A5046972707- Atmospheric chemistry and aerosols
- Atmospheric Ozone and Climate
- Air Quality and Health Impacts
- Atmospheric and Environmental Gas Dynamics
- Atmospheric aerosols and clouds
- Air Quality Monitoring and Forecasting
- Climate variability and models
- Vehicle emissions and performance
- Geophysics and Gravity Measurements
- Fire effects on ecosystems
- Medical Imaging Techniques and Applications
- Geochemistry and Geologic Mapping
- Groundwater and Isotope Geochemistry
- Geology and Paleoclimatology Research
- Climate Change and Health Impacts
- Cryospheric studies and observations
- Water Quality and Pollution Assessment
- Atomic and Subatomic Physics Research
- Free Radicals and Antioxidants
- Lattice Boltzmann Simulation Studies
- Advanced Data Storage Technologies
- Chronic Obstructive Pulmonary Disease (COPD) Research
- Gas Dynamics and Kinetic Theory
- Odor and Emission Control Technologies
- Heavy metals in environment
Seoul National University of Education
2024-2025
NSF National Center for Atmospheric Research
2020-2024
Seoul National University
2013-2024
National Oceanic and Atmospheric Administration
2024
Atmospheric Chemistry Observations & Modeling
2021-2023
Cooperative Institute for Research in Environmental Sciences
2017-2022
University of Colorado Boulder
2017-2022
University of Colorado System
2019
Abstract. Recent laboratory studies suggest that secondary organic aerosol (SOA) formation rates are higher than assumed in current models. There is also evidence SOA removal by dry and wet deposition occurs more efficiently some models photolysis heterogeneous oxidation may be important (but currently ignored) sinks. Here, we have updated the global GEOS-Chem model to include this new information on (i.e., wall-corrected yields emissions of semi-volatile intermediate volatility compounds)...
Abstract. Recent observations suggest that a certain fraction of organic carbon (OC) aerosol effectively absorbs solar radiation, which is also known as brown (BrC) aerosol. Despite much observational evidence its presence, very few global modelling studies have been conducted because poor understanding BrC emissions. Here we present an explicit simulation in 3-D chemical transport model (GEOS-Chem), including emission estimates from primary (3.9 ± 1.7 and 3.0 1.3 TgC yr−1 biomass burning...
Abstract. Anthropogenic secondary organic aerosol (ASOA), formed from anthropogenic emissions of compounds, constitutes a substantial fraction the mass submicron in populated areas around world and contributes to poor air quality premature mortality. However, precursor sources ASOA are poorly understood, there large uncertainties health benefits that might accrue reducing emissions. We show production 11 urban on three continents is strongly correlated with reactivity specific volatile...
Abstract. Aerosol indirect radiative forcing (IRF), which characterizes how aerosols alter cloud formation and properties, is very sensitive to the preindustrial (PI) aerosol burden. Dimethyl sulfide (DMS), emitted from ocean, a dominant natural precursor of non-sea-salt sulfate in PI pristine present-day (PD) atmospheres. Here we revisit atmospheric oxidation chemistry DMS, particularly under conditions, its impact on IRF. Based previous laboratory studies, expand simplified DMS scheme used...
A new configuration of the Community Earth System Model (CESM)/Community Atmosphere with full chemistry (CAM-chem) supporting capability horizontal mesh refinement through use spectral element (SE) dynamical core is developed and called CESM/CAM-chem-SE. Horizontal in CESM/CAM-chem-SE unique novel that pollutants such as ozone are accurately represented at human exposure relevant scales while also directly including global feedbacks. down to ∼14 km over conterminous US (CONUS) beginning...
Abstract. The spatial distribution and properties of submicron organic aerosol (OA) are among the key sources uncertainty in our understanding effects on climate. Uncertainties particularly large over remote regions free troposphere Southern Ocean, where very few data have been available OA predictions from AeroCom Phase II global models span 2 to 3 orders magnitude, greatly exceeding model spread source regions. (nearly) pole-to-pole vertical non-refractory aerosols was measured with an...
Abstract The inorganic fraction of fine particles affects numerous physicochemical processes in the atmosphere. However, there is large uncertainty its burden and composition due to limited global measurements. Here, we present observations from eleven different aircraft campaigns around globe investigate how aerosol pH ammonium balance change polluted remote regions, such as over oceans. Both parameters show increasing acidity with remoteness, at all altitudes, decreasing about 3 −1 almost...
Abstract. The recent update on the US National Ambient Air Quality Standards (NAAQS) of ground-level ozone (O3) can benefit from a better understanding its source contributions in different regions during years. In Hemispheric Transport Pollution experiment phase 1 (HTAP1), various global models were used to determine O3 source–receptor (SR) relationships among three continents Northern Hemisphere 2001. support HTAP 2 (HTAP2) that studies more years and involves higher-resolution regional...
Key Points Aerosol absorption is sensitive to mixing state, brown carbon, and soil dust optical properties Blanching reduces coating carbon radiative effect; effect uncertainty due the refractive index large Radiative of radiation‐absorbing aerosol total mainly treatment
Abstract. Secondary organic aerosol derived from isoprene epoxydiols (IEPOX-SOA) is thought to contribute the dominant fraction of total SOA, but current volatility-based lumped SOA parameterizations are not appropriate represent reactive uptake IEPOX onto acidified aerosols. A full explicit modeling this chemistry however computationally expensive owing many species and reactions tracked, which makes it difficult include in chemistry–climate models for long-term studies. Here we present...
Abstract. Secondary organic aerosol (SOA) is a dominant contributor of fine particulate matter in the atmosphere, but complexity SOA formation chemistry hinders accurate representation models. Volatility-based parameterizations have been adopted many recent modeling studies and shown reasonable performance compared to observations. However, assumptions made these empirical can lead substantial errors when applied future climatic conditions as they do not include mechanistic understanding...
Abstract Model intercomparison studies often report a large spread in simulation results, but quantifying the causes of these differences is hindered by fact that several processes contribute to model simultaneously. Here we use Multi‐Scale Infrastructure for Chemistry and Aerosols (MUSICA) version 0 investigate resolution dependencies simulated chemical species, with focus on between global uniform grid regional refinement simulations same modeling framework. We construct two (ne30 [∼112...
South Korea has recently achieved developed country status with the second largest megacity in world, Seoul Metropolitan Area (SMA). This study provides insights into future changes air quality for rapidly emerging megacities East Asian region. We present total OH reactivity observations SMA conducted at an urban site (May–June, 2015) and a suburban forest (Sep, 2015). The during daytime was observed similar levels (∼15 s<sup>−1</sup>) to those previously reported from other studies. Trace...
Abstract The Asian Tropopause Aerosol Layer (ATAL) represents an accumulation of aerosol in the upper troposphere and lower stratosphere associated with Summer Monsoon. Here we simulate ATAL for summer 2013 GEOS‐Chem chemical transport model explore likely composition aerosols relative contributions regional anthropogenic sources versus those from farther afield. indicates significant organic aerosol, nitrate, sulfate, ammonium precursor dominant. underestimates backscatter during 2013,...
The impact of aerosols on human health and climate is well-recognized, yet many studies have only focused total PM2.5 or changes from anthropogenic activities. This study quantifies the effects organic (OA) anthropogenic, biomass burning, biogenic sources. Using two atmospheric chemistry models, CAM-chem GEOS-Chem, our findings reveal that primary OA (POA) has highest efficiency for but lowest direct radiative due to spatial temporal variations associated with population surface albedo....
Abstract. Recent laboratory studies suggest that secondary organic aerosol (SOA) formation rates are higher than assumed in current models. There is also evidence SOA removal by dry and wet deposition occurs more efficiently some models suggest, photolysis heterogeneous oxidation may be important (but currently ignored) sinks. Here, we have updated the global GEOS-Chem model to include this new information on (i.e. wall-corrected yields emissions of semi-volatile intermediate volatility...
We report aircraft observations of extreme levels HCl and the dihalogens Cl2, Br2, BrCl in an industrial plume near Great Salt Lake, Utah. Complete depletion O3 was observed concurrently with halogen enhancements as a direct result photochemically produced radicals. Observed fluxes for HCl, NOx agreed facility-reported emissions inventories. Bromine are not required to be reported inventory, but estimated 173 Mg year-1 Br2 949 BrCl, representing major uncounted oxidant source. A...
Abstract Observed surface organic aerosols (OA) concentrations slightly increased in the western US (WUS) but significantly decreased eastern (EUS) summer, and continuously winter over region. To understand driving factors for long‐term OA trend, we apply a revised version of Community Atmosphere Model 6 with comprehensive tropospheric stratospheric chemistry representation, considering heterogeneous formation isoprene‐epoxydiol‐derived secondary (SOAIE) fast photolysis rate...
Abstract. The Geostationary Environment Monitoring Spectrometer (GEMS) over Asia is the first geostationary Earth orbit instrument in virtual constellation of sensors for atmospheric chemistry and composition air quality research applications. For time, hourly observations enable studies diurnal variation several important trace gas aerosol pollutants including nitrogen dioxide (NO2), which focus this work. NO2 a regulated pollutant an indicator anthropogenic emissions addition to being...
Abstract. Highly oxygenated organic molecules (HOMs) can significantly contribute to new particle formation (NPF). HOMs-derived NPF in preindustrial (PI) environments provides the baseline for calculating radiative forcing, yet global model studies examining this are lacking. Here, we use a climate with semi-explicit HOMs chemistry and associated nucleation scheme systematically quantify effect of on CCN effective forcing due aerosol–cloud interactions (ERFaci). The improved shows better...
Abstract. Surface ozone (O3) in Southeast Michigan (SEMI) often exceeds U.S. National Ambient Air Quality Standards, posing risks to human health and agroecosystems. SEMI, a relatively small region the state of Michigan, contains most state’s anthropogenic emission sources more than half population, is also prone long-range transboundary pollutant transport. Here, we explore distribution O3 its precursors, such as nitrogen oxides (NOx) volatile organic compounds, over SEMI during summer 2021...
Fires in the wildland-urban interface (WUI) are a global issue with growing importance. However, impact of WUI fires on air quality and health is less understood compared to that wildland. We analyze fire impacts at scale using multi-scale atmospheric chemistry model—the Multi-Scale Infrastructure for Chemistry Aerosols model (MUSICA). have notable key pollutants [e.g., carbon monoxide (CO), nitrogen dioxide (NO 2 ), fine particulate matter (PM 2.5 ozone (O 3 )]. The emission...