from post-monsoon agricultural fires in northwestern India: regional limitations of MODIS burned area and active fire products. Environmental Research Communications, 1(1), 011007.

Zhang, Y., Gautam, R., Zavala‐Araiza, D., Jacob, D. J., Zhang, R., Zhu, L., … & Scarpelli, T. (2019). Satellite‐observed Changes in Mexico’s Offshore Gas Flaring Activity Linked to Oil/gas Regulations. Geophysical Research Letters, 46, 1879–1888.

Saikawa, E., Panday, A., Kang, S., Gautam, R., Zusman, E., Cong, Z., Somanathan, E., Adhikary, B. (2019). Air Pollution in the Hindu Kush Himalaya. In The Hindu Kush Himalaya Assessment (pp. 339-387). Springer, Cham. https://link.springer.com/chapter/10.1007/978-3-319-92288-1_10.

S. Kant, J. Panda, Gautam, R. (2019), A seasonal analysis of aerosol-cloud-radiation interaction over Indian region during 2000–2017, Atmospheric Environment, 201, 212-222.

Sheng, J. X., Jacob, D. J., Turner, A. J., Maasakkers, J. D., Benmergui, J., Bloom, A., Arndt, C., Gautam, R., Zavala-Araiza, D., Boesch, H., Parker, R.J. (2018). 2010–2016 methane trends over Canada, the United States, and Mexico observed by the GOSAT satellite: contributions from different source sectors. Atmospheric Chemistry and Physics, 18(16), 12257-12267.

Zhang, Y., Jacob, D. J., Maasakkers, J. D., Sulprizio, M. P., Sheng, J. X., Gautam, R., & Worden, J. (2018). Monitoring global tropospheric OH concentrations using satellite observations of atmospheric methane. Atmospheric Chemistry and Physics, 18(21), 15959-15973.

Gautam, R., and M. K. Singh, Urban Heat Island over Delhi punches Holes in Widespread Fog in the Indo-Gangetic Plains, Geophysical Research Letters, 45, 2018.

Kaskaoutis, D. G., E. E. Houssos, F. Solmon, M. Legrand, A. Rashki, U. C. Dumka, P. Francois, R. Gautam, R. P. Singh, Impact of atmospheric circulation types on southwest Asian dust and Indian summer monsoon rainfall, Atmospheric Research, 201, 189-205, 2018.

Salah, Z., A. Shalaby, A. L. Steiner, A. S. Zakey, R. Gautam, M. M. Abdel Wahab, Study of Aerosol Direct and Indirect effects and Auto-conversion processes over the West African Monsoon region using a regional climate model, Advances in Atmospheric Sciences, 35 (2), 182-194, 2018.

Singh, M. K., R. Gautam, P. Venkatachalam, Bayesian Merging of MISR and MODIS Aerosol Optical Depth Products using Error Distributions from AERONET, IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, doi: 10.1109/JSTARS.2017.2734331, 2017. * Selected as a Cover Article for IEEE JSTARS

Singh, M. K., P. Venkatachalam, R. Gautam, Geostatistical methods for filling gaps in Level-3 monthly mean Aerosol Optical Depth data from Multi-angle Imaging Spectroradiometer, Aerosol and Air Quality Research, doi:10.4209/aaqr.2016.02.0084, 2017.

Gautam, R., C. K. Gatebe, M. K. Singh, T. Varnai, R. Poudyal, Radiative Characteristics of Clouds Embedded in Smoke using multiangular airborne measurements, Journal of Geophysical Research- Atmospheres, doi:10.1002/2016JD025309, 2016.

Singh, M. K., R. Gautam, C. K. Gatebe, R. Poudyal, PolarBRDF: A general purpose Python package for visualization & quantitative analysis of multi-angular remote sensing measurements, Computers and Geosciences, 96, 173-180, 2016.

Pan, X., M. Chin, R. Gautam, H. Bian, D. Kim, P. R. Colarco, T. L. Diehl, T. Takemura, L. Pozzoli, K. Tsigaridis, S. Bauer, N. Bellouin, A multi-model evaluation of aerosols over South Asia: Common problems and possible causes, Atmospheric Chemistry Physics, 15, 5903-5928, doi:10.5194/acp-15-5903-2015, 2015.

Mukhopadhyay, B., A. Khan, R. Gautam, Rising and falling river flows: Contrasting signals of climate change from the eastern and western Karakoram, Hydrological Sciences Journal, 60(12), doi: 10.1080/02626667.2014.947291, 2015.

Gautam, R., “Challenges in Early Warning of the Persistent and Widespread Winter Fog over the Indo-Gangetic Plains: A Satellite Perspective” in “Early Warning Systems for Climate Change”, A. Singh, Z. Zommers (Eds.), pp 51-61, SPRINGER, 10.1007/978-94-017-8598-3_3, 2014.

Gautam, R., N. C. Hsu, T. F. Eck, B. N. Holben, S. Janjai, T. Jantarach, S. C. Tsay, K. M. Lau,Characterization of aerosols over the Indochina peninsula from satellite-surface observations during biomass burning pre-monsoon season, Atmospheric Environment, doi:10.1016/j.atmosenv.2012.05.038, 2013.

Tsay, S.-C, N.C. Hsu, W.K. Lau, C. Li, P.M. Gabriel, Q. Ji, B.N. Holben, E.J. Welton, A.X. Nguyen, S. Janjai, N-H. Lin, J.S. Reid, J. Boonjawat, S.G. Howell, B.J. Huebert, J.S. Fu, R.A. Hansell, A.M. Sayer, R. Gautam, S.-H. Wang, C.S.Goodloe, L.R. Miko, P.K. Shu, A.M. Loftus, J. Huang, J.Y. Kim, M.J. Jeong, P. Pantina, From BASE-ASIA towards 7-SEAS: A satellite-surface perspective of boreal spring biomass burning aerosols and clouds in southeast Asia, Atmospheric Environment, doi:10.1016/j.atmosenv.2012.12.013, 2013.

Gautam, R., N. C. Hsu, K. M. Lau, T. J. Yasunari, Satellite observations of desert dust-induced Himalayan Snow Darkening, Geophysical Research Letters, 40, doi:10.1002/grl.50226, 2013.

Verma, S., S. Payra, R. Gautam, D. Prakash, M. Soni, B. Holben, S. Bell, Dust events and their influence on aerosol optical properties over Jaipur in Northwestern India, Environmental Monitoring and Assessment, doi:10.1016/j.atmosenv.2012.05.038, 2013.

Hsu, N. C., R. Gautam, A. M. Sayer, C. Bettenhausen, C. Li, M. J. Jeong, S. C. Tsay, Global and regional trends of aerosols over land and ocean from SeaWiFS measurements from 1997 to 2010, Atmospheric Chemistry Physics, 12, 8037-8053, doi:10.5194/acpd-12-8037-2012, 2012.

Kaskaoutis, D. G., R. P. Singh, R. Gautam, M. Sharma, P.G. Kosmopoulos, B. Holben, Variability and Trends of Aerosol Properties over Kanpur, northern India using AERONET data (2001-2010), Environmental Research Letters, 7, doi:10.1088/1748-9326/7/2/024003, 2012.

Kaskaoutis, D., R. Gautam, R. P. Singh, E. Houssos, D. Goto, S. Singh, A. Bartzokas, P. G. Kosmopoulos, M. Sharma, N. C. Hsu, B. N. Holben, T. Takemura, Influence of drought monsoon conditions on aerosols over India: The role of meteorology and regional monsoon on aerosol emissions, distribution and properties, J. Geophysical Research, 117, D09106, doi:10.1029/2011JD017314, 2012.

Gautam, R., N. C. Hsu, S. C. Tsay, K. M. Lau, B. N. Holben, S. Bell, A. Smirnov, C. Li, R. Hansell, Q. Ji, S. Payra, D. Aryal, R. Kayastha, and K. M. Kim, Accumulation of aerosols over the Indo-Gangetic plains and southern slopes of the Himalayas: distribution, properties and radiative effects during the 2009 pre-monsoon season, Atmospheric Chemistry Physics, 11, 12841-12863, doi:10.5194/acp-11-12841-2011, 2011.

Gautam, R., N. C. Hsu, and K.-M. Lau (2010), Premonsoon aerosol characterization and radiative effects over the Indo-Gangetic Plains: Implications for regional climate warming, J. Geophysical Research, 115, D17208, doi:10.1029/2010JD013819.

Singh, R. P., W. Mehdi, R. Gautam, J. S. Kumar, J. Zlotnicki, M. Kafatos, Precursory signals using satellite and ground data associated with the Wenchuan Earthquake of 12 May 2008, International J. Remote Sensing, 3(13), doi:10.1080/01431161.2010.487503, 2010.

Gautam, R., N. C. Hsu, K.-M. Lau, and M. Kafatos (2009), Aerosol and Rainfall Variability over the Indian Monsoon Region: Distributions, Trends and Coupling, Ann. Geophys., 27, 3691-3703.

Gautam, R., Z. Liu, R. P. Singh, and N. C. Hsu (2009), Two contrasting dust-dominant periods over India observed from MODIS and CALIPSO data, Geophysical Research Letters, 36, L06813, doi:10.1029/2008GL036967.

Gautam, R., N. C. Hsu, K.‐M. Lau, S.‐C. Tsay, and M. Kafatos (2009), Enhanced pre‐monsoon warming over the Himalayan‐Gangetic region from 1979 to 2007, Geophysical Research Letters, 36, L07704, doi:10.1029/2009GL037641.

Gautam, R., N. C. Hsu, M. Kafatos, and S. C. Tsay (2007), Influences of winter haze on fog/low clouds over the Indo-Gangetic plains. J. Geophy. Res., 112, D05207, doi:10.1029/2005JD007036.

Kafatos, M., D. Sun, R. Gautam, Z. Boybeyi, R. Yang, G. Cervone (2006), Role of anomalous warm gulf

waters in the intensification of Hurricane Katrina, Geophysical Research Letters, 33, L17802, doi:10.1029/2006GL026623.

Sun, D., R. Gautam, G. Cervone, Z. Boybeyi, M. Kafatos (2006), Comment on “Satellite Altimetry and the Intensification of Hurricane Katrina”, Eos Trans. AGU, 87(8), 89.

El-Askary, H., R. Gautam, R. P. Singh, M. Kafatos (2006), Dust storms detection over the Indo-Gangetic basin using multi sensor data, Advances in Space Research, 37(4).

Gautam, R., G. Cervone, R. P. Singh, M. Kafatos (2005), Characteristics of meteorological parameters associated with Hurricane Isabel, Geophysical Research Letters, 32, L04801, doi:10.1029/2004GL021559.

Gautam, R., R. P. Singh, M. Kafatos (2005), Changes in ocean properties associated with Hurricane Isabel, International J. of Remote Sensing, 26(3), doi: 10.1080/01431160412331299226.

El-Askary, H., R. Gautam, M. Kafatos (2004), Remote Sensing of Dust Storms over Indo-Gangetic Basin, Journal of the Indian Society of Remote Sensing, 32(2).

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