Drummond, James R.
Permanent URI for this collectionhttps://hdl.handle.net/10222/22061
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Item Open Access Testing the Validity of the Optical Diffusion-Coefficient - Line-Shape Measurements of Co Perturbed by N2(1993-09) DUGGAN, P.; SINCLAIR, PM; LEFLOHIC, MP; FORSMAN, JW; BERMAN, R.; MAY, AD; DRUMMOND, JRNo abstract available.Item Open Access A Pressure Modulator Radiometer for Measuring Stratospheric Trace Gases(1989-11) DRUMMOND, JR; TURNER, D.; ASHTON, A.No abstract available.Item Open Access Dicke narrowing as an example of line mixing(1999-05) Dolbeau, S.; Berman, R.; Drummond, JR; May, ADNo abstract available.Item Open Access Infrared water vapor continuum absorption at atmospheric temperatures(American Institute of Physics Inc, 2005) Cormier, John G.; Hodges, Joseph T.; Drummond, James R.We have used a continuous-wave carbon dioxide laser in a single-mode realization of cavity ring-down spectroscopy to measure absorption coefficients of water vapor at 944 cm-1 for several temperatures in the range 270-315 K. The conventional description of water vapor infrared absorption is applied, in which the absorption is modeled in two parts consisting of local line absorption and the remaining residual absorption, which has become known as the water vapor continuum. This water vapor continuum consists of distinct water-water, water-nitrogen, and water-oxygen continua. The water-water continuum absorption coefficient is found to have a magnitude of Cs (296 K) = (1.820.02) 10-22 cm2 molecule-1 atm-1, and the water-nitrogen coefficient has a magnitude of Cn (296 K) = (7.30.4) 10-25 cm2 molecule-1 atm-1. The temperature dependences of both the water-water and the water-nitrogen continua are shown to be well represented by a model describing the expected behavior of weakly bound binary complexes. Using this model, our data yield dissociation energies of De = (-15.90.3) kJmole for the water dimer and De = (-3.21.7) kJmole for the water-nitrogen complex. These values are in excellent agreement with recent theoretical predictions of De =-15.7 kJmole (water dimer) and De =-2.9 kJmole (water-nitrogen complex), as well as the experimentally determined value of De = (-15.32.1) kJmole for the water dimer obtained by investigators employing a thermal conductivity technique. Although there is reasonably good agreement with the magnitude of the continuum absorption coefficients, the agreement on temperature dependence is less satisfactory. While our results are suggestive of the role played by water dimers and water complexes in producing the infrared continuum, the uncertain spectroscopy of the water dimer in this spectral region prevents us from making a firm conclusion. In the meantime, empirical models of water vapor continuum absorption, essential for atmospheric radiative transfer calculations, should be refined to give better agreement with our low-uncertainty continuum absorption data. 2005 American Institute of Physics.Item Open Access Cavity ringdown spectroscopy measurements of the infrared water vapor continuum(American Institute of Physics Inc, 2002) Cormier, John G.; Ciurylo, Roman; Drummond, James R.The measurements of the water vapor continuum were analyzed using infrared cavity ringdown spectroscopy (CRDS) at frequencies of 931.002, 944.195 and 969.104 cm-1. The experiments uses a continuous-wave CO2 laser and an acousto-optic modulator to create laser pulses which are injected into a 100 cm long near-confocal ringdown cavity. It is found that the far wings of water vapor lines are the primary agent responsible for the water vapor continuum.Item Open Access The spring 2011 final stratospheric warming above Eureka: anomalous dynamics and chemistry(2013) Adams, C.; Strong, K.; Zhao, X.; Bourassa, A. E.; Daffer, W. H.; Degenstein, D.; Drummond, J. R.; Farahani, E. E.; Fraser, A.; Lloyd, N. D.; Manney, G. L.; McLinden, C. A.; Rex, M.; Roth, C.; Strahan, S. E.; Walker, K. A.; Wohltmann, I.No abstract available.Item Open Access Decadal record of satellite carbon monoxide observations(2013) Worden, H. M.; Deeter, M. N.; Frankenberg, C.; George, M.; Nichitiu, F.; Worden, J.; Aben, I.; Bowman, K. W.; Clerbaux, C.; Coheur, P. F.; de Laat, A. T. J.; Detweiler, R.; Drummond, J. R.; Edwards, D. P.; Gille, J. C.; Hurtmans, D.; Luo, M.; Martinez-Alonso, S.; Massie, S.; Pfister, G.; Warner, J. X.No abstract available.Item Open Access On the application of cavity ringdown spectroscopy to measurements of line shapes and continuum absorption(2002) Cormier, JG; Hodges, JT; Drummond, JR; Back, CANo abstract available.Item Open Access Vertical and interhemispheric links in the stratosphere-mesosphere as revealed by the day-to-day variability of Aura-MLS temperature data(2009) Xu, X.; Manson, A. H.; Meek, C. E.; Chshyolkova, T.; Drummond, J. R.; Hall, C. M.; Riggin, D. M.; Hibbins, R. E.No abstract available.Item Open Access Simultaneous ground-based observations of O3, HCl, N2O, and CH4 over Toronto, Canada by three Fourier transform spectrometers with different resolutions(2007-02) Wunch, D.; Taylor, J. R.; Fu, D.; Bernath, P.; Drummond, J. R.; Midwinter, C.; Strong, K.; Walker, K. A.No abstract available.Item Open Access University of Toronto's balloon-borne fourier transform spectrometer(2006-09) Wunch, Debra; Midwinter, Clive; Drummond, James R.; McElroy, C. Thomas; Bages, Anne-FloreNo abstract available.Item Open Access Relationship between variability of the semidiurnal tide in the Northern Hemisphere mesosphere and quasi-stationary planetary waves throughout the global middle atmosphere(2009) Xu, X.; Manson, A. H.; Meek, C. E.; Chshyolkova, T.; Drummond, J. R.; Hall, C. M.; Jacobi, Ch; Riggin, D.; Hibbins, R. E.; Tsutsumi, M.; Hocking, W. K.; Ward, W. E.No abstract available.Item Open Access Increased Northern Hemispheric carbon monoxide burden in the troposphere in 2002 and 2003 detected from the ground and from space(2005-02) Yurganov, LN; Duchatelet, P.; Dzhola, AV; Edwards, DP; Hase, F.; Kramer, I.; Mahieu, E.; Mellqvist, J.; Notholt, J.; Novelli, PC; Rockmann, A.; Scheel, HE; Schneider, M.; Schulz, A.; Strandberg, A.; Sussmann, R.; Tanimoto, H.; Velazco, V.; Drummond, JR; Gille, JCNo abstract available.Item Open Access Infrared water vapor continuum absorption at atmospheric temperatures(2005-03) Cormier, JG; Hodges, JT; Drummond, JRNo abstract available.Item Open Access Solving the line-shape problem with speed-dependent broadening and shifting and with Dicke narrowing. II. Application(2002-01) Ciurylo, R.; Shapiro, DA; Drummond, JR; May, ADNo abstract available.Item Open Access Comparison of an ab initio calculation of the CO-Ar P(2) line shape with high-resolution measurements(2002) Wehr, R.; Vitcu, A.; Ciurylo, R.; Thibault, F.; Drummond, JR; May, AD; Back, CANo abstract available.Item Open Access High-resolution studies on the influence of velocity-changing collisions on atomic and molecular line shapes.(2002) Ciurylo, R.; Bielski, A.; Drummond, JR; Lisak, D.; May, AD; Pine, AS; Shapiro, DA; Szudy, J.; Trawinski, RS; Back, CANo abstract available.Item Open Access Dicke-narrowed line shapes in CO-Ar: Measurements, calculations, and a revised interpretation(2006) Wehr, R.; Ciurylo, R.; Vitcu, A.; Thibault, F.; Shapiro, D. A.; Liu, W. -K; McCourt, F. R. W.; Drummond, J. R.; May, A. D.; Oks, E. Pindzola,M.No abstract available.Item Open Access Spectral line shape of the P(2) transition in CO-Ar: Uncorrelated ab initio calculation(2002-12) Wehr, R.; Vitcu, A.; Ciurylo, R.; Thibault, F.; Drummond, JR; May, ADNo abstract available.Item Open Access High Resolution and High Signal‐to‐Noise Measurements in the 0310 ← 0110 Q‐Branch of N2O at 1160 cm−1(2002) Vitcu, A.; Wehr, R.; Ciurylo, R.; Drummond, JR; May, AD; Back, CANo abstract available.
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