Search Results - "Oltmans, Samuel J"

Climate variability modulates western US ozone air quality in spring via deep stratospheric intrusions by Lin, Meiyun, Fiore, Arlene M., Horowitz, Larry W., Langford, Andrew O., Oltmans, Samuel J., Tarasick, David, Rieder, Harald E.

“…Evidence suggests deep stratospheric intrusions can elevate western US surface ozone to unhealthy levels during spring. These intrusions can be classified as…”
Get full text

Springtime high surface ozone events over the western United States: Quantifying the role of stratospheric intrusions by Lin, Meiyun, Fiore, Arlene M., Cooper, Owen R., Horowitz, Larry W., Langford, Andrew O., Levy II, Hiram, Johnson, Bryan J., Naik, Vaishali, Oltmans, Samuel J., Senff, Christoph J.

“…The published literature debates the extent to which naturally occurring stratospheric ozone intrusions reach the surface and contribute to exceedances of the…”
Get full text

Estimates of background surface ozone concentrations in the United States based on model-derived source apportionment by Lefohn, Allen S., Emery, Christopher, Shadwick, Douglas, Wernli, Heini, Jung, Jeagun, Oltmans, Samuel J.

“…We analyze background surface ozone (O3) concentrations as estimated by coupled GEOS-Chem/CAMx models for 23 monitoring sites across the US at high- and…”
Get full text

Stratospheric water vapor trends over Boulder, Colorado: Analysis of the 30 year Boulder record by Hurst, Dale F., Oltmans, Samuel J., Vömel, Holger, Rosenlof, Karen H., Davis, Sean M., Ray, Eric A., Hall, Emrys G., Jordan, Allen F.

“…Trend analyses are presented for 30 years (1980–2010) of balloon‐borne stratospheric water vapor measurements over Boulder, Colorado. The data record is broken…”
Get full text

Tropospheric Ozone Assessment Report: Tropospheric Ozone From 1877 to 2016, Observed Levels, Trends and Uncertainties by Galbally, Ian E., Cooper, Owen R., Schultz, Martin G., Ancellet, Gerard, Leblanc, Thierry, Wallington, Timothy J., Ziemke, Jerry, Liu, Xiong, Steinbacher, Martin, Staehelin, Johannes, Vigouroux, Corinne, Hannigan, James W., García, Omaira, Foret, Gilles, Zanis, Prodromos, Weatherhead, Elizabeth, Petropavlovskikh, Irina, Worden, Helen, Osman, Mohammed, Liu, Jane, Chang, Kai-Lan, Gaudel, Audrey, Lin, Meiyun, Granados-Muñoz, Maria, Thompson, Anne M, Oltmans, Samuel J., Cuesta, Juan, Dufour, Gaelle, Thouret, Valerie, Hassler, Birgit, Trickl, Thomas, Neu, Jessica L

“…From the earliest observations of ozone in the lower atmosphere in the 19th century, both measurement methods and the portion of the globe observed have…”
Get full text

Characterizing changes in surface ozone levels in metropolitan and rural areas in the United States for 1980–2008 and 1994–2008 by Lefohn, Allen S., Shadwick, Douglas, Oltmans, Samuel J.

“…In this analysis, we characterize urban and rural ozone (O 3) trends across the US for the periods 1980–2008 (29 years) and 1994–2008 (15 years) using three…”
Get full text

Quantifying the importance of stratospheric-tropospheric transport on surface ozone concentrations at high- and low-elevation monitoring sites in the United States by Lefohn, Allen S., Wernli, Heini, Shadwick, Douglas, Oltmans, Samuel J., Shapiro, Melvyn

“…In this study, we quantify the frequency of stratosphere-troposphere exchange (STE) events that result in ozone (O3) concentration enhancements (i.e., hourly…”
Get full text

The importance of stratospheric–tropospheric transport in affecting surface ozone concentrations in the western and northern tier of the United States by Lefohn, Allen S., Wernli, Heini, Shadwick, Douglas, Limbach, Sebastian, Oltmans, Samuel J., Shapiro, Melvyn

“…Stratospheric–tropospheric exchange (STE) processes contribute at both high and low-elevation monitoring sites to background ozone (O 3) concentrations. This…”
Get full text

Springtime boundary layer ozone depletion at Barrow, Alaska: Meteorological influence, year-to-year variation, and long-term change by Oltmans, Samuel J., Johnson, Bryan J., Harris, Joyce M.

“…In April 2008 and March–April 2009 near daily ozonesonde measurements were made over a several week period to study springtime Arctic boundary layer ozone loss…”
Get full text

Assessment of the performance of ECC-ozonesondes under quasi-flight conditions in the environmental simulation chamber: Insights from the Juelich Ozone Sonde Intercomparison Experiment (JOSIE) by Smit, Herman G. J., Straeter, Wolfgang, Johnson, Bryan J., Oltmans, Samuel J., Davies, Jonathan, Tarasick, David W., Hoegger, Bruno, Stubi, Rene, Schmidlin, F. J., Northam, T., Thompson, Anne M., Witte, Jacquelyn C., Boyd, Ian, Posny, Françoise

“…Since 1996, quality assurance experiments of electrochemical concentration cell (ECC) ozonesondes of two different model types (SPC‐6A and ENSCI‐Z) have been…”
Get full text

Rapid photochemical production of ozone at high concentrations in a rural site during winter by Schnell, Russell C, Oltmans, Samuel J, Neely, Ryan R, Endres, Maggie S, Molenar, John V, White, Allen B

“…Ozone is an air pollutant that can cause severe respiratory health effects. Photochemical ozone production near the Earth's surface is considered a summertime,…”
Get full text

Summertime surface O3 behavior and deposition to tundra in the Alaskan Arctic by Van Dam, Brie, Helmig, Detlev, Doskey, Paul V., Oltmans, Samuel J.

“…Atmospheric turbulence quantities, boundary layer ozone (O3) levels, and O3 deposition to the tundra surface were investigated at Toolik Lake, AK, during the…”
Get full text

Validation of Aura Microwave Limb Sounder stratospheric water vapor measurements by the NOAA frost point hygrometer by Hurst, Dale F., Lambert, Alyn, Read, William G., Davis, Sean M., Rosenlof, Karen H., Hall, Emrys G., Jordan, Allen F., Oltmans, Samuel J.

“…Differences between stratospheric water vapor measurements by NOAA frost point hygrometers (FPHs) and the Aura Microwave Limb Sounder (MLS) are evaluated for…”
Get full text

Improving ECC Ozonesonde Data Quality: Assessment of Current Methods and Outstanding Issues by Tarasick, David W., Smit, Herman G. J., Thompson, Anne M., Morris, Gary A., Witte, Jacquelyn C., Davies, Jonathan, Nakano, Tatsumi, Van Malderen, Roeland, Stauffer, Ryan M., Johnson, Bryan J., Stübi, Rene, Oltmans, Samuel J., Vömel, Holger

“…We review the current state of knowledge of ozonesonde uncertainty and bias, with reference to recent developments in laboratory and field experiments. In the…”
Get full text

Validation of Tropospheric Emission Spectrometer (TES) nadir ozone profiles using ozonesonde measurements by Nassar, Ray, Logan, Jennifer A., Worden, Helen M., Megretskaia, Inna A., Bowman, Kevin W., Osterman, Gregory B., Thompson, Anne M., Tarasick, David W., Austin, Shermane, Claude, Hans, Dubey, Manvendra K., Hocking, Wayne K., Johnson, Bryan J., Joseph, Everette, Merrill, John, Morris, Gary A., Newchurch, Mike, Oltmans, Samuel J., Posny, Françoise, Schmidlin, F. J., Vömel, Holger, Whiteman, David N., Witte, Jacquelyn C.

“…We compare Tropospheric Emission Spectrometer (TES) version 2 (V002) nadir ozone profiles with ozonesonde profiles from the Intercontinental Chemical Transport…”
Get full text

Strategic ozone sounding networks: Review of design and accomplishments by Thompson, Anne M., Oltmans, Samuel J., Tarasick, David. W., von der Gathen, Peter, Smit, Herman G.J., Witte, Jacquelyn C.

“…Ozone soundings are used to integrate models, satellite, aircraft and ground-based measurements for better interpretation of ozone variability, including…”
Get full text

A review of surface ozone in the polar regions by Helmig, Detlev, Oltmans, Samuel J., Carlson, Daniel, Lamarque, Jean-Francois, Jones, Anna, Labuschagne, Casper, Anlauf, Kurt, Hayden, Katherine

“…Surface ozone records from ten polar research stations were investigated for the dependencies of ozone on radiative processes, snow-photochemisty, and synoptic…”
Get full text

Atmospheric comparison of electrochemical cell ozonesondes from different manufacturers, and with different cathode solution strengths: The Balloon Experiment on Standards for Ozonesondes by Deshler, Terry, Mercer, Jennifer L., Smit, Herman G. J., Stubi, Rene, Levrat, Gilbert, Johnson, Bryan J., Oltmans, Samuel J., Kivi, Rigel, Thompson, Anne M., Witte, Jacquelyn, Davies, Jonathan, Schmidlin, F. J., Brothers, G., Sasaki, Toru

“…A balloon flight to compare 18 ozonesondes with an ozone photometer and with ozone column measurements from Dobson and Brewer spectrophotometers was completed…”
Get full text

Southern Hemisphere Additional Ozonesondes (SHADOZ) 1998–2004 tropical ozone climatology: 3. Instrumentation, station-to-station variability, and evaluation with simulated flight profiles by Thompson, Anne M., Witte, Jacquelyn C., Smit, Herman G. J., Oltmans, Samuel J., Johnson, Bryan J., Kirchhoff, Volker W. J. H., Schmidlin, F. J.

“…The Southern Hemisphere Additional Ozonesondes (SHADOZ) project has collected more than 3000 ozone profiles from 14 tropical and subtropical sites using…”
Get full text

Alaskan and Canadian forest fires exacerbate ozone pollution over Houston, Texas, on 19 and 20 July 2004 by Morris, Gary A., Hersey, Scott, Thompson, Anne M., Pawson, Steven, Nielsen, J. Eric, Colarco, Peter R., McMillan, W. Wallace, Stohl, Andreas, Turquety, Solene, Warner, Juying, Johnson, Bryan J., Kucsera, Tom L., Larko, David E., Oltmans, Samuel J., Witte, Jacquelyn C.

“…On Monday, 19 July, and Tuesday, 20 July 2004, the air over Houston, Texas, appeared abnormally hazy. Transport model results and data from the Atmospheric…”
Get full text