Dr. Lok N. Lamsal is a GESTAR-affiliated Research Scientist at NASA Goddard Space Flight Center. His current research areas include development/improvement of retrieval algorithm for atmospheric trace gases from orbital and suborbital UV-visible sensors, validation of algorithm/products, and interpretation of satellite observations using in-situ data and model simulations. Prior to joining NASA, he was a postdoctoral fellow at Dalhousie University, Halifax, Canada. He received a Ph.D. in Atmospheric Science from the Institute of Remote Sensing, University of Bremen, Germany.
Lok N Lamsal
(SCIENTIST)
| Email: | lok.lamsal@nasa.gov |
| Phone: | 301.614.5160 |
| Org Code: | 614 |
| Address: |
NASA/GSFC Mail Code 614 Greenbelt, MD 20771 |
| Employer: | UNIVERSITY OF MARYLAND BALTIMORE CO |
Brief Bio
Positions/Employment
Senior Research Scientist
Goddard Earth Sciences Technology and Research (GESTAR) II, University of Maryland Baltimore County, Baltimore, MD 21250 - NASA Goddard Space Flight Center, Greenbelt, MD 20771
November 2021 - Present
Senior Scientist (Earth Science)
Goddard Earth Sciences Technology & Research, Universities Space Research Association - NASA Goddard Space Flight Center, Greenbelt, MD 20771
May 2018 - November 2021
Scientist II/Scientist III
Goddard Earth Sciences Technology & Research, Universities Space Research Association - NASA Goddard Flight Center, Greenbelt, MD 20771
2011 - 2018
Postdoctoral Fellow
Dalhousie University - Dalhousie University, Halifax, Nova Scotia, Canada B3H 4R2
2006 - 2011
Research Assistant
University of Bremen - University of Bremen, Otto-Hahn-Allee 1, D-28359, Bremen, Deutschland
2002 - 2006
Lecturer (Physics)
Tribhuvan University - Tribhuvan University, Kathmandu, Nepal
1999 - 2001
Awards
- NASA Robert H. Goddard Science Team Award (2021)
- NASA Goddard Earth Science Division Best Science Highlight or Nugget Award (2020)
- NASA Goddard Earth Science Division Distinguished Contribution Group Award
(2020)
- AMS Special Award – OMI Team (2020)
- William T. Pecora Award - OMI International Team (2018)
- NASA DISCOVER-AQ Group Achievement Award (2017)
- USRA President's Individual Excellence Award (2016)
- NASA Robert H. Goddard Exceptional Achievement Science Award (2015)
- NASA Goddard Laboratory for Atmospheres Outstanding Performance in Science
Award (2015)
- GESTAR Excellence Award (2014)
- Graduate scholarship – University of Bremen (2001-2002)
- M.Sc. Dissertation Grants, Nepal Academy of Science and Technology (1998)
Publications
Refereed
2024. "Revised estimates of NO2 reductions during the COVID-19 lockdowns using updated TROPOMI NO2 retrievals and model simulations." Atmospheric Environment 326 120459 [10.1016/j.atmosenv.2024.120459] [Journal Article/Letter]
2024. "Noise reduction for solar-induced fluorescence retrievals using machine learning and principal component analysis: simulations and applications to GOME-2 satellite retrievals." Artificial Intelligence for the Earth Systems [10.1175/aies-d-23-0085.1] [Journal Article/Letter]
2023. "Use of machine learning and principal component analysis to retrieve nitrogen dioxide (NO2) with hyperspectral imagers and reduce noise in spectral fitting." Atmospheric Measurement Techniques 16 (2): 481-500 [10.5194/amt-16-481-2023] [Journal Article/Letter]
2022. "Change in Tropospheric Ozone in the Recent Decades and Its Contribution to Global Total Ozone." Journal of Geophysical Research: Atmospheres 127 (22): [10.1029/2022jd037170] [Journal Article/Letter]
2022. "NASA Satellite Measurements Show Global‐Scale Reductions in Free Tropospheric Ozone in 2020 and Again in 2021 During COVID‐19." Geophysical Research Letters 49 (15): [10.1029/2022gl098712] [Journal Article/Letter]
2022. "Polarization Performance Simulation for the GeoXO Atmospheric Composition Instrument: NO2 Retrieval Impacts." Atmospheric Measurement Techniques 15 (15): 4489–4501 [doi.org/10.5194/amt-15-4489-2022] [Journal Article/Letter]
2022. "Global fine-scale changes in ambient NO2 during COVID-19 lockdowns." Nature 601 (7893): 380-387 [10.1038/s41586-021-04229-0] [Journal Article/Letter]
2022. "Use of Hyper-Spectral Visible and Near-Infrared Satellite Data for Timely Estimates of the Earth’s Surface Reflectance in Cloudy and Aerosol Loaded Conditions: Part 1–Application to RGB Image Restoration Over Land With GOME-2." Frontiers in Remote Sensing 2 [10.3389/frsen.2021.716430] [Journal Article/Letter]
2021. "CHAPS: a sustainable approach to targeted air pollution observation from small satellites." Sensors, Systems, and Next-Generation Satellites XXV [10.1117/12.2600175] [Proceedings]
2021. "Comprehensive evaluations of diurnal NO2 measurements during DISCOVER-AQ 2011: effects of resolution-dependent representation of NOx emissions." Atmospheric Chemistry and Physics 21 (14): 11133-11160 [10.5194/acp-21-11133-2021] [Journal Article/Letter]
2021. "Observations of Lightning NOx Production From GOES‐R Post Launch Test Field Campaign Flights." Journal of Geophysical Research: Atmospheres 126 (8): [10.1029/2020jd033769] [Journal Article/Letter]
2021. "Explicit and consistent aerosol correction for visible wavelength satellite cloud and nitrogen dioxide retrievals based on optical properties from a global aerosol analysis." Atmospheric Measurement Techniques 14 (4): 2857-2871 [10.5194/amt-14-2857-2021] [Journal Article/Letter]
2021. "Ozone Monitoring Instrument (OMI) Aura nitrogen dioxide standard product version 4.0 with improved surface and cloud treatments." Atmospheric Measurement Techniques 14 455-479 [10.5194/amt-14-455-2021] [Journal Article/Letter]
2020. "Surface and Satellite Observations of Air Pollution in India during COVID-19 Lockdown: Implication to Air Quality." Sustainable Cities and Society 102688 [10.1016/j.scs.2020.102688] [Journal Article/Letter]
2020. "Impact of COVID-19 on the Air Quality over China and India Using Long-term (2009-2020) Multi-satellite Data." Aerosol and Air Quality Research 21 (3): 200295 [10.4209/aaqr.2020.06.0295] [Journal Article/Letter]
2020. "Abrupt decline in tropospheric nitrogen dioxide over China after the outbreak of COVID-19." Science Advances 6 (28): eabc2992 [10.1126/sciadv.abc2992] [Journal Article/Letter]
2020. "Assessment of NO2; observations during DISCOVER-AQ and KORUS-AQ field campaigns." Atmospheric Measurement Techniques 13 (5): 2523-2546 [10.5194/amt-13-2523-2020] [Journal Article/Letter]
2020. "A methodology to constrain carbon dioxide emissions from coal-fired power plants using satellite observations of co-emitted nitrogen dioxide." Atmospheric Chemistry and Physics 20 99-116 [10.5194/acp-20-99-2020] [Journal Article/Letter]
2019. "Exploiting OMI NO2 satellite observations to infer fossil-fuel CO2 emissions from U.S. megacities." Science of The Total Environment 695 133805 [10.1016/j.scitotenv.2019.133805] [Journal Article/Letter]
2019. "Using satellite observations of tropospheric NO2 columns to infer long-term trends in US NOx emissions: the importance of accounting for the free tropospheric NO2 background." Atmospheric Chemistry and Physics 19 (13): 8863-8878 [10.5194/acp-19-8863-2019] [Journal Article/Letter]
2019. "High-Resolution Mapping of Nitrogen Dioxide With TROPOMI: First Results and Validation Over the Canadian Oil Sands." Geophysical Research Letters 46 (2): 1049-1060 [10.1029/2018gl081095] [Journal Article/Letter]
2018. "Atmospheric Trace Gas (NO2 and O3) Variability in South Korean Coastal Waters, and Implications for Remote Sensing of Coastal Ocean Color Dynamics." Remote Sensing 10 (10): 1587 [10.3390/rs10101587] [Journal Article/Letter]
2018. "Estimates of the Global Burden of Ambient PM2.5, Ozone, and NO2 on Asthma Incidence and Emergency Room Visits." Environmental Health Perspectives 126 (10): 107004 [10.1289/ehp3766] [Journal Article/Letter]
2018. "A cloud algorithm based on the O2-O2 477 nm absorption band featuring an advanced spectral fitting method and the use of surface geometry-dependent Lambertian-equivalent reflectivity." Atmospheric Measurement Techniques 11 (7): 4093-4107 [10.5194/amt-11-4093-2018] [Journal Article/Letter]
2017. "A decade of changes in nitrogen oxides over regions of oil and natural gas activity in the United States." Elem Sci Anth 5 (0): 76 [10.1525/elementa.259] [Journal Article/Letter]
2017. "The version 3 OMI NO2 standard product." Atmospheric Measurement Techniques 10 (9): 3133-3149 [10.5194/amt-10-3133-2017] [Journal Article/Letter]
2017. "Structural uncertainty in air mass factor calculation for NO2 and HCHO satellite retrievals." Atmospheric Measurement Techniques 10 (3): 759-782 [10.5194/amt-10-759-2017] [Journal Article/Letter]
2017. "High-resolution NO2 observations from the Airborne Compact Atmospheric Mapper: Retrieval and validation." Journal of Geophysical Research: Atmospheres 122 (3): 1953-1970 [10.1002/2016jd025483] [Journal Article/Letter]
2017. "What factors control the trend of increasing AAOD over the United States in the last decade?." Journal of Geophysical Research: Atmospheres 122 (3): 1797-1810 [10.1002/2016jd025472] [Journal Article/Letter]
2017. "Accounting for the effects of surface BRDF on satellite cloud and trace-gas retrievals: a new approach based on geometry-dependent Lambertian equivalent reflectivity applied to OMI algorithms." Atmospheric Measurement Techniques 10 (1): 333-349 [10.5194/amt-10-333-2017] [Journal Article/Letter]
2016. "Comparison of OMI NO2 observations and their seasonal andweekly cycles with ground-based measurements in Helsinki." Atmospheric Measurement Techniques 9 (10): 5203-5212 [10.5194/amt-9-5203-2016] [Journal Article/Letter]
2016. "Tropospheric emissions: Monitoring of pollution (TEMPO)." Journal of Quantitative Spectroscopy and Radiative Transfer 186 17-39 [10.1016/j.jqsrt.2016.05.008] [Journal Article/Letter]
2016. "Aura OMI observations of regional SO2 and NO2 pollution changes from 2005 to 2015." Atmos. Chem. Phys. 16 (7): 4605-4629 [10.5194/acp-16-4605-2016] [Journal Article/Letter]
2016. " A space-based, high-resolution view of notable changes in urban NO x pollution around the world (2005-2014) ." J. Geophys. Res. Atmos. 121 (2): 976–996 [10.1002/2015jd024121] [Journal Article/Letter]
2015. "Aura OMI observations of regional SO2 and NO2 pollution changes from 2005 to 2014." Atmos. Chem. Phys. 16 4605-4629 [10.5194/acp-16-4605-2016] [Journal Article/Letter]
2015. "Emissions of nitrogen oxides from US urban areas: estimation from Ozone Monitoring Instrument retrievals for 2005–2014 ." Atmos. Chem. Phys. 15 10367-10383 [10.5194/acp-15-10367-2015] [Journal Article/Letter]
2015. "Trends and variability in surface ozone over the United States." Journal of Geophysical Research: Atmospheres 120 [10.1002/2014JD022784] [Journal Article/Letter]
2015. "U.S. NO2 trends (2005–2013): EPA Air Quality System (AQS) data versus improved observations from the Ozone Monitoring Instrument (OMI)." Atmos. Env. 110 130-143 [10.1016/j.atmosenv.2015.03.055] [Journal Article/Letter]
2015. "Influence of satellite-derived photolysis rates and NOx emissions on Texas ozone modeling." Atmos. Chem. Phys. 15 (4): 1601-1619 [10.5194/acp-15-1601-2015] [Journal Article/Letter]
2014. "Evaluation of OMI operational standard NO2 column retrievals using in situ and surface-based NO2 observations." Atmos. Chem. Phys. 14 11,587-11,609 [10.5194/acp-14-11587-2014] [Journal Article/Letter]
2014. "Relationship between column-density and surface mixing ratio: Statistical analysis of O3 and NO2 data from the July 2011 Maryland DISCOVER-AQ mission." Atmospheric Environment 92 429-441 [10.1016/j.atmosenv.2014.04.041] [Journal Article/Letter]
2014. "Improved satellite retrievals of NO2 and SO2 over the Canadian oil sands and comparisons with surface measurements." Atmospheric Chemistry and Physics 14 (7): 3637-3656 [10.5194/acp-14-3637-2014] [Journal Article/Letter]
2014. "Using Satellite Observations to Measure." Environmental Manager 64 16-21 [Journal Article/Letter]
2013. "Emissions estimation from satellite retrievals: A review of current capability." Atmospheric Environment 77 1011-1042 [10.1016/j.atmosenv.2013.05.051] [Journal Article/Letter]
2013. "A new stratospheric and tropospheric NO2 retrieval algorithm for nadir-viewing satellite instruments: applications to OMI." Atmospheric Measurement Techniques 6 (10): 2607-2626 [10.5194/amt-6-2607-2013] [Journal Article/Letter]
2013. "Scaling Relationship for NO2 Pollution and Urban Population Size: A Satellite Perspective." Environmental Science & Technology 47 (14): 7855-7861 [10.1021/es400744g] [Journal Article/Letter]
2013. "The observed response of Ozone Monitoring Instrument (OMI) NO2 columns to NOx emission controls on power plants in the United States: 2005–2011." Atmospheric Environment 81 102-111 [10.1016/j.atmosenv.2013.08.068] [Journal Article/Letter]
2013. "Airborne MAX-DOAS measurements over California: Testing the NASA OMI tropospheric NO₂ product." J. Geophys. Res. Atmos. 118 (13): 7400–7413 [10.1002/jgrd.50550] [Journal Article/Letter]