• Beasley, D., , R. R. Martin, , and D. R. Bull, 1993: An overview of genetic algorithms: Part 1. Fundamentals. Univ. Comput., 15 (2), 5869.

    • Search Google Scholar
    • Export Citation
  • Blossey, P., , Z. Kuang, , and D. M. Romps, 2010: Isotopic composition of water in the tropical tropopause layer in cloud-resolving simulations of an idealized tropical circulation. J. Geophys. Res.,115, D24309, doi:10.1029/2010JD014554.

  • Bolot, M., , B. Legras, , and E. J. Moyer, 2013: Modelling and interpreting the isotopic composition of water vapour in convective updrafts. Atmos. Chem. Phys., 13, 79037935, doi:10.5194/acp-13-7903-2013.

    • Search Google Scholar
    • Export Citation
  • Bony, S., , C. Risi, , and F. Vimeux, 2008: Influence of convective processes on the isotopic composition (δ18O and δD) of precipitation and water vapor in the tropics: 1. Radiative-convective equilibrium and Tropical Ocean–Global Atmosphere–Coupled Ocean-Atmosphere Response Experiment (TOGA-COARE) simulations. J. Geophys. Res., 113, D19305, doi:10.1029/2008JD009942.

    • Search Google Scholar
    • Export Citation
  • Brogniez, H., , and R. Roca, 2009: A study of the free tropospheric humidity interannual variability using Meteosat data and an advection–condensation transport model. J. Climate, 22, 67736787, doi:10.1175/2009JCLI2963.1.

    • Search Google Scholar
    • Export Citation
  • Cau, P., , J. Methven, , and B. Hoskins, 2007: Origins of dry air in the tropics and subtropics. J. Climate, 20, 27452759, doi:10.1175/JCLI4176.1.

    • Search Google Scholar
    • Export Citation
  • Ciais, P., , and J. Jouzel, 1994: Deuterium and oxygen-18 in precipitation: Isotopic model, including mixed cloud processes. J. Geophys. Res., 99 (D8), 16 79316 803, doi:10.1029/94JD00412.

    • Search Google Scholar
    • Export Citation
  • Colle, B. A., , and C. F. Mass, 1995: The structure and evolution of cold surges east of the Rocky Mountains. Mon. Wea. Rev., 123, 25772610, doi:10.1175/1520-0493(1995)123<2577:TSAEOC>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Couhert, A., , T. Schneider, , J. Li, , D. E. Waliser, , and A. M. Tompkins, 2010: The maintenance of the relative humidity of the subtropical free troposphere. J. Climate, 23, 390403, doi:10.1175/2009JCLI2952.1.

    • Search Google Scholar
    • Export Citation
  • Draxler, R. R., , and G. D. Hess, 1998: An overview of the HYSPLIT 4 modelling system for trajectories. Aust. Meteor. Mag., 47, 295–308.

    • Search Google Scholar
    • Export Citation
  • Ek, M. B., , K. E. Mitchell, , Y. Lin, , E. Rogers, , P. Grunmann, , V. Koren, , G. Gayno, , and J. D. Tarpley, 2003: Implementation of Noah land surface model advances in the National Centers for Environmental Prediction operational mesoscale Eta model. J. Geophys. Res., 108, 8851, doi:10.1029/2002JD003296.

    • Search Google Scholar
    • Export Citation
  • Galewsky, J., , and J. V. Hurley, 2010: An advection-condensation model for subtropical water vapor isotopic ratios. J. Geophys. Res., 115, D16116, doi:10.1029/2009JD013651.

    • Search Google Scholar
    • Export Citation
  • Galewsky, J., , and K. Samuels-Crow, 2014: Water vapor isotopic composition of a stratospheric air intrusion: Measurements from the Chajnantor Plateau, Chile. J. Geophys. Res. Atmos., 119, 96799691, doi:10.1002/2014JD022047.

    • Search Google Scholar
    • Export Citation
  • Galewsky, J., , and K. Samuels-Crow, 2015: Summertime moisture transport to the southern South American Altiplano: Constraints from in-situ measurements of water vapor isotopic composition. J. Climate, 28, 26352649, doi:10.1175/JCLI-D-14-00511.1.

    • Search Google Scholar
    • Export Citation
  • Galewsky, J., , A. Sobel, , and I. Held, 2005: Diagnosis of subtropical humidity dynamics using tracers of last saturation. J. Atmos. Sci., 62, 33533367, doi:10.1175/JAS3533.1.

    • Search Google Scholar
    • Export Citation
  • Galewsky, J., , M. Strong, , and Z. D. Sharp, 2007: Measurements of water vapor D/H ratios from Mauna Kea, Hawaii, and implications for subtropical humidity dynamics. Geophys. Res. Lett.,34, L22808, doi:10.1029/2007GL031330.

  • Galewsky, J., , C. Rella, , Z. Sharp, , K. Samuels, , and D. Ward, 2011: Surface measurements of upper tropospheric water vapor isotopic composition on the Chajnantor Plateau, Chile. Geophys. Res. Lett., 38, L17803, doi:10.1029/2011GL048557.

    • Search Google Scholar
    • Export Citation
  • Garreaud, R., 2000: Cold air incursions over subtropical South America: Mean structure and dynamics. Mon. Wea. Rev., 128, 25442559, doi:10.1175/1520-0493(2000)128<2544:CAIOSS>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Gat, J., 1996: Oxygen and hydrogen isotopes in the hydrologic cycle. Annu. Rev. Earth Planet. Sci., 24, 225262, doi:10.1146/annurev.earth.24.1.225.

    • Search Google Scholar
    • Export Citation
  • Gat, J., , B. Klein, , Y. Kushnir, , W. Roether, , H. Wernli, , R. Yam, , and A. Shemesh, 2003: Isotope composition of air moisture over the Mediterranean Sea: An index of the air–sea interaction pattern. Tellus, 55B, 953965, doi:10.1034/j.1600-0889.2003.00081.x.

    • Search Google Scholar
    • Export Citation
  • Gettelman, A., , and D. E. Kinnison, 2007: The global impact of supersaturation in a coupled chemistry-climate model. Atmos. Chem. Phys., 7, 16291643, doi:10.5194/acp-7-1629-2007.

    • Search Google Scholar
    • Export Citation
  • Giovanelli, R., , and J. Darling, 2001: The optical/infrared astronomical quality of high Atacama sites. II. Infrared characteristics. Publ. Astron. Soc. Pac., 113, 803813, doi:10.1086/322136.

    • Search Google Scholar
    • Export Citation
  • Hong, S.-Y., , Y. Noh, , and J. Dudhia, 2006: A new vertical diffusion package with an explicit treatment of entrainment processes. Mon. Wea. Rev., 134, 23182341, doi:10.1175/MWR3199.1.

    • Search Google Scholar
    • Export Citation
  • Huang, Y., , S. T. Siems, , and M. J. Manton, 2014: An evaluation of WRF simulations of clouds over the Southern Ocean with A-Train observations. Mon. Wea. Rev., 142, 647667, doi:10.1175/MWR-D-13-00128.1.

    • Search Google Scholar
    • Export Citation
  • Hurley, J. V., , and J. Galewsky, 2010a: A last saturation analysis of ENSO humidity variability in the subtropical Pacific. J. Climate, 23, 918931, doi:10.1175/2009JCLI3193.1.

    • Search Google Scholar
    • Export Citation
  • Hurley, J. V., , and J. Galewsky, 2010b: A last-saturation diagnosis of subtropical water vapor response to global warming. Geophys. Res. Lett., 37, L06702, doi:10.1029/2009GL042316.

    • Search Google Scholar
    • Export Citation
  • Iacono, M. J., , J. S. Delamere, , E. J. Mlawer, , M. W. Shephard, , S. A. Clough, , and W. D. Collins, 2008: Radiative forcing by long-lived greenhouse gases: Calculations with the AER radiative transfer models. J. Geophys. Res., 113, D13103, doi:10.1029/2008JD009944.

    • Search Google Scholar
    • Export Citation
  • Johnson, L. R., , Z. D. Sharp, , J. Galewsky, , M. Strong, , A. D. Van Pelt, , F. Dong, , and D. Noone, 2011: Hydrogen isotope correction for laser instrument measurement bias at low water vapor concentration using conventional isotope analyses: Application to measurements from Mauna Loa Observatory, Hawaii. Rapid Commun. Mass Spectrom., 25, 608616, doi:10.1002/rcm.4894.

    • Search Google Scholar
    • Export Citation
  • Jouzel, J., , and L. Merlivat, 1984: Deuterium and oxygen 18 in precipitation: Modeling of the isotopic effects during snow formation. J. Geophys. Res., 89 (D7), 11 74911 757, doi:10.1029/JD089iD07p11749.

    • Search Google Scholar
    • Export Citation
  • Kain, J. S., 2004: The Kain–Fritsch convective parameterization: An update. J. Appl. Meteor., 43, 170181, doi:10.1175/1520-0450(2004)043<0170:TKCPAU>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Krishnamurti, T. N., , M. Tewari, , D. R. Chakraborty, , J. Marengo, , P. L. Silva Dias, , and P. Satyamurty, 1999: Downstream amplification: A possible precursor to major freeze events over southeastern Brazil. Wea. Forecasting, 14, 242270, doi:10.1175/1520-0434(1999)014<0242:DAAPPT>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Kurita, N., 2011: Origin of Arctic water vapor during the ice-growth season. Geophys. Res. Lett., 38, L02709, doi:10.1029/2010GL046064.

  • Marengo, J., , A. Cornejo, , P. Satyamurty, , C. Nobre, , and W. Sea, 1997: Cold surges in tropical and extratropical South America: The strong event in June 1994. Mon. Wea. Rev., 125, 27592786, doi:10.1175/1520-0493(1997)125<2759:CSITAE>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Meyers, M. P., , P. J. Demott, , and W. R. Cotton, 1992: New primary ice-nucleation parameterizations in an explicit cloud model. J. Appl. Meteor., 31, 708721, doi:10.1175/1520-0450(1992)031<0708:NPINPI>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Morrison, A. E., , S. T. Siems, , M. J. Manton, , and A. Nazarov, 2010: A modeling case study of mixed-phase clouds over the Southern Ocean and Tasmania. Mon. Wea. Rev., 138, 839862, doi:10.1175/2009MWR3011.1.

    • Search Google Scholar
    • Export Citation
  • Moyer, E. J., , F. W. Irion, , Y. L. Yung, , and M. R. Gunson, 1996: ATMOS stratospheric deuterated water and implications for troposphere-stratosphere transport. Geophys. Res. Lett., 23, 23852388, doi:10.1029/96GL01489.

    • Search Google Scholar
    • Export Citation
  • Noone, D., 2012: Pairing measurements of the water vapor isotope ratio with humidity to deduce atmospheric moistening and dehydration in the tropical midtroposphere. J. Climate, 25, 44764494, doi:10.1175/JCLI-D-11-00582.1.

    • Search Google Scholar
    • Export Citation
  • Pierrehumbert, R., 1998: Lateral mixing as a source of subtropical water vapor. Geophys. Res. Lett., 25, 151154, doi:10.1029/97GL03563.

    • Search Google Scholar
    • Export Citation
  • Pierrehumbert, R., , H. Brogniez, , and R. Roca, 2006: On the relative humidity of the atmosphere. The Global Circulation of the Atmosphere, T. Schneider and Adam H. Sobel, Eds., Princeton University Press, 143–185.

  • Salathe, E. P., , and D. L. Hartmann, 1997: A trajectory analysis of tropical upper-tropospheric moisture and convection. J. Climate, 10, 25332547, doi:10.1175/1520-0442(1997)010<2533:ATAOTU>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Samuels-Crow, K. E., , J. Galewsky, , Z. D. Sharp, , and K. J. Dennis, 2014: Deuterium excess in subtropical free troposphere water vapor: Continuous measurements from the Chajnantor Plateau, northern Chile. Geophys. Res. Lett., 41, 86528659, doi:10.1002/2014GL062302.

    • Search Google Scholar
    • Export Citation
  • Sayres, D. S., and Coauthors, 2010: Influence of convection on the water isotopic composition of the tropical tropopause layer and tropical stratosphere. J. Geophys. Res., 115, D00J20, doi:10.1029/2009JD013100.

    • Search Google Scholar
    • Export Citation
  • Schultz, D. M., , and W. E. Bracken, 1998: Planetary- and synoptic-scale signatures associated with Central American cold surges. Mon. Wea. Rev., 126, 527, doi:10.1175/1520-0493(1998)126<0005:PASSSA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Sherwood, S. C., 1996: Maintenance of the free-tropospheric tropical water vapor distribution. Part I: Clear regime budget. J. Climate, 9, 29032918, doi:10.1175/1520-0442(1996)009<2903:MOTFTT>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Sherwood, S. C., , R. Roca, , T. M. Weckwerth, , and N. G. Andronova, 2010: Tropospheric water vapor, convection, and climate. Rev. Geophys., 48, RG2001, doi:10.1029/2009RG000301.

    • Search Google Scholar
    • Export Citation
  • Steen-Larsen, H. C., and Coauthors, 2013: Continuous monitoring of summer surface water vapor isotopic composition above the Greenland Ice Sheet. Atmos. Chem. Phys., 13 (9), 48154828, doi:10.5194/acp-13-4815-2013.

    • Search Google Scholar
    • Export Citation
  • Steen-Larsen, H. C., and Coauthors, 2014: Climatic controls on water vapor deuterium excess in the marine boundary layer of the North Atlantic based on 500 days of in situ, continuous measurements. Atmos. Chem. Phys., 14, 77417756, doi:10.5194/acp-14-7741-2014.

    • Search Google Scholar
    • Export Citation
  • Stohl, A., , S. Eckhardt, , C. Forster, , P. James, , N. Spichtinger, , and P. Seibert, 2002: A replacement for simple back trajectory calculations in the interpretation of atmospheric trace substance measurements. Atmos. Environ., 36, 46354648, doi:10.1016/S1352-2310(02)00416-8.

    • Search Google Scholar
    • Export Citation
  • Thompson, G., , R. M. Rasmussen, , and K. Manning, 2004: Explicit forecasts of winter precipitation using an improved bulk microphysics scheme. Part I: Description and sensitivity analysis. Mon. Wea. Rev., 132, 519542, doi:10.1175/1520-0493(2004)132<0519:EFOWPU>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Thompson, G., , P. R. Field, , R. M. Rasmussen, , and W. D. Hall, 2008: Explicit forecasts of winter precipitation using an improved bulk microphysics scheme. Part II: Implementation of a new snow parameterization. Mon. Wea. Rev., 136, 50955115, doi:10.1175/2008MWR2387.1.

    • Search Google Scholar
    • Export Citation
  • Uemura, R., , Y. Matsui, , K. Yoshimura, , H. Motoyama, , and N. Yoshida, 2008: Evidence of deuterium excess in water vapor as an indicator of ocean surface conditions. J. Geophys. Res.,113, D19114, doi:10.1029/2008JD010209.

  • Webster, C., , and A. Heymsfield, 2003: Water isotope ratios D/H, 18O/16O, 17O/16O in and out of clouds map dehydration pathways. Science, 302, 17421745, doi:10.1126/science.1089496.

    • Search Google Scholar
    • Export Citation
  • Wootten, A., , and A. R. Thompson, 2009: The Atacama Large Millimeter/Submillimeter Array. Proc. IEEE, 97, 14631471, doi:10.1109/JPROC.2009.2020572.

    • Search Google Scholar
    • Export Citation
  • Worden, J., , D. Noone, , K. Bowman, , and R. Beer, 2007: Importance of rain evaporation and continental convection in the tropical water cycle. Nature, 445, 528532, doi:10.1038/nature05508.

    • Search Google Scholar
    • Export Citation
  • Wright, J. S., , A. Sobel, , and J. Galewsky, 2010: Diagnosis of zonal mean relative humidity changes in a warmer climate. J. Climate, 23, 45564569, doi:10.1175/2010JCLI3488.1.

    • Search Google Scholar
    • Export Citation
  • Wu, M. C., , and J. Chan, 1995: Surface features of winter monsoon surges over South China. Mon. Wea. Rev., 123, 662680, doi:10.1175/1520-0493(1995)123<0662:SFOWMS>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Wu, M. C., , and J. Chan, 1997: Upper-level features associated with winter monsoon surges over South China. Mon. Wea. Rev., 125, 317340, doi:10.1175/1520-0493(1997)125<0317:ULFAWW>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Yang, H., , and R. Pierrehumbert, 1994: Production of dry air by isentropic mixing. J. Atmos. Sci., 51, 34373454, doi:10.1175/1520-0469(1994)051<3437:PODABI>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 9 9 5
PDF Downloads 6 6 4

Constraining Supersaturation and Transport Processes in a South American Cold-Air Outbreak Using Stable Isotopologues of Water Vapor

View More View Less
  • 1 Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, New Mexico
© Get Permissions
Restricted access

Abstract

In situ measurements of water vapor isotopic composition from the subtropical Chilean Andes, supported by mesoscale model simulations and diagnostic analyses, document the processes governing the transport of dry air and isotopically depleted water vapor from the midlatitudes into the subtropics during a South American cold-air surge in July 2014. On 23 July 2014, temperatures on the Chajnantor Plateau reached −18°C, among the lowest temperatures on record for the site. On 26 July 2014, water vapor δD and δ18O reached a low of −538 ± 1.6‰ and −71.7 ± 0.2‰, among the lowest values on record. Numerical simulations show that the dynamics of the event were consistent with previous studies of South American cold-air outbreaks. Back-trajectory analyses show that the isotopically depleted water vapor that reached Chajnantor on July 26 was last saturated over the South Pacific on July 23 at 300 hPa at a temperature of about −50°C under ice supersaturation with RHice of about 110%. The water vapor traveled to Chajnantor along a nearly isentropic path following saturation. Modeling of the isotopic data require condensation at temperatures between −50°C and −53°C under supersaturation with RHice between 112% and 118%, followed by less than 25% moistening during transport. These results show that measurements of water vapor isotopic composition can provide observational constraints on in-cloud processes that influence the humidity of the subtropics.

Denotes Open Access content.

Corresponding author address: Joseph Galewsky, Department of Earth and Planetary Sciences, University of New Mexico, 221 Yale Blvd. NE, Albuquerque, NM 87131. E-mail: galewsky@unm.edu

Abstract

In situ measurements of water vapor isotopic composition from the subtropical Chilean Andes, supported by mesoscale model simulations and diagnostic analyses, document the processes governing the transport of dry air and isotopically depleted water vapor from the midlatitudes into the subtropics during a South American cold-air surge in July 2014. On 23 July 2014, temperatures on the Chajnantor Plateau reached −18°C, among the lowest temperatures on record for the site. On 26 July 2014, water vapor δD and δ18O reached a low of −538 ± 1.6‰ and −71.7 ± 0.2‰, among the lowest values on record. Numerical simulations show that the dynamics of the event were consistent with previous studies of South American cold-air outbreaks. Back-trajectory analyses show that the isotopically depleted water vapor that reached Chajnantor on July 26 was last saturated over the South Pacific on July 23 at 300 hPa at a temperature of about −50°C under ice supersaturation with RHice of about 110%. The water vapor traveled to Chajnantor along a nearly isentropic path following saturation. Modeling of the isotopic data require condensation at temperatures between −50°C and −53°C under supersaturation with RHice between 112% and 118%, followed by less than 25% moistening during transport. These results show that measurements of water vapor isotopic composition can provide observational constraints on in-cloud processes that influence the humidity of the subtropics.

Denotes Open Access content.

Corresponding author address: Joseph Galewsky, Department of Earth and Planetary Sciences, University of New Mexico, 221 Yale Blvd. NE, Albuquerque, NM 87131. E-mail: galewsky@unm.edu
Save