Sciences and Exploration Directorate

Nickolay A Krotkov

(RSCH AST, ATMOSPHERIC CHEMISTRY & DYN)

Nickolay A Krotkov's Contact Card & Information.
Email: nickolay.a.krotkov@nasa.gov
Phone: 301.614.5553
Org Code: 614
Address:
NASA/GSFC
Mail Code 614
Greenbelt, MD 20771
Employer:
NASA

Missions & Projects

Brief Bio


EDUCATION

Ph.D., Oceanography, P.P.Shirshov Institute of Oceanology, Russian Academy of Sciences, 1990

Post-Graduate School, Moscow Institute of Physics and Technology (MIPT) 1987-1990

M.S., Remote Sensing, Moscow Institute of Physics and Technology (MIPT), 1985

B.S., Physics, Moscow Institute of Physics and Technology (MIPT), 1983

FIELDS OF SPECIALIZATION

Atmospheric chemistry, remote sensing of atmospheric trace gases and aerosols, theory and numerical methods in radiative transfer, retrieval algorithm development of atmospheric composition (aerosols and gases) from space (atmosphere, ocean and volcanic plumes monitoring) and ground air quality research.

EXPERIENCE SUMMARY

Dr. Nickolay A. Krotkov has over 30 years experience in radiative transfer, remote sensing observations, retrieval algorithm development, data analysis and research in the field of atmospheric composition (gases and aerosols). His Ph. D work in oceanography included radiative transfer modeling of the polarization effects of the solar radiation in the atmosphere-ocean system, as applied to passive spectral and polarization remote sensing of the atmospheric aerosols and water quality. Since 1993 he works with NASA Goddard Space Flight Center scientists to improve retrievals and understanding of Earth’s gas species such as sulfur dioxide, nitrogen dioxide, ozone and aerosols using remote sensing observations from satellite platforms and ground. His experience in radiative transfer and retrievals has led to algorithms for operational satellite data production. He developed first satellite algorithm for mapping surface UV irradiance from TOMS ozone and reflectivity data, which was adopted by the Finnish Meteorological Institute (FMI) for the Ozone Monitoring Instrument (OMI) production data (2004-current). In 2004 he developed a passive remote sensing method that led to discovery of enhanced column UV aerosol absorption due to organic aerosol. In part through his work absorbing aerosols (e.g., “brown” organic carbon) are now recognized as key to a complete understanding of surface UV radiation and atmospheric photochemistry. He developed a first operational OMI algorithm for retrieving sulfur dioxide from volcanoes and anthropogenic pollution and serves as principle investigator for the OMI volcanic and pollution sulfur dioxide products. Dr. Krotkov’s empirical and theoretical analysis of the sulfur dioxide data has led to quantification of passive emissions from active volcanoes and of anthropogenic pollution sources affecting air quality in North America, Europe, Russia, Chian, and India. Satellite volcanic SO2 data are now used in near real-time for detection of aviation hazards. In 2008 he developed an improved multiangle UV algorithm to derive vertical profile of ozone from ground based Brewer spectrometer data. Since 2010 he serves as PI for the OMI operational NO2 data. He demonstrated the great value that satellite sulfur dioxide and nitrogen dioxide data have in remotely identifying and quantifying point sources of emissions to the atmosphere. He is currently member of NASA Aura. EV-I TEMPO and DSCOVER/EPIC science teams, and disasters response team.


PRESENT POSITION

2010- Research Physical Scientist, Atmospheric Chemistry and Dynamics Laboratory, NASA Goddard Space Flight Center

Dr. Krotkov supervises production and improvements of operational SO2 and NO2 products from EOS Aura/OMI and Suomi NPP/OMPS instruments, performs data analysis of satellite measurements and geophysical research with satellite data, collaborates with NASA Headquarters, universities, other government agencies (USGS, NOAA) and international partners (Environment Canada, ESA, EUMETSAT, FMI, KNMI, BIRA); interprets and quality controls research results; presents findings at national and international meetings; prepares reports, contributes to international assessments and publishes manuscripts in professional journals. He is PI for volcanic SO2 and ash products from NASA’s EPIC UV camera on DSCOVR satellite at Lagrange 1 orbit. He is currently applying his knowledge in retrieval of atmospheric composition for planning of future satellite missions, such as NASA first geostationary air quality TEMPO mission. He retrieves aerosol absorption optical properties using combination of ground based passive radiometers and spectrometers.


Science Projects

2019 - PI, NASA ROSES19-PACESAT: "Hyperspectral algorithms for PACE OCI water leaving reflectances and UV penetration depths"

2016 – 2019 PI, NASA ROSES16: “Taking OMI NO2 to the next level: Inferring global fossil fuel CO2 emissions using OMI NO2 Data Improved with Critical Algorithm Updates”

2016 - 2019 Co-I, NASA ROSES16 : “Advancing NASA OMI SO2 product: Enabling new science analyses, applications, and long-term, multi-satellite monitoring”

2014 – 2019nNASA ROSES14 - Participating Investigator in ESA’s Sentinel 5 Precursor mission (TROPOMI)

2014 – 2018 PI, NASA ROSES 14 – DSCOVR science team (EPIC observations of Volcanic SO2 and ash)

2018 – PI, NASA DISASTERS: “Real-time Volcanic Cloud Products for Aviation Alerts”

2012 – Co-I, NASA EV-I TEMPO ST (NO2, SO2, surface UV algorithms)

2012 – 2017 PI, NASA ROSES2012-MEaSUREs: “Multi-Decadal Sulfur Dioxide Climatology from Satellite Instruments”


Web pages:

https://science.gsfc.nasa.gov/sed/bio/nickolay.a.krotkov

http://www.researcherid.com/rid/E-1541-2012

http://so2.gsfc.nasa.gov

Satellite Instrument team membership

2020 – NASA PACE SAT member

2015 – ESA S5P (TROPOMI) validation team member

2014 – NASA DSCOVR (EPIC) science team member

2012 – NASA EV-I TEMPO science team member

2011 – NASA GEO-TASO airborne UV/VIS spectrometer science team member

2011 - NASA GEO-CAPE formulation study science team member

2001- Aura/OMI science team member and PI responsible for SO2 and NO2 data.

1995-2006 TOMS ST member, responsible for surface UV algorithm development; volcanic ash and sulfur dioxide data sets.

Honors Received

NASA GSFC Peformance Awards: 2015, 2016, 2017, 2018,2019,2020

2020 – Council of the American Meteorological Society Special award to OMI team

2019 – NASA GSFC 610AT Peer Award for an outstanding Science Highlight

2018 – Dept of Interior/NASA William T. Pecora Group Award to OMI team for remote sensing

2013 – NASA Earth Venture-Instrument TEMPO science team award

2009 – NASA Robert H. Goddard Exceptional Achievement Science award

2008 – NASA group achievement award for OMI Instrument team

2006 – Dept of Interior/NASA William T. Pecora Group Award to TOMS team for remote sensing

2005 – NASA Group Achievement Award to the Aura Project

2005 – NASA Goddard Space Fligt Center Group Achievement Award to the Aura Team

1999– NASA Goddard Space Flight Center Laboratory for Atmospheres Outstanding Performance in Science Award 



Service to community

2015 – member, scientific committee of ESA’s Living Planet Symposium, Prague 2016

2014 – Co-Chair AIAA14 meeting on Volcanic Ash effects on Aviation; co-chair CEOS 2014 meeting;

2011 - Chair, Fall AGU session, Remote sensing of trace gases and aerosols: Air quality applications.

2005-2008 – UMBC/GEST: Leader: Atmospheric Chemistry focus area. Chair promotional committee.

2007 – Science organising committee member for International Conference “100 years of UV research”, PMOD, Davos, Switzerland;Contributor/author: Laboratory for Atmospheres annual reports; WMO Ozone assesments;

Reviewer: JGR, GRL, Atm. Environment, ACP, AMT

Universities collaborations

2012 – 2016 adjunct Professor, Physics Departmet, UMBC

2011 – 2016 Eric Hughes, AOSC Univesity of Maryland, College Park; advising Ph. D.

2010 – 2015 Adriana Lima, Physics Department, Univ of Maryland Baltimore County, Ph. D.

2014 - 2016 Jungbin Mok, ESSIC, Univesity of Maryland, College Park; advising Ph. D

2008 – 2010 Can Li, Ph. D. (committee member) Univesity of Maryland, College Park, Department of Atmospheric and Oceanic Sciences;

2007 - 2008 Brittany McClure, M. S. (committee member) Univesity of Maryland, College Park,

PRECEDING POSITIONS

Senior Research Scientist, Goddard Earth Scienes and Technology (GEST) Center ,

University of Maryland Baltimore County, Oct 2000 – November 2010

Conducted scientific investigations to improve the understanding of Earth’s troposphere gas species such as sulfur dioxide, ozone and aerosols using remote sensing observations from satellite platforms and ground. His satellite algorithm for mapping surface UV irradiance from TOMS ozone and reflectivity data was adopted by the Finnish Meteorological Institute (FMI) for the Ozone Monitoring Instrument (OMI) production data. He later developed a new algorithm for retrieving sulfur dioxide from volcanoes and anthropogenic pollution, which was adopted as the standard OMI data product. Since 2006 he served as principle investigator for the OMI volcanic and pollution sulfur dioxide products. Dr. Krotkov’s empirical and theoretical analysis of the sulfur dioxide data has led to quantification of passive emissions from active volcanoes and of anthropogenic pollution sources affecting air quality in North America, Europe, Russia, China, and South America. These data are now used in near real-time by NOAA for detection of aviation hazards from volcanic eruption clouds. For this work he was recipient of NASA group achivement awards (2005,2008), 2006 Pecora TOMS team award and the 2009 R.H. Goddard Exceptional Achievement in Science Award. In 2004 he developed a method that led to discovery of enhanced column UV aerosol absorption due to organic aerosol. In part through his work at GSFC absorbing aerosols (black and organic carbon, dust) are now recognized as key to a complete understanding of atmospheric chemistry, for they have large effects on ultraviolet radiation, and on photolysis rates of key pollution gases (ozone and nitrogen dioxide ). In 2008 he developed an improved multiangle ultra-violet algorithm to derive the vertical profile of ozone from ground based Brewer spectrometer data. Supervisor – Prof. Ray Hoff

Raytheon ITSS Corporation, Lanham, MD, Principal Scientist, July 1996-Oct 2000

Developed an algorithm for satellite UV volcanic ash retrievals using NASA Total Ozone Mapping Spectrometer (TOMS) instruments. For this work received Outstanding Performance in Science Award from the Laboratory for Atmospheres, NASA Goddard Space Flight Center. Developed applications of TOMS data, such as UV irradiance estimation at the Earth's surface and validated satellite UV retrievals using ground based UV measurements. Authored and co-authored 10 papers. Supervisor- Dr. Charles G. Wellemeyer

Department of Meteorology, University of Maryland, College Park, MD, Research Associate, Dec 1994 -July 1996 -Developed an improved retrieval algorithm of sulfur dioxide from the NASA TOMS satellite instrument. Performed data analysis of the effect of ozone depletion on ultraviolet (UV) irradiance at the Earth's surface and in the ocean. Performed validation of satellite UV maps with Russian spectral UV radiation data with data from NSF UV Spectroradiometer network in the United States. Authored and co-authored 2 papers. Supervisor- Prof. Robert Hudson.

Universities Space Research Association at NASA GSFC, Greenbelt, MD, Research Associate and Research Scientist, January 1993 - December 1994 - Analyzed sulfur dioxide data from NASA TOMS instruments. Developed a new computer model simulating propagation of solar UV radiation through the atmosphere-ocean system. Initiated the first intercomparisons of Russian spectral UV radiation data with data from NSF UV Spectroradiometer network in the United States. Supervisor- Dr.Michael W. Kalb

Central Aerological Observatory, Dolgoprudny, Russia, Research Associate, Sep 1990 – Dec 1992

Developed radiative transfer models for atmospheric scattering of solar UV radiation. Served as leader of the cooperative project in the framework of Russian State Science Program "Global Changes of Environment and Climate" aimed at the development of scientific approaches to monitoring surface UV radiation changes. Initiated and supervised development of a specialized archiving software package ("UVBase") facilitating analysis and intercomparisons of spectral UV radiation data. Supervisor- Dr. V. Khattatov, CAO Deputy Director

Moscow Institute of Physics and Technology (MIPT), Dolgoprudny, Russia, GRA, July 1986 – Sep 1990 -Junior Research Fellow (1986-1987) and Graduate Research Assistant (1987-1990) at the Department of Aerophysics and Space Research (Remote Sensing Laboratory). Primary research interests were in theoretical modeling of the polarization effects of the solar radiation in the atmosphere-ocean system, as applied to passive remote sensing of the minor atmospheric gases, aerosols and natural waters. In cooperation with an experimental team, participated in the optical and ecological expeditions in the regions of the Black and Baltic seas. Published 16 papers. Supervisor-Prof. T. V. Kondranin

PROFESSIONAL MEMBERSHIPS

American Geophysical Union

Research Interests


Satellite remote sensing of atmospheric composition from NASA EOS Aura and NASA/NOAA JPSS missions

Earth Science: Remote Sensing

Developed operational trace gas products (SO2, NO2) from the hyperspectral UV-Vis Ozone Monitoring Instrument (OMI) on NASA EOS Aura satellite (2004- current) and NASA/NOAA OMPS on Suomi NPP satellite (2017 - current)


Theory and numerical methods in Radiative Transfer

Earth Science: Solar Radiation

Radiative transfer numerical modeling of the angular and polarization effects of the solar radiation propagation in the atmosphere-ocean system, as applied to passive spectral and polarization remote sensing of the atmospheric aerosols and water quality. 


Satellite mapping of surface and underwater UV irradiance

Earth Science: Surface Properties

Developed first retrieval algorithms for global mapping of surface and underwater UV irradiance from NASA TOMS missions (1978-2005) and Aura Ozone Monitoring Instrument (2004-current) mission. Developing algorithms for NASA PACE Ocean Color Instrument retrievals of hyperspectral water leaving reflectances and UV penetration depths.


Satellite tracking of volcanic clouds

Earth Science: Remote Sensing

Developed a first operational Aura OMI algorithm for retrieving sulfur dioxide (SO2 ) from volcanoes and anthropogenic pollution. Analysis of the sulfur dioxide data has led to quantification of passive emissions from volcanoes and of anthropogenic pollution sources affecting air quality. Satellite volcanic SO2 data are now used in direct readout and near real-time for detection of aviation hazards. 

Current Projects


PI. Continuation of Multi-Decadal Global SO2 and NO2 Earth Science Data Records

Earth's Atmosphere

Sulfur Dioxide (SO2) and Nitrogen Dioxide (NO2) emitted from anthropogenic and natural sources have profound, long-term impacts on atmospheric composition, air quality (e.g., precursors of ozone and aerosols), ecosystems (e.g., acid rain and eutrophication) and the climate. They also provide timely updates on activity data, for example, during the COVID-19 lockdowns. Long-term, coherent multi-satellite SO2 and NO2 Earth Science Data Records (ESDRs) are critical for detecting changes in atmospheric composition and for projecting future changes in air quality and climate. Building such records requires sustained effort to develop ESDRs from different instruments, old and new, by processing them in a consistent fashion. 

           Our international team includes collaborators from Environment and Climate Change Canada, the Royal Netherlands Meteorological Institute (KNMI), Michigan Technological University (MTU), St. Louis Washington University, University of Maryland, and Smithsonian Global Volcanism Program, which have unique multi-decadal experience in producing and harmonizing SO2 and NO2 data from spaceborne instruments. Under the auspices of MEaSUREs-2012 (SO2) and MEaSUREs-2017 (NO2), we have released multiple ESDRs including our unique “top down” SO2 emission estimates from volcanic and anthropogenic sources. These ESDRs are produced with both current and legacy instruments that date back to the 1970s for SO2 and to the 1990s for NO2. They have been widely used by atmospheric, climate, and health scientists, air quality managers, economists, and geologists. The science value of these ESDRs grows significantly with their length, and it is critical to update and extend them as data continue to be acquired by current instruments:

https://so2.gsfc.nasa.gov/

https://so2.gsfc.nasa.gov/no2/no2_index.html

Teaching Experience


  • Advisor to UMD and UMBC graduate students and NASA postdoctoral scientists.
  • PhD committee member at AOSC/UMD, Physics Department/UMBC

Education


  • Ph.D., Oceanography, P.P.Shirshov Institute of Oceanology, Russian Academy of Sciences, 1990
  • Post-Graduate School, Moscow Institute of Physics and Technology (MIPT) 1987-1990
  • M.S., Remote Sensing, Moscow Institute of Physics and Technology (MIPT), 1985
  • B.S., Physics, Moscow Institute of Physics and Technology (MIPT), 1983

Professional Societies


American Geophysical Union

member

1995 - Present


American Meteorological Society

Member

2015 - Present

Professional Service


Session co-convener: American Geophysical Union Fall Meeting (2018, San Francisco, 2011- New Orleans)

Member, scientific committee of ESA’s Living Planet Symposium, Prague 2016

Co-chair AIAA14 meeting on Volcanic Ash effects on Aviation;

Co-chair CEOS 2014 meeting, Atlanta, GA

Science organizing committee member for International Conference “100 years of UV research”, 2007 PMOD, Davos, Switzerland;

Contributor/author: Laboratory for Atmospheres annual reports; WMO Ozone assesments;

Reviewer: JGR, GRL, Atm. Environment, ACP, AMT

Member: NASA proposal review panels.

Awards


2020 – Council of the American Meteorological Society Special award to OMI team

2019 – NASA GSFC 610AT Peer Award for an outstanding Science Highlight

2018 – Dept of Interior/NASA William T. Pecora group Award to OMI team

2013 – NASA Earth Venture-Instrument TEMPO science team award

2009 – NASA GSFC Robert H. Goddard Exceptional Achievement Science award

2008 – NASA group achievement award for OMI Instrument team

2006 – Dept of Interior/NASA William T. Pecora group Award to TOMS team

2005 – NASA Group Achievement Award to the Aura Project

2005 – NASA GSFC Group Achievement Award to the Aura Team

1999– NASA Goddard Space Flight Center (GSFC) Laboratory for Atmospheres Outstanding Performance in Science Award 


Grants


Day-Night Monitoring of Volcanic SO2 and Ash for Aviation Avoidance at Northern Polar Latitudes: Enhancing Direct Readout capabilities from EOS, SNPP and NOAA20

Day-Night Monitoring of Volcanic SO2 and Ash for Aviation Avoidance at Northern Polar Latitudes: Enhancing Direct Readout capabilities from EOS, SNPP and NOAA20 - NASA (NNH18ZDA001N-DISASTERS, Earth Science Applications: Disaster Risk Reduction and Response, A.37) - Awarded: 0000-00-00


Dates: 2019-07-08  - 2023-07-07

Coverage: 5.7

Amount $1,664,791 (5 years)

Publications


Refereed

2023. "Observing ocean ecosystem responses to volcanic ash." Remote Sensing of Environment 296 113749 [https://doi.org/10.1016/j.rse.2023.113749] [Journal Article/Letter]

2023. "Inverse Modeling of the Initial Stage of the 1991 Pinatubo Volcanic Cloud Accounting for Radiative Feedback of Volcanic Ash." Journal of Geophysical Research: Atmospheres 128 (12): [10.1029/2022jd038446] [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]

2023. "Version 2 of the global catalogue of large anthropogenic and volcanic SO2 sources and emissions derived from satellite measurements." Earth System Science Data 15 (1): 75-93 [10.5194/essd-15-75-2023] [Journal Article/Letter]

2022. "Perturbations in stratospheric aerosol evolution due to the water-rich plume of the 2022 Hunga-Tonga eruption." Communications Earth & Environment 3 (1): 248 [10.1038/s43247-022-00580-w] [Journal Article/Letter]

2022. "A new machine-learning-based analysis for improving satellite-retrieved atmospheric composition data: OMI SO2 as an example." Atmospheric Measurement Techniques 15 (18): 5497-5514 [10.5194/amt-15-5497-2022] [Journal Article/Letter]

2022. "Estimates of Hyperspectral Surface and Underwater UV Planar and Scalar Irradiances from OMI Measurements and Radiative Transfer Computations." Remote Sensing 14 (9): 2278 [10.3390/rs14092278] [Journal Article/Letter]

2022. "Using Machine Learning for Timely Estimates of Ocean Color Information From Hyperspectral Satellite Measurements in the Presence of Clouds, Aerosols, and Sunglint." Frontiers in Remote Sensing 3 [10.3389/frsen.2022.846174] [Journal Article/Letter]

2022. "Numerical Results for Polarized Light Scattering in a Spherical Atmosphere." Journal of Quantitative Spectroscopy and Radiative Transfer 287 108194 [10.1016/j.jqsrt.2022.108194] [Journal Article/Letter]

2022. "EarthShine: Observing our world as an exoplanet from the surface of the Moon." Journal of Astronomical Telescopes, Instruments, and Systems 8 (01): 014003 [10.1117/1.jatis.8.1.014003] [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. "Tracking aerosols and SO2 clouds from the Raikoke eruption: 3D view from satellite observations." Atmospheric Measurement Techniques 14 (12): 7545-7563 [10.5194/amt-14-7545-2021] [Journal Article/Letter]

2021. "A sulfur dioxide Covariance-Based Retrieval Algorithm (COBRA): application to TROPOMI reveals new emission sources." Atmospheric Chemistry and Physics 21 (22): 16727-16744 [10.5194/acp-21-16727-2021] [Journal Article/Letter]

2021. "Day–Night Monitoring of Volcanic SO2 and Ash Clouds for Aviation Avoidance at Northern Polar Latitudes." Remote Sensing 13 (19): 4003 [10.3390/rs13194003] [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. "Earth Imaging From the Surface of the Moon With a DSCOVR/EPIC-Type Camera." Frontiers in Remote Sensing 2 [10.3389/frsen.2021.724074] [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. "Version 2 Ozone Monitoring Instrument SO2 product (OMSO2 V2): new anthropogenic SO2 vertical column density dataset." Atmospheric Measurement Techniques 13 (11): 6175-6191 [10.5194/amt-13-6175-2020] [Journal Article/Letter]

2020. "Revised and extended benchmark results for Rayleigh scattering of sunlight in spherical atmospheres." Journal of Quantitative Spectroscopy and Radiative Transfer 254 107181 [10.1016/j.jqsrt.2020.107181] [Journal Article/Letter]

2020. "Ground-based retrievals of aerosol column absorption in the UV spectral region and their implications for GEMS measurements." Remote Sensing of Environment 245 111759 [10.1016/j.rse.2020.111759] [Journal Article/Letter]

2020. "Global distribution and 14-year changes in erythemal irradiance, UV atmospheric transmission, and total column ozone for2005–2018 estimated from OMI and EPIC observations." Atmospheric Chemistry and Physics 20 (14): 8351-8380 [10.5194/acp-20-8351-2020] [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. "High-resolution mapping of SO2 using airborne observations from the GeoTASO instrument during the KORUS-AQ field study: PCA-based vertical column retrievals." Remote Sensing of Environment 241 111725 [10.1016/j.rse.2020.111725] [Journal Article/Letter]

2020. "Stratospheric Injection of Massive Smoke Plume from Canadian Boreal Fires in 2017 as seen by DSCOVR‐EPIC, CALIOP and OMPS‐LP Observations." Journal of Geophysical Research: Atmospheres [10.1029/2020jd032579] [Journal Article/Letter]

2020. "Study of SO Pollution in the Middle East Using MERRA‐2, CAMS Data Assimilation Products, and High‐Resolution WRF‐Chem Simulations." Journal of Geophysical Research: Atmospheres 125 (6): [10.1029/2019jd031993] [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. "A geometry-dependent surface Lambertian-equivalent reflectivity product for UV-Vis retrievals - Part 2: Evaluation over open ocean." Atmospheric Measurement Techniques 12 (12): 6749-6769 [10.5194/amt-12-6749-2019] [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. "A geometry-dependent surface Lambertian-equivalent reflectivity product for UV–Vis retrievals – Part 1: Evaluation over land surfaces using measurements from OMI at 466nm." Atmospheric Measurement Techniques 12 (7): 3997-4017 [10.5194/amt-12-3997-2019] [Journal Article/Letter]

2019. "Surface erythemal UV irradiance in the continental United States derived from ground-based and OMI observations: quality assessment, trend analysis and sampling issues." Atmospheric Chemistry and Physics 19 (4): 2165-2181 [10.5194/acp-19-2165-2019] [Journal Article/Letter]

2019. "Linking improvements in sulfur dioxide emissions to decreasing sulfate wet deposition by combining satellite and surface observations with trajectory analysis." Atmospheric Environment 199 210-223 [10.1016/j.atmosenv.2018.11.039] [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. "A new global anthropogenic SO2 emission inventory for the last decade: a mosaic of satellite-derived and bottom-up emissions." Atmospheric Chemistry and Physics 18 (22): 16571-16586 [10.5194/acp-18-16571-2018] [Journal Article/Letter]

2018. "First Observations of Volcanic Eruption Clouds From the L1 Earth-Sun Lagrange Point by DSCOVR/EPIC." Geophysical Research Letters 45 (20): 11,456-11,464 [10.1029/2018gl079808] [Journal Article/Letter]

2018. "Earth Observations from DSCOVR/EPIC Instrument." Bulletin of the American Meteorological Society BAMS-D-17-0223.1 [10.1175/bams-d-17-0223.1] [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]

2018. "The Ozone Monitoring Instrument: overview of 14 years in space." Atmospheric Chemistry and Physics 18 (8): 5699-5745 [10.5194/acp-18-5699-2018] [Journal Article/Letter]

2018. "Comparisons of spectral aerosol single scattering albedo in Seoul, South Korea." Atmospheric Measurement Techniques 11 (4): 2295-2311 [10.5194/amt-11-2295-2018] [Journal Article/Letter]

2017. "Multi-source SO2 emission retrievals and consistency of satellite and surface measurements with reported emissions." Atmospheric Chemistry and Physics 17 (20): 12597-12616 [10.5194/acp-17-12597-2017] [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. "Retrieval of volcanic SO2 from HIRS/2 using optimal estimation." Atmospheric Measurement Techniques 10 (7): 2687-2702 [10.5194/amt-10-2687-2017] [Journal Article/Letter]

2017. "The net decay time of anomalies in concentrations of atmospheric pollutants." Atmospheric Environment 160 19-26 [10.1016/j.atmosenv.2017.04.006] [Journal Article/Letter]

2017. "Continuation of long-term global SO2 pollution monitoring from OMI to OMPS." Atmospheric Measurement Techniques 10 (4): 1495-1509 [10.5194/amt-10-1495-2017] [Journal Article/Letter]

2017. "A decade of global volcanic SO2 emissions measured from space." Scientific Reports 7 44095 [10.1038/srep44095] [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. "New-generation NASA Aura Ozone Monitoring Instrument (OMI) volcanic SO2 dataset: algorithm description, initial results, and continuation with the Suomi-NPP Ozone Mapping and Profiler Suite (OMPS)." Atmospheric Measurement Techniques 10 (2): 445-458 [10.5194/amt-10-445-2017] [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. "Impacts of brown carbon from biomass burning on surface UV and ozone photochemistry in the Amazon Basin." Nature Scientific Reports 6 36940 [10.1038/srep36940] [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. "Using CATS Near-Realtime Lidar Observations to Monitor and Constrain Volcanic Sulfur Dioxide (SO2) Forecasts." Geophysical Research Letters [10.1002/2016gl070119] [Journal Article/Letter]

2016. "A global catalogue of large SO2 sources and emissions derived from the Ozone Monitoring Instrument." Atmospheric Chemistry and Physics 16 (18): 11497-11519 [10.5194/acp-16-11497-2016] [Journal Article/Letter]

2016. "Limb–nadir matching using non-coincident NO2 observations: proof of concept and the OMI-minus-OSIRIS prototype product." Atmospheric Measurement Techniques 9 (8): 4103-4122 [10.5194/amt-9-4103-2016] [Journal Article/Letter]

2016. "Estimates of lightning NOx production based on OMI NO2 observations over the Gulf of Mexico." J. Geophys. Res. Atmos. 121 (14): 8668–8691 [10.1002/2015jd024179] [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. "Space-based detection of missing sulfur dioxide sources of global air pollution." Nature Geosci 9 496–500 [10.1038/ngeo2724] [Journal Article/Letter]

2016. "Ultraviolet Satellite Measurements of Volcanic Ash." Volcanic Ash 217-231 [10.1016/b978-0-08-100405-0.00018-5] [Article in Book]

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. "Satellite-based global volcanic SO2emissions and sulfate direct radiative forcing during 2005-2012." J. Geophys. Res. Atmos. 121 (7): 3446-3464 [10.1002/2015jd023134] [Journal Article/Letter]

2016. "Satellite observation of pollutant emissions from gas flaring activities near the Arctic." Atmospheric Environment 133 1-11 [10.1016/j.atmosenv.2016.03.019] [Journal Article/Letter]

2016. "Response of SO2and particulate air pollution to local and regional emission controls: A case study in Maryland." Earth's Future [10.1002/2015ef000330] [Journal Article/Letter]

2016. "A Decade of Change in NO2 and SO2 over the Canadian Oil Sands As Seen from Space." Environ. Sci. Technol. 50 (1): 331-337 [10.1021/acs.est.5b04985] [Journal Article/Letter]

2015. "Revising the slant column density retrieval of nitrogen dioxide observed by the Ozone Monitoring Instrument." J. Geophys. Res. Atmos. 120 (11): 5670-5692 [10.1002/2014jd022913] [Journal Article/Letter]

2015. "Comparison of operational satellite SO2 products with ground-based observations in northern Finland during the Icelandic Holuhraun fissure eruption." Atmospheric Measurement Techniques 8 (6): 2279-2289 [10.5194/amt-8-2279-2015] [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. "A new method for global retrievals of HCHO total columns from the Suomi National Polar-orbiting Partnership Ozone Mapping and Profiler Suite." Geophysical Research Letters 42 (7): 2515-2522 [10.1002/2015gl063204] [Journal Article/Letter]

2015. "Sulfur dioxide vertical column DOAS retrievals from the Ozone Monitoring Instrument: Global observations and comparison to ground-based and satellite data." J. Geophys. Res. Atmos. 120 (6): 2470-2491 [10.1002/2014jd022657] [Journal Article/Letter]

2015. " Lifetimes and emissions of SO2 from point sources estimated from OMI ." Geophysical Research Letters 42 (6): 1969-1976 [10.1002/2015gl063148] [Journal Article/Letter]

2015. " Extending the long-term record of volcanic SO2 emissions with the Ozone Mapping and Profiler Suite nadir mapper ." Geophysical Research Letters 42 (3): 925-932 [10.1002/2014gl062437] [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. "Global dry deposition of nitrogen dioxide and sulfur dioxide inferred from space-based measurements." Global Biogeochemical Cycles 28 (10): 1025-1043 [10.1002/2014gb004805] [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. "First estimates of global free-tropospheric NO2 abundances derived using a cloud-slicing technique applied to satellite observations from the Aura Ozone Monitoring Instrument (OMI)." Atmos. Chem. Phys. 14 (19): 10565-10588 [10.5194/acp-14-10565-2014] [Journal Article/Letter]

2014. "GEOS-5 sulfur dioxide simulations during the Frostburg, MD 2010 field campaign." Atmos. Chem. Phys. 14 1929-1941 [10.5194/acp-14-1929-2014] [Journal Article/Letter]

2014. "Optical, microphysical and compositional properties of the Eyjafjallajökull volcanic ash." Atmos. Chem. Phys. 14 10,649-10,661 [10.5194/acp-14-10649-2014] [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. "Characterization of OMI tropospheric NO2 over the Baltic Sea region." Atmos. Chem. Phys. 14 7795-7805 [10.5194/acp-14-7795-2014] [Journal Article/Letter]

2014. "Satellite data of atmospheric pollution for U.S. air quality applications: Examples of applications, summary of data end-user resources, answers to FAQs, and common mistakes to avoid." Atmospheric Environment 94 647-662 [10.1016/j.atmosenv.2014.05.061] [Journal Article/Letter]

2014. "Evaluation of GEOS-5 sulfur dioxide simulations during the Frostburg, MD 2010 field campaign." Atmos. Chem. Phys. 14 (4): 1929-1941 [10.5194/acp-14-1929-2014] [Journal Article/Letter]

2014. "Spatially and seasonally resolved estimate of the ratio of organic mass to organic carbon." Atmospheric Environment 87 34-40 [10.1016/j.atmosenv.2013.11.065] [Journal Article/Letter]

2013. "Ozone Monitoring Instrument Observations of Interannual Increases in SO 2 Emissions from Indian Coal-Fired Power Plants during 2005–2012." Environ. Sci. Technol. 47 (24): 13993-14000 [10.1021/es4039648] [Journal Article/Letter]

2013. "A fast and sensitive new satellite SO2 retrieval algorithm based on principal component analysis: Application to the ozone monitoring instrument." Geophysical Research Letters 40 (23): 6314-6318 [10.1002/2013gl058134] [Journal Article/Letter]

2013. "Application of OMI, SCIAMACHY, and GOME-2 satellite SO 2 retrievals for detection of large emission sources." J. Geophys. Res. Atmos. 118 (19): 11,399-11,418 [10.1002/jgrd.50826] [Journal Article/Letter]

2013. "Measuring global volcanic degassing with the Ozone Monitoring Instrument (OMI)." Geological Society, London, Special Publications 380 (1): 229-257 [10.1144/sp380.12] [Article in Book]

2013. "Airborne MAX-DOAS measurements over California: Testing the NASA OMI tropospheric NO 2 product." J. Geophys. Res. Atmos. 118 (13): 7400-7413 [10.1002/jgrd.50550] [Journal Article/Letter]

2013. "Modeling of 2008 Kasatochi volcanic sulfate direct radiative forcing: assimilation of OMI SO2 plume height data and comparison with MODIS and CALIOP observations." Atmos. Chem. Phys. 13 (4): 1895-1912 [10.5194/acp-13-1895-2013] [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. "Modeling of 2008 Kasatochi volcanic sulfate direct radiative forcing: assimilation of OMI SO₂ plume height data and comparison with MODIS and CALIOP observations." Atmos. Chem. Phys. 13 (4): 1895-1912 [10.5194/acp-13-1895-2013] [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]

2012. "Influence of desert dust intrusions on ground-based and satellite-derived ultraviolet irradiance in southeastern Spain." J. Geophys. Res. 117 (D19): [10.1029/2012jd018056] [Journal Article/Letter]

2012. "SO2 over central China: Measurements, numerical simulations and the tropospheric sulfur budget." J. Geophys. Res. 117 (D16): D00K37 [10.1029/2011JD016473] [Journal Article/Letter]

2012. "Fog- and cloud-induced aerosol modification observed by the Aerosol Robotic Network (AERONET)." J Geophys Res 117 (D7): D07206 [10.1029/2011JD016839] [Journal Article/Letter]

2012. "Likely seeding of cirrus clouds by stratospheric Kasatochi volcanic aerosol particles near a mid-latitude tropopause fold." Atmospheric Environment 46 441-448 [10.1016/j.atmosenv.2011.09.027] [Journal Article/Letter]

2012. "Air quality over the Canadian oil sands: A first assessment using satellite observations." Geophysical Research Letters 39 (4): L04804 [10.1029/2011GL050273] [Journal Article/Letter]

2012. "Flux calculation using CARIBIC DOAS aircraft measurements: SO2 emission of Norilsk." J. Geophys. Res. 117 (D11): D11305 [10.1029/2011JD017335] [Journal Article/Letter]

2012. "Rapid transpacific transport in autumn observed by the A-train satellites." J. Geophys. Res. 117 (D6): D06312 [10.1029/2011JD016626] [Journal Article/Letter]

2011. "Estimation of SO 2 emissions using OMI retrievals." Geophysical Research Letters 38 (21): [10.1029/2011gl049402] [Journal Article/Letter]

2011. "In situ measurements of tropospheric volcanic plumes in Ecuador and Colombia during TC 4." Journal of Geophysical Research 116 D00J24 [10.1029/2010jd014718] [Journal Article/Letter]

2011. "Global satellite analysis of the relation between aerosols and short-lived trace gases." Atmos. Chem. Phys. 11 (3): 1255-1267 [10.5194/acp-11-1255-2011] [Journal Article/Letter]

2011. "SO2 emissions and lifetimes: Estimates from inverse modeling using in situ and global, space-based (SCIAMACHY and OMI) observations." J Geophys Res 116 (D6): D06304 [10.1029/2010JD014758] [Journal Article/Letter]

2010. "Direct retrieval of sulfur dioxide amount and altitude from spaceborne hyperspectral UV measurements: Theory and application." Journal of Geophysical Research 115 D00L09 [10.1029/2010jd013982] [Journal Article/Letter]

2010. "Validation of ozone monitoring instrument SO 2 measurements in the Okmok volcanic cloud over Pullman, WA, July 2008." Journal of Geophysical Research 115 D00L08 [10.1029/2009jd013492] [Journal Article/Letter]

2010. "Comparison of TOMS retrievals and UVMRP measurements of surface spectral UV radiation in the United States." Atmos. Chem. Phys. 10 (18): 8669-8683 [10.5194/acp-10-8669-2010] [Journal Article/Letter]

2010. "Comparison of UV irradiances from Aura/Ozone Monitoring Instrument (OMI) with Brewer measurements at El Arenosillo (Spain) – Part 1: Analysis of parameter influence." Atmos. Chem. Phys. 10 (13): 5979-5989 [10.5194/acp-10-5979-2010] [Journal Article/Letter]

2010. "A Balloon Sounding Technique for Measuring SO2 Plumes." Journal of Atmospheric and Oceanic Technology 27 (8): 1318-1330 [10.1175/2010JTECHA1436.1] [Journal Article/Letter]

2010. "Comparison of UV irradiances from Aura/Ozone Monitoring Instrument (OMI) with Brewer measurements at El Arenosillo (Spain) – Part 2: Analysis of site aerosol influence." Atmos. Chem. Phys. 10 (23): 11867-11880 [10.5194/acp-10-11867-2010] [Journal Article/Letter]

2010. "Dispersion and lifetime of the SO 2 cloud from the August 2008 Kasatochi eruption." J Geophys Res 115 (D2): D00L20 [10.1029/2010JD013984] [Journal Article/Letter]

2010. "Recent large reduction in sulfur dioxide emissions from Chinese power plants observed by the Ozone Monitoring Instrument." Geophysical Research Letters 37 (8): L08807 [10.1029/2010GL042594] [Journal Article/Letter]

2010. "Transport and evolution of a pollution plume from northern China: A satellite-based case study." J Geophys Res 115 (D7): D00K03 [10.1029/2009JD012245] [Journal Article/Letter]

2009. "Hit from both sides: tracking industrial and volcanic plumes in Mexico City with surface measurements and OMI SO2 retrievals during the MILAGRO field campaign." Atmos. Chem. Phys. 9 (24): 9599-9617 [10.5194/acp-9-9599-2009] [Journal Article/Letter]

2009. "What would have happened to the ozone layer if chlorofluorocarbons (CFCs) had not been regulated?." Atmos. Chem. Phys. 9 (6): 2113-2128 [10.5194/acp-9-2113-2009] [Journal Article/Letter]

2009. "Retrieval of aerosol single scattering albedo at ultraviolet wavelengths at the T1 site during MILAGRO." Atmos. Chem. Phys. 9 (15): 5813-5827 [10.5194/acp-9-5813-2009] [Journal Article/Letter]

2009. "Hit from both sides: tracking industrial and volcanic plumes in Mexico City with surface measurements and OMI SO₂ retrievals during the MILAGRO field campaign." Atmos. Chem. Phys. 9 (24): 9599-9617 [10.5194/acp-9-9599-2009] [Journal Article/Letter]

2009. "Ozone Monitoring Instrument spectral UV irradiance products: comparison with ground based measurements at an urban environment." Atmos. Chem. Phys. 9 (2): 585-594 [10.5194/acp-9-585-2009] [Journal Article/Letter]

2009. "Applications of Satellite-Based Sulfur Dioxide Monitoring." IEEE J. Sel. Top. Appl. Earth Observations Remote Sensing 2 (4): 293-298 [10.1109/JSTARS.2009.2037334] [Journal Article/Letter]

2009. "Retrieval of vertical columns of sulfur dioxide from SCIAMACHY and OMI: Air mass factor algorithm development, validation, and error analysis." J. Geophys. Res. 114 (D22303): [10.1029/2009JD012123] [Journal Article/Letter]

2009. "Tracking volcanic sulfur dioxide clouds for aviation hazard mitigation." Nat Hazards 51 (2): 325-343 [10.1007/s11069-008-9228-4] [Journal Article/Letter]

2009. "A new approach to correct for absorbing aerosols in OMI UV." Geophys Res Lett 36 (22): L22805 [10.1029/2009GL041137] [Journal Article/Letter]

2009. "Satellite observations of changes in air quality during the 2008 Beijing Olympics and Paralympics." Geophys Res Lett 36 (17): L17803 [10.1029/2009GL039236] [Journal Article/Letter]

2009. "Estimating the altitude of volcanic sulfur dioxide plumes from space borne hyper-spectral UV measurements." Geophys Res Lett 36 (L10803): [10.1029/2009GL038025] [Journal Article/Letter]

2009. "Improving retrieval of volcanic sulfur dioxide from backscattered UV satellite observations." Geophysical Research Letters 36 (3): L03102 [10.1029/2008GL036036] [Journal Article/Letter]

2008. "Daily monitoring of Ecuadorian volcanic degassing from space." Journal of Volcanology and Geothermal Research 176 (1): 141-150 [10.1016/j.jvolgeores.2008.01.029] [Journal Article/Letter]

2008. "Description and validation of the OMI very fast delivery products." J Geophys Res 113 (D16S35): [10.1029/2007JD008784] [Journal Article/Letter]

2008. "El Chichon: The genesis of volcanic sulfur dioxide monitoring from space." J Volcanol Geotherm Res 175 (4): 408-414 [10.1016/j.jvolgeores.2008.02.026] [Journal Article/Letter]

2008. "A new technique for retrieval of tropospheric and stratospheric ozone profiles using sky radiance measurements at multiple view angles: Application to a Brewer spectrometer." Journal of Geophysical Research – Atmospheres 113 (D6): D06304 [10.1029/2007JD009093] [Journal Article/Letter]

2008. "Validation of SO2 retrievals from the Ozone Monitoring Instrument over NE China." J Geophys Res 113 (D16S40, doi:101029/): [Journal Article/Letter]

2007. "Aircraft observations of dust and pollutants over northeast China: Insight into the meteorological mechanisms of transport." Journal of Geophysical Research 112 (D24): D24S90 [10.1029/2007jd008999] [Journal Article/Letter]

2007. "Validation of daily erythemal doses from Ozone Monitoring Instrument with ground-based UV measurement data." Journal of Geophysical Research 112 (D24): D24S44 [10.1029/2007jd008830] [Journal Article/Letter]

2007. "Retrieval of large volcanic SO 2 columns from the Aura Ozone Monitoring Instrument: Comparison and limitations." Journal of Geophysical Research 112 (D24): D24S43 [10.1029/2007jd008825] [Journal Article/Letter]

2007. "Total ozone mapping spectrometer retrievals of noon erythemal-CIE ultraviolet irradiance compared with Brewer ground-based measurements at El Arenosillo (southwestern Spain)." Journal of Geophysical Research 112 (D11): D11206 [10.1029/2006jd007254] [Journal Article/Letter]

2007. "Extended observations of volcanic SO2 and sulfate aerosol in the stratosphere." Atmos Chem Phys Discuss 7 2857-2871 [Journal Article/Letter]

2007. "Sulfur dioxide emissions from Peruvian copper smelters detected by the Ozone Monitoring Instrument." Geophy Res Lett 34 L09801 [Journal Article/Letter]

2007. "Total ozone mapping spectrometer retrievals of noon erythermal-CIE ultraviolet irradiance compared with Brewer ground-based measurements at E1 Arenosillo (southwestern Spain)." J Geopohys Res 112 D11206 [Journal Article/Letter]

2006. "Comparison of satellite-derived UV irradiances with ground-based measurements at four European stations." J Geophys Res 111 D13207 [10.1029/2005JD006672] [Journal Article/Letter]

2006. "Surface ultraviolet irradiance from OMI." IEEE Transactions on Geoscience and Remote Sensing 44 (5): 1267-1271 [10.1109/tgrs.2005.862203] [Journal Article/Letter]

2006. "Band Residual Difference Algorithm for Retrieval of SO2 from the Aura Ozone Monitoring Instrument (OMI)." IEEE Transactions on Geoscience and Remote Sensing 44 (5): 1259-1266 [10.1109/TGRS.2005.861932] [Journal Article/Letter]

2006. "Measurements of nitrogen dioxide total column amounts using a Brewer double spectrophotometer in direct Sun mode." Journal of Geophysical Research 111 (D5): D05304 [10.1029/2005jd006585] [Journal Article/Letter]

2006. "Measurements of Nitrogen Dioxide Total Column Amounts Using a Brewer Spectrometer in Direct Sun Mode." J Geophys Res 111 D05304 [Journal Article/Letter]

2006. "Photomineralization of terrigenous dissolved organic matter in Arctic coastal waters from 1979 to 2003: Interannual variability and implications of climate change." Global Biogeochem Cycles 20 GB4005 [Journal Article/Letter]

2006. "Surface Ultraviolet Irradiance from OMI." IEEE Trans on Geosc And Remote Sensing 44 (5): IGRSD2 1267-1271 [Journal Article/Letter]

2005. "Aerosol ultraviolet absorption experiment (2002 to 2004), part 1: ultraviolet multifilter rotating shadowband radiometer calibration and intercomparison with CIMEL sunphotometers." Opt Eng 44 (4): 041004-1 - 041004-17 [10.1117/1.1886818] [Journal Article/Letter]

2005. "Assessment of TOMS UV bias due to absorbing aerosols." Journal of Geophysical Research 110 (D23): D23211 [10.1029/2005jd005913] [Journal Article/Letter]

2005. "Assessment of TOMS UV bias due to absorbing aerosols." J. Geophys. Res. 110 (D23): D23211 [10.1029/2005JD005913] [Journal Article/Letter]

2005. "Aerosol ultraviolet absorption experiment (2002 to 2004), part 2: absorption optical thickness, refractive index, and single scattering albedo." Opt Eng 44 (4): 041005-1 - 041005-17 [10.1117/1.1886819] [Journal Article/Letter]

2004. "UV index climatology over the United States and Canada from ground-based and satellite estimates." J. Geophys. Res. 109 (D22): [10.1029/2004jd004820] [Journal Article/Letter]

2004. "Fire at Iraqi sulfur plant emits SO2 clouds detected by Earth Probe TOMS." Geophys. Res. Lett. 31 (L19105): 10.1029/2004GL020719 [Journal Article/Letter]

2004. "Spectral properties of backscattered UV radiation in cloudy atmospheres." J. Geophys. Res. 109 (D1): D01201 [10.1029/2003JD003395] [Journal Article/Letter]

2003. "Volcanic eruption detection by the Total Ozone Mapping Spectrometer (TOMS) instruments: a 22-year record of sulphur dioxide and ash emissions." Geological Society, London, Special Publications 213 (1): 177-202 [10.1144/gsl.sp.2003.213.01.11] [Journal Article/Letter]

2003. "International Photolysis Frequency Measurement and Model Intercomparison (IPMMI): Spectral actinic solar flux measurements and modeling." J. Geophys. Res. 108 (D16): 8543 [doi:10.1029/2002JD002891] [Journal Article/Letter]

2003. " A new approach to estimating the albedo for snow-covered surfaces in the satellite UV method." J. Geophys. Res. 108 (D17): 4531 [doi:10.1029/2003JD003492] [Journal Article/Letter]

2002. "Retrieval of ozone column from global irradiance measurements and comparison with TOMS data. A year of data in the Alps." Geophysical Research Letters 29 (9): 23-1-23-4 [10.1029/2002gl014823] [Journal Article/Letter]

2002. "Version 2 TOMS UV algorithm: problems and enhancements." Opt. Eng. 41 (12): 3028-3039 [doi: 10.1117/1.1519541] [Journal Article/Letter]

2002. "Version 2 total ozone mapping spectrometer ultraviolet algorithm: problems and enhancements." Optical Engineering 41 (12): 3028-3039 [10.1117/1.1519541] [Journal Article/Letter]

2002. "Problems in assessment of the UV penetration into natural waters from space-based measurements." Optical Engineering 41 3019-3027 [Journal Article/Letter]

2001. "Global mapping of underwater UV irradiances and DNA-weighted exposures using Total Ozone Mapping Spectrometer and Sea-viewing Wide Field-of-view Sensor data products." Journal of Geophysical Research: Oceans 106 (C11): 27205-27219 [10.1029/2000jc000373] [Journal Article/Letter]

2000. "Reduction of skylight reflection effects in the above-water measurement of diffuse marine reflectance: comment." Applied Optics 39 (9): 1379 [10.1364/ao.39.001379] [Journal Article/Letter]

1999. "Comparison of TOMS and AVHRR Volcanic Ash Retrievals from the August 1992 Eruption of Mt Spurr." Geophys Res Lett 26 (4): 455-458 [10.1029/1998GL900278] [Journal Article/Letter]

1999. "A model for calculation of ultraviolet radiation transfer in Arctic waters." Oceanology 39 (2): 172-180 [Journal Article/Letter]

1997. "Detection of volcanic ash clouds from Nimbus-7/Total Ozone Mapping Spectrometer." J. Geophys. Res. 102 (D14): 16749-16760 [10.1029/97JD00925] [Journal Article/Letter]

1993. "The accuracy of biooptical parameters retrieval from the spectral sea reflectance." IRS '92: Current Problems in Atmospheric Radiation 421-424 [Article in Book]

1990. "Properties of the angular dependence of polarization for upward radiation from the sea surface in the visible region of the spectrum." Izvestiya, Atmospheric and Oceanic Physics 26 (5): 397-401 [Journal Article/Letter]

1990. "The effectiveness of polarisation measurements in passive remote sensing of the ocean in the visible region of the spectrum." Sov. J. Remote Sensing 7 (5): 886-899 [Journal Article/Letter]

Non-Refereed

1993. "Ultraviolet radiation in the atmosphere-ocean system: a model study." Atmospheric Radiation 2049 244-255 [10.1117/12.163517] [Proceedings]

1992. "Optimization of the polarization remote-sensing techniques of the ocean." Polarization and Remote Sensing SPIE 1747 188-199 [10.1117/12.138836] [Proceedings]

Talks, Presentations and Posters


Invited

Real-time Volcanic Cloud Products and Predictions for Aviation Alerts

March 24, 2017

Invited talk to Technology in Science and Operations Seminar on Volcanic Cloud Products and Applications for Aviation aspects at NOAA-NVWCP- SAB-WVAAC in College park, MD

Other

Selected Public Outreach


NASA Satellite Finds Unreported Sources of Toxic Air Pollution

July 2016 - Present

Using a new satellite-based method, scientists at NASA, Environment and Climate Change Canada, and two universities have located 39 unreported and major human-made sources of toxic sulfur dioxide emissions.


NASA Scientists Scrutinize Arctic Gas Flaring Pollution

May 2016 - Present

Flaring of waste natural gas from industrial oil fields in the Northern Hemisphere is a potential source of significant amounts of nitrogen dioxide and black carbon to the Arctic, according to a new NASA study.