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Gretchen L. Mullendore
,
Mary C. Barth
,
Petra M. Klein
, and
James H. Crawford

Abstract

Historically, atmospheric field campaigns typically focused on either meteorology or chemistry with very limited complementary observations from the other discipline. In contrast, a growing number of researchers are working across subdisciplines to include meteorological and chemical measurements when planning field campaigns to increase the value of the collected datasets for subsequent analyses. Including select trace gas measurements should be intrinsic to certain dynamics campaigns, as they can add insights into dynamical processes. This paper highlights the mutual benefits of joint dynamics–chemistry campaigns by reporting on a small sample of examples across a broad range of meteorological scales to demonstrate the value of this strategy, with focus on the Deep Convective Clouds and Chemistry (DC3) campaign as a recent example. General recommendations are presented as well as specific recommendations of chemical species appropriate for a range of meteorological temporal and spatial scales.

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Christopher P. Loughner
,
Maria Tzortziou
,
Melanie Follette-Cook
,
Kenneth E. Pickering
,
Daniel Goldberg
,
Chinmay Satam
,
Andrew Weinheimer
,
James H. Crawford
,
David J. Knapp
,
Denise D. Montzka
,
Glenn S. Diskin
, and
Russell R. Dickerson

Abstract

Meteorological and air-quality model simulations are analyzed alongside observations to investigate the role of the Chesapeake Bay breeze on surface air quality, pollutant transport, and boundary layer venting. A case study was conducted to understand why a particular day was the only one during an 11-day ship-based field campaign on which surface ozone was not elevated in concentration over the Chesapeake Bay relative to the closest upwind site and why high ozone concentrations were observed aloft by in situ aircraft observations. Results show that southerly winds during the overnight and early-morning hours prevented the advection of air pollutants from the Washington, D.C., and Baltimore, Maryland, metropolitan areas over the surface waters of the bay. A strong and prolonged bay breeze developed during the late morning and early afternoon along the western coastline of the bay. The strength and duration of the bay breeze allowed pollutants to converge, resulting in high concentrations locally near the bay-breeze front within the Baltimore metropolitan area, where they were then lofted to the top of the planetary boundary layer (PBL). Near the top of the PBL, these pollutants were horizontally advected to a region with lower PBL heights, resulting in pollution transport out of the boundary layer and into the free troposphere. This elevated layer of air pollution aloft was transported downwind into New England by early the following morning where it likely mixed down to the surface, affecting air quality as the boundary layer grew.

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Mary C. Barth
,
Christopher A. Cantrell
,
William H. Brune
,
Steven A. Rutledge
,
James H. Crawford
,
Heidi Huntrieser
,
Lawrence D. Carey
,
Donald MacGorman
,
Morris Weisman
,
Kenneth E. Pickering
,
Eric Bruning
,
Bruce Anderson
,
Eric Apel
,
Michael Biggerstaff
,
Teresa Campos
,
Pedro Campuzano-Jost
,
Ronald Cohen
,
John Crounse
,
Douglas A. Day
,
Glenn Diskin
,
Frank Flocke
,
Alan Fried
,
Charity Garland
,
Brian Heikes
,
Shawn Honomichl
,
Rebecca Hornbrook
,
L. Gregory Huey
,
Jose L. Jimenez
,
Timothy Lang
,
Michael Lichtenstern
,
Tomas Mikoviny
,
Benjamin Nault
,
Daniel O’Sullivan
,
Laura L. Pan
,
Jeff Peischl
,
Ilana Pollack
,
Dirk Richter
,
Daniel Riemer
,
Thomas Ryerson
,
Hans Schlager
,
Jason St. Clair
,
James Walega
,
Petter Weibring
,
Andrew Weinheimer
,
Paul Wennberg
,
Armin Wisthaler
,
Paul J. Wooldridge
, and
Conrad Ziegler

Abstract

The Deep Convective Clouds and Chemistry (DC3) field experiment produced an exceptional dataset on thunderstorms, including their dynamical, physical, and electrical structures and their impact on the chemical composition of the troposphere. The field experiment gathered detailed information on the chemical composition of the inflow and outflow regions of midlatitude thunderstorms in northeast Colorado, west Texas to central Oklahoma, and northern Alabama. A unique aspect of the DC3 strategy was to locate and sample the convective outflow a day after active convection in order to measure the chemical transformations within the upper-tropospheric convective plume. These data are being analyzed to investigate transport and dynamics of the storms, scavenging of soluble trace gases and aerosols, production of nitrogen oxides by lightning, relationships between lightning flash rates and storm parameters, chemistry in the upper troposphere that is affected by the convection, and related source characterization of the three sampling regions. DC3 also documented biomass-burning plumes and the interactions of these plumes with deep convection.

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David A. Peterson
,
Laura H. Thapa
,
Pablo E. Saide
,
Amber J. Soja
,
Emily M. Gargulinski
,
Edward J. Hyer
,
Bernadett Weinzierl
,
Maximilian Dollner
,
Manuel Schöberl
,
Philippe P. Papin
,
Shobha Kondragunta
,
Christopher P. Camacho
,
Charles Ichoku
,
Richard H. Moore
,
Johnathan W. Hair
,
James H. Crawford
,
Philip E. Dennison
,
Olga V. Kalashnikova
,
Christel E. Bennese
,
Thaopaul P. Bui
,
Joshua P. DiGangi
,
Glenn S. Diskin
,
Marta A. Fenn
,
Hannah S. Halliday
,
Jose Jimenez
,
John B. Nowak
,
Claire Robinson
,
Kevin Sanchez
,
Taylor J. Shingler
,
Lee Thornhill
,
Elizabeth B. Wiggins
,
Edward Winstead
, and
Chuanyu Xu

Abstract

The 2019 Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) field experiment obtained a diverse set of in situ and remotely sensed measurements before and during a pyrocumulonimbus (pyroCb) event over the Williams Flats fire in Washington State. This unique dataset confirms that pyroCb activity is an efficient vertical smoke transport pathway into the upper troposphere and lower stratosphere (UTLS). The magnitude of smoke plumes observed in the UTLS has increased significantly in recent years, following unprecedented wildfire and pyroCb activity observed worldwide. The FIREX-AQ pyroCb dataset is therefore extremely relevant to a broad community, providing the first measurements of fresh smoke exhaust in the upper troposphere, including from within active pyroCb cloud tops. High-resolution remote sensing reveals that three plume cores linked to localized fire fronts, burning primarily in dense forest fuels, contributed to four total pyroCb “pulses.” Rapid changes in fire geometry and spatial extent dramatically influenced the magnitude, behavior, and duration of pyroCb activity. Cloud probe measurements and weather radar identify the presence of large ice particles within the pyroCb and hydrometers below cloud base, indicating precipitation development. The resulting feedbacks suggest that vertical smoke transport efficiency was reduced slightly when compared with intense pyroCb events reaching the lower stratosphere. Physical and optical aerosol property measurements in pyroCb exhaust are compared with previous assumptions. A large suite of aerosol and gas-phase chemistry measurements sets a foundation for future studies aimed at understanding the composition of smoke plumes lifted by pyroconvection into the UTLS and their role in the climate system.

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Janet Barlow
,
Martin Best
,
Sylvia I. Bohnenstengel
,
Peter Clark
,
Sue Grimmond
,
Humphrey Lean
,
Andreas Christen
,
Stefan Emeis
,
Martial Haeffelin
,
Ian N. Harman
,
Aude Lemonsu
,
Alberto Martilli
,
Eric Pardyjak
,
Mathias W Rotach
,
Susan Ballard
,
Ian Boutle
,
Andy Brown
,
Xiaoming Cai
,
Matteo Carpentieri
,
Omduth Coceal
,
Ben Crawford
,
Silvana Di Sabatino
,
Junxia Dou
,
Daniel R. Drew
,
John M. Edwards
,
Joachim Fallmann
,
Krzysztof Fortuniak
,
Jemma Gornall
,
Tobias Gronemeier
,
Christos H. Halios
,
Denise Hertwig
,
Kohin Hirano
,
Albert A. M. Holtslag
,
Zhiwen Luo
,
Gerald Mills
,
Makoto Nakayoshi
,
Kathy Pain
,
K. Heinke Schlünzen
,
Stefan Smith
,
Lionel Soulhac
,
Gert-Jan Steeneveld
,
Ting Sun
,
Natalie E Theeuwes
,
David Thomson
,
James A. Voogt
,
Helen C. Ward
,
Zheng-Tong Xie
, and
Jian Zhong
Open access
Nirnimesh Kumar
,
James A. Lerczak
,
Tongtong Xu
,
Amy F. Waterhouse
,
Jim Thomson
,
Eric J. Terrill
,
Christy Swann
,
Sutara H. Suanda
,
Matthew S. Spydell
,
Pieter B. Smit
,
Alexandra Simpson
,
Roland Romeiser
,
Stephen D. Pierce
,
Tony de Paolo
,
André Palóczy
,
Annika O’Dea
,
Lisa Nyman
,
James N. Moum
,
Melissa Moulton
,
Andrew M. Moore
,
Arthur J. Miller
,
Ryan S. Mieras
,
Sophia T. Merrifield
,
Kendall Melville
,
Jacqueline M. McSweeney
,
Jamie MacMahan
,
Jennifer A. MacKinnon
,
Björn Lund
,
Emanuele Di Lorenzo
,
Luc Lenain
,
Michael Kovatch
,
Tim T. Janssen
,
Sean R. Haney
,
Merrick C. Haller
,
Kevin Haas
,
Derek J. Grimes
,
Hans C. Graber
,
Matt K. Gough
,
David A. Fertitta
,
Falk Feddersen
,
Christopher A. Edwards
,
William Crawford
,
John Colosi
,
C. Chris Chickadel
,
Sean Celona
,
Joseph Calantoni
,
Edward F. Braithwaite III
,
Johannes Becherer
,
John A. Barth
, and
Seongho Ahn

Abstract

The inner shelf, the transition zone between the surfzone and the midshelf, is a dynamically complex region with the evolution of circulation and stratification driven by multiple physical processes. Cross-shelf exchange through the inner shelf has important implications for coastal water quality, ecological connectivity, and lateral movement of sediment and heat. The Inner-Shelf Dynamics Experiment (ISDE) was an intensive, coordinated, multi-institution field experiment from September–October 2017, conducted from the midshelf, through the inner shelf, and into the surfzone near Point Sal, California. Satellite, airborne, shore- and ship-based remote sensing, in-water moorings and ship-based sampling, and numerical ocean circulation models forced by winds, waves, and tides were used to investigate the dynamics governing the circulation and transport in the inner shelf and the role of coastline variability on regional circulation dynamics. Here, the following physical processes are highlighted: internal wave dynamics from the midshelf to the inner shelf; flow separation and eddy shedding off Point Sal; offshore ejection of surfzone waters from rip currents; and wind-driven subtidal circulation dynamics. The extensive dataset from ISDE allows for unprecedented investigations into the role of physical processes in creating spatial heterogeneity, and nonlinear interactions between various inner-shelf physical processes. Overall, the highly spatially and temporally resolved oceanographic measurements and numerical simulations of ISDE provide a central framework for studies exploring this complex and fascinating region of the ocean.

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Jhoon Kim
,
Ukkyo Jeong
,
Myoung-Hwan Ahn
,
Jae H. Kim
,
Rokjin J. Park
,
Hanlim Lee
,
Chul Han Song
,
Yong-Sang Choi
,
Kwon-Ho Lee
,
Jung-Moon Yoo
,
Myeong-Jae Jeong
,
Seon Ki Park
,
Kwang-Mog Lee
,
Chang-Keun Song
,
Sang-Woo Kim
,
Young Joon Kim
,
Si-Wan Kim
,
Mijin Kim
,
Sujung Go
,
Xiong Liu
,
Kelly Chance
,
Christopher Chan Miller
,
Jay Al-Saadi
,
Ben Veihelmann
,
Pawan K. Bhartia
,
Omar Torres
,
Gonzalo González Abad
,
David P. Haffner
,
Dai Ho Ko
,
Seung Hoon Lee
,
Jung-Hun Woo
,
Heesung Chong
,
Sang Seo Park
,
Dennis Nicks
,
Won Jun Choi
,
Kyung-Jung Moon
,
Ara Cho
,
Jongmin Yoon
,
Sang-kyun Kim
,
Hyunkee Hong
,
Kyunghwa Lee
,
Hana Lee
,
Seoyoung Lee
,
Myungje Choi
,
Pepijn Veefkind
,
Pieternel F. Levelt
,
David P. Edwards
,
Mina Kang
,
Mijin Eo
,
Juseon Bak
,
Kanghyun Baek
,
Hyeong-Ahn Kwon
,
Jiwon Yang
,
Junsung Park
,
Kyung Man Han
,
Bo-Ram Kim
,
Hee-Woo Shin
,
Haklim Choi
,
Ebony Lee
,
Jihyo Chong
,
Yesol Cha
,
Ja-Ho Koo
,
Hitoshi Irie
,
Sachiko Hayashida
,
Yasko Kasai
,
Yugo Kanaya
,
Cheng Liu
,
Jintai Lin
,
James H. Crawford
,
Gregory R. Carmichael
,
Michael J. Newchurch
,
Barry L. Lefer
,
Jay R. Herman
,
Robert J. Swap
,
Alexis K. H. Lau
,
Thomas P. Kurosu
,
Glen Jaross
,
Berit Ahlers
,
Marcel Dobber
,
C. Thomas McElroy
, and
Yunsoo Choi

Abstract

The Geostationary Environment Monitoring Spectrometer (GEMS) is scheduled for launch in February 2020 to monitor air quality (AQ) at an unprecedented spatial and temporal resolution from a geostationary Earth orbit (GEO) for the first time. With the development of UV–visible spectrometers at sub-nm spectral resolution and sophisticated retrieval algorithms, estimates of the column amounts of atmospheric pollutants (O3, NO2, SO2, HCHO, CHOCHO, and aerosols) can be obtained. To date, all the UV–visible satellite missions monitoring air quality have been in low Earth orbit (LEO), allowing one to two observations per day. With UV–visible instruments on GEO platforms, the diurnal variations of these pollutants can now be determined. Details of the GEMS mission are presented, including instrumentation, scientific algorithms, predicted performance, and applications for air quality forecasts through data assimilation. GEMS will be on board the Geostationary Korea Multi-Purpose Satellite 2 (GEO-KOMPSAT-2) satellite series, which also hosts the Advanced Meteorological Imager (AMI) and Geostationary Ocean Color Imager 2 (GOCI-2). These three instruments will provide synergistic science products to better understand air quality, meteorology, the long-range transport of air pollutants, emission source distributions, and chemical processes. Faster sampling rates at higher spatial resolution will increase the probability of finding cloud-free pixels, leading to more observations of aerosols and trace gases than is possible from LEO. GEMS will be joined by NASA’s Tropospheric Emissions: Monitoring of Pollution (TEMPO) and ESA’s Sentinel-4 to form a GEO AQ satellite constellation in early 2020s, coordinated by the Committee on Earth Observation Satellites (CEOS).

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