A5018176345- Atmospheric Ozone and Climate
- Atmospheric chemistry and aerosols
- Atmospheric and Environmental Gas Dynamics
- Climate variability and models
- Atmospheric aerosols and clouds
- Meteorological Phenomena and Simulations
- Ionosphere and magnetosphere dynamics
- Ocean Acidification Effects and Responses
- Isotope Analysis in Ecology
- Lightning and Electromagnetic Phenomena
- Marine and coastal ecosystems
- Maritime Transport Emissions and Efficiency
- Spectroscopy and Chemometric Analyses
- Air Quality and Health Impacts
- Air Quality Monitoring and Forecasting
- Tropical and Extratropical Cyclones Research
- Geological and Geophysical Studies
- Soil Moisture and Remote Sensing
- Icing and De-icing Technologies
- Freshwater macroinvertebrate diversity and ecology
- Aquatic Ecosystems and Phytoplankton Dynamics
- Geochemistry and Geologic Mapping
- Plant responses to elevated CO2
- Aquatic and Environmental Studies
- Fire effects on ecosystems
NSF National Center for Atmospheric Research
2016-2025
National Research Council
2025
South Dakota School of Mines and Technology
2009-2013
Abstract The Deep Convective Clouds and Chemistry (DC3) field experiment produced an exceptional dataset on thunderstorms, including their dynamical, physical, electrical structures impact the chemical composition of troposphere. gathered detailed information inflow outflow regions midlatitude thunderstorms in northeast Colorado, west Texas to central Oklahoma, northern Alabama. A unique aspect DC3 strategy was locate sample convective a day after active convection order measure...
Abstract Chemical transport associated with the dynamics of Asian summer monsoon (ASM) system is investigated using model output from National Center for Atmospheric Research (NCAR) Whole Atmosphere Community Climate Model run in specified mode. The 3‐D day‐to‐day behavior modeled carbon monoxide analyzed together dynamical fields and boundaries to identify preferred locations uplifting boundary layer, role subseasonal‐scale upper troposphere lower stratosphere (UTLS), relationship ASM...
Abstract The transport of air from the planetary boundary layer (PBL) into Asian Summer Monsoon anticyclone is investigated using backward trajectories initiated within anti‐cyclone at 100 mb and 200 during August 2011. Transport occurs through a well‐defined conduit centered over southern Tibetan plateau, where convection lofts parcels anticyclone. conduit, as dynamical feature, distinct Thus, while influences upper troposphere lower stratosphere, it does not by itself define pipeline that...
Abstract The Convective Transport of Active Species in the Tropics (CONTRAST) experiment was conducted from Guam (13.5°N, 144.8°E) during January–February 2014. Using NSF/NCAR Gulfstream V research aircraft, investigated photochemical environment over tropical western Pacific (TWP) warm pool, a region massive deep convection and major pathway for air to enter stratosphere Northern Hemisphere (NH) winter. new observations provide wealth information quantifying influence on vertical...
Abstract. Every year during the Asian summer monsoon season from about mid-June to early September, a stable anticyclonic circulation system forms over Himalayas. This (ASM) anticyclone has been shown promote transport of air into stratosphere troposphere, which contains large amounts anthropogenic pollutants. Essential details transport, such as exact timescales vertical role convection in cross-tropopause exchange, and main location level export confined are still not fully resolved....
Abstract Refractory black carbon (rBC) is a primary aerosol species, produced through incomplete combustion, that absorbs sunlight and contributes to positive radiative forcing. The overall climate effect of rBC depends on its spatial distribution atmospheric lifetime, both which are impacted by the efficiency with transported or removed convective systems. These processes poorly constrained observations. It especially interesting investigate transport Asian Summer Monsoon (ASM) since this...
Abstract A significant source of ozone in the troposphere is transport from stratosphere. The stratospheric contribution has been estimated mainly using global models that attribute process largely to global‐scale Brewer‐Dobson circulation and synoptic‐scale dynamics associated with upper tropospheric jet streams. We report observations research aircraft reveal additional ozone‐rich air downward into by a leading‐line‐trailing‐stratiform mesoscale convective system convection overshooting...
Abstract The Southern Ocean plays a critical role in the global climate system by mediating atmosphere–ocean partitioning of heat and carbon dioxide. However, Earth models are demonstrably deficient Ocean, leading to large uncertainties future air–sea CO2 flux projections under warming incomplete interpretations natural variability on interannual geologic time scales. Here, we describe recent aircraft observational campaign, O2/N2 Ratio Airborne (ORCAS) study, which collected measurements...
Abstract Acetone is one of the most abundant oxygenated volatile organic compounds (VOCs) in atmosphere. The oceans impose a strong control on atmospheric acetone, yet oceanic fluxes acetone remain poorly constrained. In this work, global budget evaluated using two models: CAM‐chem and GEOS‐Chem. uses an online air‐sea exchange framework to calculate bidirectional fluxes, which coupled data‐oriented machine‐learning approach. algorithm trained suite seawater measurements. GEOS‐Chem fixed...
Abstract In situ and remote sensing observations of water vapor are analyzed to assess the evidence for direct convective hydration lower stratosphere. We have examined several hundred balloon‐borne airborne in measurements stratospheric humidity tropics northern midlatitudes. find that tropical H 2 O enhancements above background occur quite infrequently, height is within about 1 km cold‐point tropopause. Following Schwartz et al. (2013, https://doi.org/10.1002/grl.50421 ), we examine...
Abstract The subseasonal scale dynamics of the Asian summer monsoon (ASM) upper troposphere (UT) anticyclone has been identified as a primary mechanism for convectively lofted boundary layer air to leave confinement and impact global UT lower stratosphere (UTLS). This work quantifies eastward eddy shedding associated with oscillation chemical transport. Using reanalysis data together satellite trace gas data, we examine correlation between enhanced tropospheric species presence secondary...
Deep convection in the Asian summer monsoon is a significant transport process for lifting pollutants from planetary boundary layer to tropopause level. This enables efficient injection into stratosphere of reactive species such as chlorinated very short-lived substances (Cl-VSLSs) that deplete ozone. Past studies convective associated with have focused mostly on south monsoon. Airborne observations reported this work identify East an effective pathway carried record-breaking levels...
We present a method of identifying the tropical tropopause transition layer (TTL) using chemical tracer-tracer relationships. Coincident ozone (O3) and water vapor (H2O) measurements over Alajuela, Costa Rica (~10°N), in July August 2007 are used to demonstrate concept. In space, O3 H2O relationship helps separate air mass from background troposphere stratosphere. This tracer relationship-based is found span an approximately 40 K potential temperature range between 340 380 largely confined...
Abstract. We report measurements of bromine monoxide (BrO) and use an observationally constrained chemical box model to infer total gas-phase inorganic (Bry) over the tropical western Pacific Ocean (tWPO) during CONTRAST field campaign (January–February 2014). The observed BrO inferred Bry profiles peak in marine boundary layer (MBL), suggesting need for a source from sea-salt aerosol (SSA), addition organic (CBry). Both are found be C-shaped with local maxima upper free troposphere (FT)....
Abstract Although the tropopause is a well‐established concept, its definition and physical properties remain an active research topic. In tropics, both World Meteorological Organization established lapse rate minimum in temperature profile (the cold point) are used to determine height. We examine differences produced by these two definitions using high‐resolution airborne situ measurements of temperature, water vapor, ozone tropical layer from recent experiment over western Pacific National...
[1] In recent decades, the diatom Didymosphenia geminata has emerged as nuisance species in river systems around world. This periphytic alga forms large "blooms" temperate streams, presenting a counterintuitive result: blooms occur primarily oligotrophic streams and rivers, where phosphorus (P) availability typically limits primary production. The goal of this study is to examine how high algal biomass formed under low P conditions. We reveal biogeochemical process by which D. mats...
Abstract The Asian summer monsoon (ASM) as a chemical transport system is investigated using suite of models in preparation for an airborne field campaign over the Western Pacific. Results show that dynamical process anticyclone eddy shedding upper troposphere rapidly transports convectively uplifted boundary layer air masses to and lower stratosphere transported contain significantly enhanced aerosol loading complex mixture trace gases are relevant ozone chemistry. forecast consistently...
Abstract. Lagrangian modeling of transport, as implemented in the Chemical Model Stratosphere (CLaMS), connects advective (reversible) component transport along 3D trajectories with mixing, irreversible component. Here, we investigate interplay between strongly localized convective uplifts and large-scale flow dynamics upper troposphere lower stratosphere (UTLS). We revisit formulation convection CLaMS-3.0/MESSy, driven by ECMWF’s ERA5 reanalysis, further develop model. These developments...
Abstract This study investigates the sources and regional attributions of nitrogen oxides (NO x ) in upper troposphere|upper tropospheric (UT) during Asian Summer Monsoon (ASM). The importance South Asia (SA) East (EA) contributions is subject main interest. Using artificial tracers a chemistry‐climate model, simulations with from surface anthropogenic lightning SA EA are conducted. Model results validated airborne observations Chemical Climate Impact Project (ACCLIP) campaign 2022 over West...
Abstract The Asian Summer Monsoon (ASM) has garnered attention in recent years for its impacts on the composition of upper troposphere and lower stratosphere (UTLS) via deep convection. A observational effort into this mechanism, Chemical CLimate Impact Project (ACCLIP), sampled ASM UTLS over northwestern Pacific region during boreal summer 2022 using two airborne platforms. In work, we integrate Lagrangian trajectory modeling with convective cloud top observations to diagnose transport...
Abstract Hydroxyl radical (OH) is the main daytime oxidant in troposphere and determines atmospheric lifetimes of many compounds. We use aircraft measurements O 3 , H 2 O, NO, other species from Convective Transport Active Species Tropics (CONTRAST) field campaign, which occurred tropical western Pacific (TWP) during January–February 2014, to constrain a photochemical box model estimate concentrations OH throughout troposphere. find that tropospheric column (OH COL ) inferred CONTRAST...
Abstract Ice supersaturation (ISS) is the prerequisite condition for cirrus cloud formation. To examine multiscale dynamics' influences on ISS formation, we analyze in situ aircraft observations (~200 m scale) over North America coordinates relative to dynamical boundaries upper troposphere and lower stratosphere. Two case studies demonstrate that formation likely influenced by mesoscale uplifting, small‐scale waves, turbulence. A collective analysis of 15 flights April–June 2008 shows top...
Abstract During the Deep Convective Clouds and Chemistry (DC3) experiment in summer 2012, airborne measurements were performed anvil inflow/outflow of thunderstorms over Central U.S. by three research aircraft. A general overview Deutsches Zentrum für Luft‐ und Raumfahrt (DLR)‐Falcon situ (CO, O 3 , SO 2 CH 4 NO, NO x black carbon) is presented. In addition, a joint flight on 29 May 2012 convective line isolated supercell storms Oklahoma described based Falcon, National Science...
Abstract. The Asian summer monsoon (ASM) creates a hemispheric-scale signature in trace-gas distributions the upper troposphere and lower stratosphere (UTLS). Data from satellite retrievals are best source of information for characterizing these large-scale signatures. Measurements Microwave Limb Sounder (MLS), limb-viewing sensor, have been most widely used retrieval products types studies. This work explores ASM influence on UTLS chemical distribution two nadir-viewing sensors, Infrared...
Abstract Unique in situ measurements of CO, O 3 , SO 2 CH 4 NO, NO x y VOC, CN, and rBC were carried out with the German Deutsches Zentrum für Luft‐ und Raumfahrt (DLR)‐Falcon aircraft central U.S. thunderstorms during Deep Convective Clouds Chemistry experiment summer 2012. Fresh aged anvil outflow (9–12 km) from supercells, mesoscale convective systems, complexes, squall lines probed over Oklahoma, Texas, Colorado, Kansas. For three case studies (30 May 8 12 June) a combination trace...