Meetings
UTLS Group Meetings
The NCAR/ACOM UTLS group will host weekly informal science discussions in summer / autumn 2024. Meetings are held in hybrid format, with in-person attendance in FL0-2108 or online using Google Meet (links are provided by email).
| Date | Speaker | Title / Topic |
|---|---|---|
| 2025 | ||
| Jan 7 | Colin Gurganus (NOAA CSL) | Analyzing the stratospheric sulfur budget during the 2023 SABRE campaign |
| Jan 21 | ||
| Jan 28 | ||
| Feb 4 | ||
| Feb 11 | ||
| Feb 18 | ||
| Feb 25 | ||
| Mar 4 | ||
| Mar 11 | ||
| 2024 | ||
| Aug 20 | Joowan Kim (Kongju National University, Korea) | Tropical tropopause processes in CCMI models: uncertainties and potential causes |
| Sept 3 | Emily Tinney (NCAR/ACOM) | The Response of Tropopause-Overshooting Convection over North America to Climate Change |
| Sept 17 | Ren Smith (NCAR/ACOM) | Transport by Asian Summer Monsoon Convection to the UTLS during ACCLIP (2022) |
| Oct 29 | Ewa Bednarz (NOAA) | Impacts of chlorinated very short lived species on halogen budget and stratospheric ozone over the recent past |
| Nov 12 | Amit Pandit (National Institute of Aerospace) | Investigating the role of typhoon-induced gravity waves and stratospheric hydration in the formation of tropopause cirrus clouds observed during the 2017 Asian monsoon |
| 2023 | ||
| Feb 9 | Bill Randel (NCAR/ACOM) | Recent changes to the stratospheric circulation (discussion of Plöger and Garny 2022) |
| Mar 2 | Paul Konopka (FZ Jülich) | Stratospheric Moistening after 2000 |
| Mar 9 | Ren Smith (NCAR/ACOM) | Evaluating the model representation of Asian monsoon UTLS transport and composition using StratoClim (2017) airborne in situ observations |
| Mar 23 | Jianghanyang Li (NOAA/CIRES) | A novel, cost-effective analytical method for measuring high-resolution vertical |
| Mar 30 | Katie Smith (U Miami) |
UTLS Whole Air Sampler Observations |
| Apr 13 | Carly KleinStern (U Chicago) | Temperature and Tracer Variations during the Overflight of Typhoon Hinnamnor |
| Apr 20 | Oliver Eppers (MPIC) | Chemical composition of aerosol particles associated with the Asian summer monsoon observed by ERICA |
| May 11 | Gregg Schill (NOAA/CSL) | PALMS-NG Observations from ACCLIP |
| June 15 | Qing Liang (NASA GSFC) | Global modeling of very-short-lived halogens and the role of Asian Summer Monsoon |
| June 22 | Manish Naja (Aryabhatta Research Institute, India) | Contribution of different sources over a mountain site (Nainital) in the central Himalaya |
| July 11 | Ling Zou (FZ Jülich) | Reanalysis Tropopause Data Repository and the Variability of the Tropical Tropopause from 1980 to 2021 |
| July 18 | Andrea Gordon and Emily Tinney (U Oklahoma) |
Gordon: Examination of Cross-Tropopause Transport from DCOTSS In-situ Observations of Active Overshooting Convection Tinney: Climatology, Sources, and Transport Characteristics of Observed Water Vapor Extrema in the Lower Stratosphere |
| July 25 | Marta Abalos (Universidad Complutense de Madrid, Spain) | Seasonality of future trends in lower stratospheric wave drag |
| Sep 26 | Joowan Kim (Kongju National University, Korea) | Relationship between TTL ozone and stratospheric water vapor: Insight from CCMI models |
| Oct 17 | Colin Gurganus (NOAA CSL) | Insights into Carbonyl Sulfide (OCS) Distribution and Sources in the Asian Summer Monsoon (ASM) Region: Evidence from Elevated Levels Observed in the UTLS during the ACCLIP Campaign |
| Oct 24 | Yunqian Zhu (CIRES / NOAA CSL) | Evaluating the importance of nitrate aerosol in the upper troposphere and lower stratosphere during the Asian summer monsoon season |
| Oct 31 | Joowan Kim (Kongju National University, Korea) | Ozonesonde Measurements during the ACCLIP Campaign and Their Applications |
| Nov 14 | Eleanor Waxman (NOAA CSL) | Ozone tendencies in the UTLS during ACCLIP |
| Dec 5 | Alexandre Baron (CIRES / NOAA CSL) | The Uncommon Optical and Microphysical Properties of the Hunga-Tonga Aerosol |
| Dec 12 | n/a | No Meeting - AGU |
| 2021 | ||
| Jan 19 | Bill Randel (NCAR/ACOM) | Discussion of Vortex Behavior in the ASMA (Siu and Bowman 2020 & Rupp and Haynes 2021) |
| Jan 26 | Xinyue Wang (NCAR/ACOM) | The Dynamics of Eastward Eddy Shedding from the ASMA |
| Feb 2 | Eric Ray (NOAA/CSL) | Age spectra from SEAC4RS trace gas measurements |
| Feb 9 | Victoria Treadaway (U. Miami) | Discussion of Ozone-Depleting Substances in the ASMA UTLS (Adcock et al 2020) (PDF slides) |
| Feb 16 | Qing Liang (NASA GSFC) | The Impact of the Asian Summer Monsoon and Typhoons on the UT/LS Chemical Composition |
| Feb 23 | Ren Smith (NCAR/ACOM) | Discussion of Confinement and Transport of Air in the ASMA (Legras and Bucci 2020) (PDF slides) |
| Mar 2 | Paul Newman (NASA GSFC) | O3 and H2O relationship based diagnostic of stratosphere-troposphere-transition layer |
| Mar 16 | Troy Thornberry (NOAA/ESRL) | Discussion of observed new particle formation in the ASMA UTLS (Weigel et al 2020) (PDF slides) |
| Mar 30 | Christina Williamson (NOAA/CSL) | The ATAL within the 2017 ASMA derived from airborne observations (Mahnke et al 2021) (PDF slides) |
| April 13 | Nick Davis (NCAR/ACOM) | Specified dynamics scheme impacts on wave-mean flow dynamics, convection, and tracer transport in CESM2 (WACCM6) |
| April 20 | Yutian Wu (Columbia) | Fast transport pathways into the Northern Hemisphere UTLS during northern summer (Wu et al., 2020) |
| April 27 | Mian Chin (NASA GSFC) | Understanding the aerosol composition in ATAL with integrated modeling and observations from field campaigns (PPT slides) |
| May 4 | Laura Pan (NCAR) | Asian Monsoon Transport group discussion |
| May 18 | Holger Vömel (NCAR/EOL) | Revisiting ozone sonde measurements: Uncertainties and challenges for the upper troposphere and lower stratosphere (PDF slides) |
| June 29 | Sofia Chelpon (CUNY) and Ren Smith (NCAR/ACOM) | Characterization and Evaluation of Convective Transport Time Scales over the Tropical Western Pacific (PDF slides) |
| 2019 | ||
| Feb 27 | Dina Khordakova (Juelich) | MOSES: Modular observation solutions for earth systems - a facility for the investigation of extreme weather events |
| Mar 14 | Richard Newton | Tropospheric temperature inversions in the Indian Monsoon - A climatology from GPS radio occultation measurements from 2001 to 2018 |
| Apr 12 | Xun Wang (TAMU) | Impact of convectively lofted ice on the seasonal cycle of tropical lower stratospheric water vapor |
| Jun 19 | Aurelien Podglajen (Juelich) | Retrieving the age of air spectrum from tracers |
| Jul 25 |
Eric Jensen
|
Using in situ measurements to evaluate the Lagrangian dry point approach for calculating the stratospheric-entry water vapor concentration |
| Aug 14 |
Xinyue Wang
|
Fast transport into the lower stratosphere-upper troposphere over North America during northern summer |
| Sept 25 |
Wandi Yu
|
Influence of convection on stratospheric water vapor in the North American monsoon |
| 2018 | ||
| Jan 24 | Shawn Honomichl | A Transport Pathway for Polluted Air from the Asian Summer Monsoon Anticyclone to the Global UTLS |
| Jan 31 | Eric Ray (NOAA) | The unexpected recent changes in the decline of CFC-11: New emissions, stratospheric loss variability or both? |
| Feb 14 | Daniele Visioni (Universita' dell'Aquila, Italy) | Chemical and dynamical side effects of stratospheric sulfate geoengineering: changes in upper tropospheric ice |
| Feb 28 | Bill Randel | Mainz UTLS workshop highlights summary |
| April 11 | Sasha Madronich | "Volatile chemical products emerging as largest petrochemical source of urban organic emissions” by McDonald et al. http://science.sciencemag.org.cuucar.colorado.edu/content/359/6377/760 |
| April 27 | Mingmin Zou (CAS/RADI) | Greenhouse Gas Research Planned in Chinese Earth Observing Satellite GaoFen-5 Program |
| May 9 | Joan Alexander (NWRA),Sean Davis (NOAA), and Lars Kalnajs (LASP) | Stratéole-2: Tropical UTLS Measurements from Long Duration Superpressure Balloons |
| June 6 | Bill Randel | Discussion of a new paper |
| June 20 | Martina Kraemer (Juelich) | The Asian Monsoon airborne field campaign StratoClim 2017 and observations of ice cloud properties |
| July 10 | Joowan Kim (Kongju National University, Korea) | The Madden-Julian Oscillation’s influences on Stratospheric Moisture |
| July 18 | Yutian Wu (Columbia) |
What is the transport pathway into the UTLS during northern summer?
|
| July 24 | Johnny Luo (CCNY) | On the Use of Chemical Tracers to Diagnose Convective Transport Transit Time Spectrum over the Tropical Western Pacific |
| Aug 1 | Daniel Phoenix (OU) | Impacts of Tropopause-Penetrating Convection on the Chemical Composition of the Upper Troposphere and Lower Stratosphere |
| Aug 7 | Cameron Homeyer (OU) | A 10-year Ground-based Radar Climatology of Convective Penetration of Stratospheric Intrusions and Associated Large-Scale Transport over the CONUS |
|
Aug 17 (Friday) |
Marta Abalos (Universidad Complutense de Madrid, Spain) | Impact of ozone depleting substances on the stratospheric Brewer-Dobson circulation (3:30 pm as ACOM seminar) |
| Nov 6 (Tuesday) | Bill Randel And Mijeong Park |
Beginning look at the new SAGE III data
|
| Nov 21 | Happy Thanksgiving | |
|
Nov 29 (Thursday) |
Sabine Robrecht (Juelich, Germany) | Might stratospheric ozone loss occur in mid-latitude summer today or in a future with or without geoengineering? |
| Dec 4 (Tuesday) | Kimberlee Dube (Univ. of Saskatchewan, Canada) | Stratospheric NO2 measurements from SAGE and OSIRIS |
| 2017 | ||
| Jan 18 | Laura Pan | Asian summer monsoon Chemistry Climate Impact Project (ACCLIP) |
| Jan 25 | Peter Hitchcock | Some dynamical insights on the recent disruption of the QBO from an idealized model |
| Feb 15 | Mengchu Tao | A Lagrangian model diagnosis of stratospheric contributions to the tropical middle tropospheric air |
| Mar 2 | Marta Abalos | Using e90 to study UTLS tracer transport in WACCM |
| Mar15 | Steve Massie | Observational Evidence of 3D Cloud Effects in Orbiting Carbon Observatory Measurements of CO2 |
| Apr 12 | Chengji Liu (CSU) | Synoptic formation of double tropopauses |
| July 11 | Chuntao Liu (TAMUCC) |
Properties of different types of precipitation systems revealed by the Global Precipitation Mission observations
|
| July 25 | Laura Pan | Lapse rate vs coldpoint: A tale of two tropical tropopause definitions told by tracers |
| Aug 4 | Valeria Donets (U Miani) | Shear line facilitated transport of reactive trace gases from East Asia into the deep tropics |
| Aug 7 | Gretchen Mullendore (UND) (cancelled) |
Defining the tropopause in studies of deep convection |
| Aug 16 | Rainer Volkamer (CU) | BrO and Bry profiles over the Western Pacific: Relevance of Inorganic Bromine Sources and a Bry Minimum in the Aged Tropical Tropopause Layer |
| Aug 18 | Javier Garcia-Serrano (Barcelona Supercomputing Center) | On the Hemispheric Scale of the Winter North Atlantic Oscillation |
| Aug 24 | Olga Tweedy (JHU) | Does ENSO influence summer-time ozone in the tropical lower-stratosphere? |
| Aug. 30 | John Albers (NOAA) | Trends in the Seasonality of the Brewer-Dobson Circulation Due to Radiative-Dynamical Feedbacks |
| Sep 19 |
George Kiladis (NOAA) (Cancelled) |
Variability of Stratospheric mixed Rossby-gravity, Kelvin, and external Rossby modes and connections with the troposphere |
| Sep 20 (2:30 pm) | Liz Moyer (U Chicago) | Early results from the StratoClim campaign over the Asian monsoon |
| Sep 27 | Laura Pan | Space-Time Variability of UTLS Chemical Distribution in the Asian Summer Monsoon Viewed by Limb and Nadir Satellite Sensors |
| Oct 11 | Open | |
| 2016 | ||
| Jan 6 | Bill Randel | Vernier, J. -P. .JGR 2015 http://onlinelibrary.wiley.com/doi/10.1002/2014JD022372/epdf |
| Jan 20 | Thomas Birner | Characteristics of lower stratospheric transport as inferred from age of air spectra |
| Feb 3 | Eric jensen | Processes Controlling the Distribution of Relative Humidity in the Tropical Tropopause Layer |
| Feb 17 | Laura Pan | Discussion of an Asian monsoon dynamics paper: Liu YM, Hoskins BJ, Blackburn M (2007) Impact of Tibetan orography and heating on the summer flow over Asia. J Meteorol Soc Jpn (Special 125th Anniversary Issue, Invited Review Articles) 85B:1–19 |
| Feb 25 | Jasna Pittman (NWRA) | Input into the Stratosphere As Revealed by ATTREX Observations of Greenhouse Gases |
| March 2 | Jeremiah Sjorberg (NOAA) | Stratosphere-troposphere coupling insights from both a Kelvin wave momentum flux dataset and the Sudden Stratospheric Warming Compendium |
| March 16 | Matthias Nuetzel (DLR) | Connection of (lower level) monsoon with climate indices - possible pathways to explore the UTLS response on interannual time scales |
| March 30 | Aurelien Podglajen (LMD) | Lagrangian temperature and vertical velocity fluctuations due to gravity waves in the lower stratosphere |
| April 12 | Qiang Fu (U Washington) | Tropical lower-stratospheric H2O & tropical tropopause layer cirrus: A COSMIC perspective |
| April 27 | Laura Pan | Prather et al. : An atmospheric chemist in search of the tropopause, JGR 2011: http://onlinelibrary.wiley.com/doi/10.1029/2010JD014939/epdf |
| May 11 | Chuck Bardeen | Initial evaluation of UTLS temperature, water vapor and clouds in CESM6 |
| June 16 | Cameron Homeyer (OU) | Procuring a Toolbox for Studying Tropopause-Penetrating Convection : Methods, Observations, and Models |
| July 13 | Bill Randel | Relationships between outgoing longwave radiation and diabatic heating in reanalyses |
| July 20 | Minghui Diao (SJSU) | Comparisons of ice supersaturation and ice microphysical properties between in-situ observations and a hierarchy of models: a cloud-resolving model, WRF and CAM5 |
| Agust 23 | Johnny Luo (CCNY) | Satellite-Based Estimation of Convective and Large-Scale Mass Fluxes and Implications for Convective Transport of Composition |
| August 25 | Lorenzo Polvani (Columbia) | The impact of ozone depleting substances on tropical upwelling, as revealed by the absence of lower stratospheric cooling since the late 1990s |
| Sept. 14 | Bernd Kaercher (DLR) | Homogeneous Ice Formation in Supercooled Water Clouds |
| Sept. 28 | Chengjun Yang (STU, China) | The signal of the Madden-Julian Oscillation in Southern middle atmosphere during austral winter |
| Oct 12 | John Bergman | The viability of trajectory analysis for diagnosing dynamical and chemical influences on ozone concentrations in the tropical UTLS: Lessons learned in complex systems analysis |
| Oct 26 | Marta Abalos | Phase-speed spectra of eddy tracer fluxes linked to isentropic stirring and mixing in the upper troposphere and lower stratosphere |
| Nov 9 | Eric Jensen | An overview of the POSIDON WB-57 campaing in Guam |
| 2015 | ||
| July 17 | Daniel Gilford (MIT) | Nonlocal radiative effects of abrupt drops in tropical tropopause layer water vapor and ozone |
| July 24 | Aditi Sheshadri (MIT) | Variability of the polar stratospheric vortex and its impact on surface climate patterns in an idealized AGCM |
| Aug 5 | Claudia Stephan (CU) | Gravity Waves Generated by Convection: A New Idealized Model Tool and Direct Validation with Satellite Observations |
| Sept 2 | Ken Minschwaner (NM Tech) | The hunt for laminae in UTLS ozonesonde measurements: What can they tell us about transport and dynamics? |
| Sept 16 | Mijeong Park and Bill Randel | Variability of reactive nitrogen species linked to the stratospheric QBO |
| Sept 30 | Marta Abalos | Interannual variability of effective diffusivity in the UTLS |
| Oct 14 | Joowan Kim | Large-scale temperature and moisture responses to deep convection in the tropical UTLS: observations from COSMIC GPS RO and Aura MLS |
| Oct 28 | Thomas Birner (CSU) | The discovery of the stratosphere |
| Nov 5 | Rafael Fernandez (CONICET/FCEN-UNCuyo) |
Global Distributions of Very Short-Lived Halogens: from the Ocean Surface to the Tropical Tropopause Layer |
| Nov 17 | Peter Hitchcock (U. Cambridge) |
A radiative origin for the double-peak structure of upwelling in the tropical lower stratosphere |
ACOM Type
UTLS Research