Search Results - "Sayres, D S"

Observations of deep convective influence on stratospheric water vapor and its isotopic composition by Hanisco, Thomas F., Moyer, E. J., Weinstock, E. M., St. Clair, J. M., Sayres, D. S., Smith, J. B., Lockwood, R., Anderson, J. G., Dessler, A. E., Keutsch, F. N., Spackman, J. R., Read, W. G., Bui, T. P.

“…In situ observations of H2O and HDO in the midlatitude stratosphere are used to evaluate the role of convection in determining the stratospheric water budget…”
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Design considerations in high-sensitivity off-axis integrated cavity output spectroscopy by Moyer, E.J., Sayres, D.S., Engel, G.S., St. Clair, J.M., Keutsch, F.N., Allen, N.T., Kroll, J.H., Anderson, J.G.

“…Off-axis integrated cavity output spectroscopy (OA-ICOS) has generated much interest because it potentially allows highly sensitive field measurements with…”
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Influence of convection on the water isotopic composition of the tropical tropopause layer and tropical stratosphere by Sayres, D. S., Pfister, L., Hanisco, T. F., Moyer, E. J., Smith, J. B., St. Clair, J. M., O'Brien, A. S., Witinski, M. F., Legg, M., Anderson, J. G.

“…We present the first in situ measurements of HDO across the tropical tropopause, obtained by the integrated cavity output spectroscopy (ICOS) and Hoxotope…”
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Ice supersaturations exceeding 100% at the cold tropical tropopause: implications for cirrus formation and dehydration by Jensen, E. J., Smith, J. B., Pfister, L., Pittman, J. V., Weinstock, E. M., Sayres, D. S., Herman, R. L., Troy, R. F., Rosenlof, K., Thompson, T. L., Fridlind, A. M., Hudson, P. K., Cziczo, D. J., Heymsfield, A. J., Schmitt, C., Wilson, J. C.

“…Recent in situ measurements at tropical tropopause temperatures as low as 187 K indicate supersaturations with respect to ice exceeding 100% with little or no…”
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Formation of large (≃100 μm) ice crystals near the tropical tropopause by Jensen, E. J., Pfister, L., Bui, T. V., Lawson, P., Baker, B., Mo, Q., Baumgardner, D., Weinstock, E. M., Smith, J. B., Moyer, E. J., Hanisco, T. F., Sayres, D. S., Clair, J. M. St, Alexander, M. J., Toon, O. B., Smith, J. A.

“…Recent high-altitude aircraft measurements with in situ imaging instruments indicated the presence of relatively large (≃100 μm length), thin (aspect ratios of…”
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Nitric acid uptake on subtropical cirrus cloud particles by Popp, P. J., Gao, R. S., Marcy, T. P., Fahey, D. W., Hudson, P. K., Thompson, T. L., Kärcher, B., Ridley, B. A., Weinheimer, A. J., Knapp, D. J., Montzka, D. D., Baumgardner, D., Garrett, T. J., Weinstock, E. M., Smith, J. B., Sayres, D. S., Pittman, J. V., Dhaniyala, S., Bui, T. P., Mahoney, M. J.

“…The redistribution of HNO3 via uptake and sedimentation by cirrus cloud particles is considered an important term in the upper tropospheric budget of reactive…”
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Quantifying the impact of the North American monsoon and deep midlatitude convection on the subtropical lowermost stratosphere using in situ measurements by Weinstock, E. M., Pittman, J. V., Sayres, D. S., Smith, J. B., Anderson, J. G., Wofsy, S. C., Xueref, I., Gerbig, C., Daube, B. C., Pfister, L., Richard, E. C., Ridley, B. A., Weinheimer, A. J., Jost, H.-J., Lopez, J. P., Loewenstein, M., Thompson, T. L.

“…The chemical composition of the lowermost stratosphere exhibits both spatial and temporal variability depending upon the relative strength of (1) isentropic…”
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Validation and determination of ice water content-radar reflectivity relationships during CRYSTAL-FACE: Flight requirements for future comparisons by Sayres, D. S., Smith, J. B., Pittman, J. V., Weinstock, E. M., Anderson, J. G., Heymsfield, G., Li, L., Fridlind, A. M., Ackerman, A. S.

“…In situ measurements of cirrus ice water content (IWC) by the Harvard water vapor and total water instruments during Cirrus Regional Study of Tropical Anvils…”
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Measurements of relative humidity in a persistent contrail by Gao, R.S., Fahey, D.W., Popp, P.J., Marcy, T.P., Herman, R.L., Weinstock, E.M., Smith, J.B., Sayres, D.S., Pittman, J.V., Rosenlof, K.H., Thompson, T.L., Bui, P.T., Baumgardner, D.G., Anderson, B.E., Kok, G., Weinheimer, A.J.

“…Persistent contrails are a common feature of the upper troposphere. We describe two methods for intercomparing and evaluating RH i measurements in a persistent…”
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Evaluation of UT/LS hygrometer accuracy by intercomparison during the NASA MACPEX mission by Rollins, A. W., Thornberry, T. D., Gao, R. S., Smith, J. B., Sayres, D. S., Sargent, M. R., Schiller, C., Krämer, M., Spelten, N., Hurst, D. F., Jordan, A. F., Hall, E. G., Vömel, H., Diskin, G. S., Podolske, J. R., Christensen, L. E., Rosenlof, K. H., Jensen, E. J., Fahey, D. W.

“…Acquiring accurate measurements of water vapor at the low mixing ratios (< 10 ppm) encountered in the upper troposphere and lower stratosphere (UT/LS) has…”
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High precision methane isotopologue ratio measurements at ambient mixing ratios using integrated cavity output spectroscopy by Witinski, M. F., Sayres, D. S., Anderson, J. G.

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Validation of the Harvard Lyman-? in situ water vapor instrument: Implications for the mechanisms that control stratospheric water vapor by Weinstock, E M, Smith, J B, Sayres, D S, Pittman, J V, Spackman, J R, Hintsa, E J, Hanisco, T F, Moyer, E J, St. Clair, J M, Sargent, M R, Anderson, J G

“…Building on previously published details of the laboratory calibrations of the Harvard Lyman- photofragment fluorescence hygrometer (HWV) on the NASA ER-2 and…”
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Validation of the Harvard Lyman-α in situ water vapor instrument: Implications for the mechanisms that control stratospheric water vapor by Weinstock, E. M., Smith, J. B., Sayres, D. S., Pittman, J. V., Spackman, J. R., Hintsa, E. J., Hanisco, T. F., Moyer, E. J., St. Clair, J. M., Sargent, M. R., Anderson, J. G.

“…Building on previously published details of the laboratory calibrations of the Harvard Lyman‐α photofragment fluorescence hygrometer (HWV) on the NASA ER‐2 and…”
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Correction to “Nitric acid uptake on subtropical cirrus cloud particles” by Popp, P. J., Gao, R. S., Marcy, T. P., Fahey, D. W., Hudson, P. K., Thompson, T. L., Kärcher, B., Ridley, B. A., Weinheimer, A. J., Knapp, D. J., Montzka, D. D., Baumgardner, D., Garrett, T. J., Weinstock, E. M., Smith, J. B., Sayres, D. S., Pittman, J. V., Dhaniyala, S., Bui, T. P., Mahoney, M. J.

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Space weather: Response of large-scale geopotentials to an interplanetary magnetic cloud by Lanzerotti, L. J., Medford, L. V., Sayres, D. S., Maclennan, C. G., Lepping, R. P., Szabo, A.

“…The interaction of solar wind disturbances with the Earth's magnetosphere can produce disturbances, and at times complete disruptions, of technological systems…”
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Permafrost nitrous oxide emissions observed on a landscape scale using the airborne eddy-covariance method by Wilkerson, Jordan, Dobosy, Ronald, Sayres, David S, Healy, Claire, Dumas, Edward, Baker, Bruce, Anderson, James G

“…The microbial by-product nitrous oxide (N2O), a potent greenhouse gas and ozone depleting substance, has conventionally been assumed to have minimal emissions…”
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Airborne observations of upper troposphere and lower stratosphere composition change in active convection producing above-anvil cirrus plumes by Gordon, Andrea E, Homeyer, Cameron R, Smith, Jessica B, Ueyama, Rei, Dean-Day, Jonathan M, Atlas, Elliot L, Smith, Kate, Pittman, Jasna V, Sayres, David S, Wilmouth, David M, Pandey, Apoorva, St. Clair, Jason M, Hanisco, Thomas F, Hare, Jennifer, Hannun, Reem A, Wofsy, Steven, Daube, Bruce C, Donnelly, Stephen

“…Tropopause-overshooting convection in the midlatitudes provides a rapid transport pathway for air from the lower troposphere to reach the upper troposphere and…”
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Arctic regional methane fluxes by ecotope as derived using eddy covariance from a low-flying aircraft by Sayres, David S, Dobosy, Ronald, Healy, Claire, Dumas, Edward, Kochendorfer, John, Munster, Jason, Wilkerson, Jordan, Baker, Bruce, Anderson, James G

“…The Arctic terrestrial and sub-sea permafrost region contains approximately 30 % of the global carbon stock, and therefore understanding Arctic methane…”
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In situ observations of stratospheric HCl using three-mirror integrated cavity output spectroscopy by Wilkerson, Jordan, Sayres, David S, Smith, Jessica B, Allen, Norton, Rivero, Marco, Greenberg, Mike, Martin, Terry, Anderson, James G

“…Stratospheric HCl observations are an important diagnostic for the evaluation of catalytic processes that impact the ozone layer. We report here in situ…”
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Response of large-scale geoelectric fields to identified interplanetary disturbances and the equatorial ring current by Lanzerotti, L.J., Sayres, D.S., Medford, L.V., Maclennan, C.G., Lepping, R.P., Szabo, A.

“…The changes in the geoelectric field G (mV/km) between Hawaii and Guam are examined during four small geomagnetic disturbances in 1995 and 1996 when…”
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