A5035378981- Atmospheric chemistry and aerosols
- Atmospheric Ozone and Climate
- Atmospheric and Environmental Gas Dynamics
- Wind and Air Flow Studies
- Meteorological Phenomena and Simulations
- Air Quality and Health Impacts
- Atmospheric aerosols and clouds
- Fire dynamics and safety research
- Peatlands and Wetlands Ecology
- Air Quality Monitoring and Forecasting
- Isotope Analysis in Ecology
- Marine and coastal ecosystems
- Soil Carbon and Nitrogen Dynamics
- Geology and Paleoclimatology Research
- Microbial Community Ecology and Physiology
- Aeolian processes and effects
- Paleontology and Stratigraphy of Fossils
- Climate variability and models
- Soil erosion and sediment transport
- Geological and Geochemical Analysis
- Geochemistry and Elemental Analysis
- Soil and Water Nutrient Dynamics
- Groundwater and Isotope Geochemistry
- Ocean Acidification Effects and Responses
- Plant Micronutrient Interactions and Effects
University of Colorado Boulder
2022-2025
University of Colorado System
2025
Institute of Arctic and Alpine Research
2023-2024
NOAA Oceanic and Atmospheric Research
2024
National Oceanic and Atmospheric Administration
2022-2023
Cooperative Institute for Research in Environmental Sciences
2022-2023
Purdue University West Lafayette
2018-2023
University of Science and Technology of China
2020
University of Alberta
2014-2017
Purdue University System
2017
Secondary sulfate aerosols played an important role in aerosol formation and aging processes, especially during haze episodes China. was formed via atmospheric oxidation of SO2 by OH, O3, H2O2, transition-metal-catalyzed (TMI) O2. However, the relative importance these oxidants strongly debated. Here, we use stable sulfur isotopes (δ34S) a Rayleigh distillation model to quantify contributions each oxidant episode Nanjing, megacity The observed δ34S values showed negative correlation with...
Abstract The Hunga Tonga‐Hunga Ha'apai (HTHH) volcanic eruption in January 2022 injected unprecedented amounts of water vapor (H 2 O) and a moderate amount the aerosol precursor sulfur dioxide (SO ) into Southern Hemisphere (SH) tropical stratosphere. H O perturbations have persisted during early 2023 dispersed throughout atmosphere. Observations show large‐scale SH stratospheric cooling, equatorward shift Antarctic polar vortex slowing Brewer‐Dobson circulation. Satellite observations...
Abstract Inorganic nitrate production is critical in atmospheric chemistry that reflects the oxidation capacity and acidity of atmosphere. Here we use oxygen anomaly (Δ 17 O( $$\rm{NO}_{3}^{-}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msubsup><mml:mrow><mml:mi>NO</mml:mi></mml:mrow><mml:mrow><mml:mn>3</mml:mn></mml:mrow><mml:mrow><mml:mo>−</mml:mo></mml:mrow></mml:msubsup></mml:math> )) high-time-resolved (3 h) aerosols to explore chemical mechanisms evolution fine...
Sulfate (SO42–) is an important chemical species in atmospheric aerosols, which strongly impacts chemistry processes and climate change. Stable sulfur isotopes (δ34S) of sulfate aerosols PM2.5 were measured Beijing from November 13 to December 2, 2018, investigate the pathways formation aerosols. The results showed that SO42– constituted a major fraction (18%) water-soluble ions significant enhancement was observed during haze period. δ34S-SO42– values averaged at 4.4 ± 1.4‰ full period,...
Abstract Inorganic nitrate (NO 3 − ) is a crucial component of fine particulate matter (PM 2.5 in haze events China. Understanding the formation mechanisms and sources NO x was critical to control air pollution. In this study, measurements multiple isotope compositions (δ 18 O‐NO , δ 17 15 N‐NO PM were conducted Hangzhou from 9 October 2015 24 August 2016. Our results showed that oxygen anomaly (Δ : 20.0‰–37.9‰) nitrogen −2.9‰ 18.1‰) values higher winter lower summer. Based on Δ observation...
Abstract. In the face of ongoing and projected climatic changes, precipitation manipulation experiments (PMEs) have produced a wealth data about effects changes on soils. response, researchers undertaken number synthetic efforts. Several meta-analyses been conducted, each revealing new aspects soil responses to changes. Here, we conducted comparative analysis findings 16 focused 42 response variables, covering wide range processes. We examine individual variables as well more integrative...
Abstract. Nitrogen isotope fractionations between nitrogen oxides (NO and NO2) play a significant role in determining the isotopic compositions (δ15N) of atmospheric reactive nitrogen. Both equilibrium exchange NO NO2 molecules effects occurring during NOx photochemical cycle are important, but both not well constrained. The nighttime daytime an simulation chamber at atmospherically relevant levels were measured. Then, impact level photolysis rate on combined fractionation (equilibrium...
High sulfur emissions in the Central Andes have past been attributed to active volcanoes and numerous copper smelting facilities region. This study evaluates contribution of these sources on Arequipa, Peru through an evaluation aerosol sulfate δ34S values water-soluble ions (WSI). The anthropogenic natural particulate pollution were determined by filter sampling from four different locations (urban, suburban, industrial, rural) providing a view spatial variability aerosols within city....
Abstract Marine sulfate aerosols in the Southern Ocean are critical to global radiation balance, yet sources of and their seasonal variations unclear. We separately sampled marine ambient at Baring Head, New Zealand for 1 year using two collectors evaluated coarse (1–10 μm) fine (0.05–1 sulfur isotopes (δ 34 S). In both collectors, sea‐salt (SO 4 2− SS ) mainly existed nonsea‐salt NSS dominated aerosols, although some summer SO appeared particles due aerosol coagulation. was (88–100%) from...
In a complex environment such as an urban area, accurate prediction of the atmospheric dispersion airborne harmful materials radioactive substances is necessary for establishing response actions and assessing risk or damage. Given variety models available, evaluation inter-comparison exercises are vital quantitatively qualitatively their capabilities differences. To that end, European Commission/Directorate General Joint Research Centre with support from General-Migration Home Affairs,...
Soils in ice-free areas Antarctica are recognized for their high salt concentrations and persistent arid conditions. While previous studies have investigated the distribution of salts potential sources McMurdo Dry Valleys, logistical constraints limited our investigation understanding dynamics within Transantarctic Mountains. We focused on Shackleton Glacier (85° S, 176° W), a major outlet glacier East Antarctic Ice Sheet located Central Mountains (CTAM), collected surface soil samples from...
The growth rate of the atmospheric abundance methane (CH 4 ) reached a record high 15.4 ppb yr −1 between 2020 and 2022, but mechanisms driving accelerated CH have so far been unclear. In this work, we use measurements 13 C: 12 C ratio (expressed as δ CH4 from NOAA’s Global Greenhouse Gas Reference Network box model to investigate potential drivers for rapid growth. These show that record-high in 2020–2022 was accompanied by sharp decline , indicating increase mainly driven increased...
Abstract. The age of air is an important transport diagnostic that can be derived from trace gas measurements and compared to global chemistry climate model output. We describe a new technique calculate the air, measuring times Earth's surface any location in atmosphere based on simultaneous situ multiple key long-lived gases. primary benefits this include (1) optimized ages consistent with simultaneously measured SF6 CO2; (2) upper troposphere through stratosphere; (3) estimates second...
The Hunga Tonga-Hunga Ha'apai (HTHH) volcanic eruption in January 2022 injected extreme amounts of water vapor (H2O) and a moderate amount the aerosol precursor (SO2) into Southern Hemisphere (SH) stratosphere. H2O perturbations have persisted resulted large-scale SH stratospheric cooling, equatorward shift Antarctic polar vortex, slowing Brewer-Dobson circulation associated with substantial ozone reduction winter midlatitudes. Chemistry-climate model simulations forced by realistic HTHH...
The capabilities of nine atmospheric dispersion models in predicting near-field from puff releases an urban environment are addressed under the Urban Dispersion INternational Evaluation Exercise (UDINEE) project. model results evaluated using tracer observations Joint 2003 (JU2003) experiment where neutrally-buoyant puffs were released downtown area Oklahoma City, USA. Sulphur hexafluoride concentration time series measured at ten sampling locations during four daytime and night-time used to...
In paddy soils, iron (Fe) forms are highly influenced by the seasonal redox changes and leave detectable isotope signals because of fractionation between different Fe forms. Here, we present concentrations compositions (expressed as δ56Fe values) in a soil profile from Suzhou, China. Light isotopes were enriched two iron-accumulation layers (Br3 G1) with high concentrations. particular, large shifts both values found at Br2 Br3 boundaries, showing fast efficient transformation these...