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Timothy B. Onasch

Timothy B. Onasch

D-Index & Metrics

Environmental Sciences

D-Index
92
Citations
35498
World Ranking
537
National Ranking
243

Overview

Timothy B. Onasch is a researcher affiliated with Boston College in the United States. Their work primarily focuses on environmental science and earth and planetary sciences, with particular contributions in atmospheric science and global and planetary change. They have published extensively on topics related to atmospheric chemistry and aerosols, atmospheric aerosols and clouds, air quality and health impacts, vehicle emissions and performance, and atmospheric ozone and climate.

Their recent publications include research on aerosol particles, wildfire smoke, and biomass-burning emissions. Notable papers are:

  • Radiative absorption enhancements by black carbon controlled by particle-to-particle heterogeneity in composition (2020, Proceedings of the National Academy of Sciences)
  • Oxygenated Aromatic Compounds are Important Precursors of Secondary Organic Aerosol in Biomass-Burning Emissions (2020, Environmental Science & Technology)
  • Rapid evolution of aerosol particles and their optical properties downwind of wildfires in the western US (2020, Atmospheric Chemistry and Physics)
  • Biomass-burning-derived particles from a wide variety of fuels - Part 2: Effects of photochemical aging on particle optical and chemical properties (2020, Atmospheric Chemistry and Physics)
  • Shortwave absorption by wildfire smoke dominated by dark brown carbon (2023, Nature Geoscience)

The researcher frequently publishes in several scientific venues including:

  • Atmospheric Chemistry and Physics
  • Aerosol Science and Technology
  • Atmospheric Measurement Techniques
  • Environmental Science & Technology
  • Journal of Aerosol Science

Onasch collaborates with several co-authors with whom they have multiple publications. Frequent collaborators include Andrew Freedman, Arthur J. Sedlacek, Yue Zhang, John S. Kinsey, and Jeffrey Stevens.

The main topics they address center around the properties and impacts of atmospheric aerosols, examining how these particles influence atmospheric chemistry, cloud formation, and air quality. Their work also intersects with vehicle emissions and performance, as well as studying fire effects on ecosystems.

Best Publications

  • Evolution of Organic Aerosols in the Atmosphere

    J. L. Jimenez;M. R. Canagaratna;N. M. Donahue;A. S. H. Prevot

  • Ubiquity and dominance of oxygenated species in organic aerosols in anthropogenically-influenced Northern Hemisphere midlatitudes

    Q. Zhang;Jose L. Jimenez;M. R. Canagaratna;J. D. Allan

  • Chemical and microphysical characterization of ambient aerosols with the aerodyne aerosol mass spectrometer

    M. R. Canagaratna;J. T. Jayne;J. L. Jimenez;J. D. Allan

  • O/C and OM/OC Ratios of Primary, Secondary, and Ambient Organic Aerosols with High-Resolution Time-of-Flight Aerosol Mass Spectrometry

    Allison C. Aiken;Peter F. DeCarlo;Jesse H. Kroll;Douglas R. Worsnop

  • An Aerosol Chemical Speciation Monitor (ACSM) for Routine Monitoring of the Composition and Mass Concentrations of Ambient Aerosol

    N. L. Ng;S. C. Herndon;A. Trimborn;M. R. Canagaratna

  • Radiative Absorption Enhancements Due to the Mixing State of Atmospheric Black Carbon

    Christopher D. Cappa;Timothy B. Onasch;Paola Massoli;Douglas R. Worsnop

  • A generalised method for the extraction of chemically resolved mass spectra from aerodyne aerosol mass spectrometer data

    James D Allan;Alice E Delia;Hugh Coe;Keith N Bower

  • Soot Particle Aerosol Mass Spectrometer: Development, Validation, and Initial Application

    T. B. Onasch;A. Trimborn;E. C. Fortner;J. T. Jayne

  • Transmission Efficiency of an Aerodynamic Focusing Lens System: Comparison of Model Calculations and Laboratory Measurements for the Aerodyne Aerosol Mass Spectrometer

    Peter S. K. Liu;Rensheng Deng;Kenneth A. Smith;Leah R. Williams

  • Laboratory studies of the chemical composition and cloud condensation nuclei (CCN) activity of secondary organic aerosol (SOA) and oxidized primary organic aerosol (OPOA)

    A.T. Lambe;T.B. Onasch;P. Massoli;D.R. Croasdale

  • Characterization of aerosol photooxidation flow reactors: heterogeneous oxidation, secondary organic aerosol formation and cloud condensation nuclei activity measurements

    A.T. Lambe;A.T. Ahern;L.R. Williams;J.G. Slowik

  • Characterization of ambient aerosols in Mexico City during the MCMA-2003 campaign with Aerosol Mass Spectrometry: results from the CENICA Supersite

    D. Salcedo;D. Salcedo;T. B. Onasch;K. Dzepina;M. R. Canagaratna

  • Enhanced light absorption by mixed source black and brown carbon particles in UK winter

    Shang Liu;Shang Liu;Allison C. Aiken;Kyle Gorkowski;Kyle Gorkowski;Manvendra K. Dubey

  • Collection Efficiencies in an Aerodyne Aerosol Mass Spectrometer as a Function of Particle Phase for Laboratory Generated Aerosols

    Brendan M. Matthew;Ann M. Middlebrook;Timothy B. Onasch

  • Relationship between oxidation level and optical properties of secondary organic aerosol.

    Andrew T. Lambe;Christopher D. Cappa;Paola Massoli;Timothy B. Onasch

  • An Inter-Comparison of Instruments Measuring Black Carbon Content of Soot Particles

    Jay G. Slowik;Eben S. Cross;Jeong-Ho Han;Paul Davidovits

  • A Novel Method for Estimating Light-Scattering Properties of Soot Aerosols Using a Modified Single-Particle Soot Photometer

    R. S. Gao;J. P. Schwarz;K. K. Kelly;D. W. Fahey

  • Use of electrochemical sensors for measurement of air pollution: correcting interference response and validating measurements

    Eben S. Cross;Leah R. Williams;David K. Lewis;Gregory R. Magoon

  • Relationship between aerosol oxidation level and hygroscopic properties of laboratory generated secondary organic aerosol (SOA) particles

    P. Massoli;A.T. Lambe;A.T. Ahern;L.R. Williams

  • Airborne measurements of western U.S. wildfire emissions: Comparison with prescribed burning and air quality implications

    Xiaoxi Liu;Xiaoxi Liu;Xiaoxi Liu;L. Gregory Huey;Robert J. Yokelson;Vanessa Selimovic

  • Soot Particle Studies—Instrument Inter-Comparison—Project Overview

    Eben S. Cross;Timothy B. Onasch;Adam Ahern;William Wrobel

  • Technical note A generalised method for the extraction of chemically resolved mass spectra from Aerodyne aerosol mass spectrometer data

    James D. Allan;Alice E. Delia;Hugh Coe;Keith N. Bower

Frequent Co-Authors

Douglas R. Worsnop
Douglas R. Worsnop University of Helsinki
Paul Davidovits
Paul Davidovits Boston College
Paola Massoli
Paola Massoli Earth System Research Laboratory
Scott C. Herndon
Scott C. Herndon Aerodyne Research
Jose L. Jimenez
Jose L. Jimenez University of Colorado Boulder
Leah R. Williams
Leah R. Williams Aerodyne Research
Christopher D. Cappa
Christopher D. Cappa University of California, Davis
Manvendra K. Dubey
Manvendra K. Dubey Los Alamos National Laboratory

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