• Aemisegger, F., Sturm P. , Graf P. , Sodemann H. , Pfahl S. , Knohl A. , and Wernli H. , 2012: Measuring variations of δ18O and δ2H in atmospheric water vapour using two commercial laser-based spectrometers: An instrument characterisation study. Atmos. Meas. Tech., 5, 14911511, doi:10.5194/amt-5-1491-2012.

    • Search Google Scholar
    • Export Citation
  • Bastrikov, V., Steen-Larsen H.-C. , Masson-Delmotte V. , Gribanov K. , Cattani O. , Jouzel J. , and Zakharov V. , 2014: Continuous measurements of atmospheric water vapour isotopes in western Siberia (Kourovka). Atmos. Meas. Tech., 7, 17631776, doi:10.5194/amt-7-1763-2014.

    • Search Google Scholar
    • Export Citation
  • Benetti, M., Reverdin G. , Pierre C. , Merlivat L. , Risi C. , Steen-Larsen H. C. , and Vimeux F. , 2014: Deuterium excess in marine water vapor: Dependency on relative humidity and surface wind speed during evaporation. J. Geophys. Res. Atmos., 119, 584593, doi:10.1002/2013JD020535.

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

    • Search Google Scholar
    • Export Citation
  • Blossey, P. N., and Coauthors, 2015: Isotopic Fractionation in Snow (IFRACS) at Storm Peak Laboratory. 2015 Fall Meeting, San Francisco, CA, Amer. Geophys. Union, Abstract PP11B-2224.

  • Bolot, M., Legras B. , and Moyer E. J. , 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
  • Bond, T. C., Anderson T. L. , and Campbell D. , 1999: Calibration and intercomparison of filter-based measurements of visible light absorption by aerosols. Aerosol Sci. Technol., 30, 582600, doi:10.1080/027868299304435.

    • Search Google Scholar
    • Export Citation
  • Borys, R. D., and Wetzel M. A. , 1997: Storm Peak Laboratory: A research, teaching, and service facility for the atmospheric sciences. Bull. Amer. Meteor. Soc., 78, 21152123, doi:10.1175/1520-0477(1997)078<2115:SPLART>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Borys, R. D., Lowenthal D. H. , and Rahn K. A. , 1986: Contributions of smelters and other sources to pollution sulfate at a mountaintop site in northwestern Colorado. Acid Deposition in Colorado—A Potential or Current Problem; Local versus Long-Distance Transport into the State, R. Pielke, Ed., Colorado State University, 167–174.

  • Borys, R. D., Hindman E. E. , and DeMott P. J. , 1988: The chemical fractionation of atmospheric aerosols as a result of snow crystal formation and growth. J. Atmos. Chem., 7, 213239, doi:10.1007/BF00130931.

    • Search Google Scholar
    • Export Citation
  • Borys, R. D., Lowenthal D. H. , and Mitchell D. L. , 2000: The relationships among cloud microphysics, chemistry, and precipitation rate in cold mountain clouds. Atmos. Environ., 34, 25932602, doi:10.1016/S1352-2310(99)00492-6.

    • Search Google Scholar
    • Export Citation
  • Borys, R. D., Lowenthal D. H. , Cohn S. A. , and Brown W. O. J. , 2003: Mountaintop and radar measurements of aerosol effects on snow growth and snowfall rate. Geophys. Res. Lett., 30, 1538, doi:10.1029/2002GL016855.

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

    • Search Google Scholar
    • Export Citation
  • Clark, I., and Fritz P. , 1997: Environmental Isotopes in Hydrology. CRC Press/Lewis Publishers, 328 pp.

  • Colle, B. A., Wolfe J. B. , Steenburgh W. J. , Kingsmill D. E. , Cox J. A. , and Shafer J. C. , 2005: High-resolution simulations and microphyscial validation of an orographic precipitation event over the Wasatch Mountains during IPEX IOP3. Mon. Wea. Rev., 133, 29472971, doi:10.1175/MWR3017.1.

    • Search Google Scholar
    • Export Citation
  • Craig, H., 1961: Isotopic variations in meteoric waters. Science, 133, 17021703, doi:10.1126/science.133.3465.1702.

  • Dansgaard, W., 1964: Stable isotopes in precipitation. Tellus, 16A, 436468, doi:10.1111/j.2153-3490.1964.tb00181.x.

  • Dansgaard, W., White J. W. C. , and Johnsen S. J. , 1989: The abrupt termination of the Younger Dryas climate event. Nature, 339, 532534, doi:10.1038/339532a0.

    • Search Google Scholar
    • Export Citation
  • Delanoe, J. M., Heymsfield A. J. , Protat A. , Bansemer A. R. , and Hogan R. J. , 2014: Normalized particle size distribution for remote sensing application. J. Geophys. Res. Atmos., 119, 42044227, doi:10.1002/2013JD020700.

    • Search Google Scholar
    • Export Citation
  • Demoz, B. B., Warburton J. A. , and Stone R. H. , 1991: The influence of riming on the oxygen isotopic composition of ice-phase precipitation. Atmos. Res., 26, 463488, doi:10.1016/0169-8095(91)90039-Y.

    • Search Google Scholar
    • Export Citation
  • Draxler, R. R., and Rolph G. D. , 2015: HYSPLIT model access. NOAA Air Resources Laboratory. [Available online at http://www.arl.noaa.gov/HYSPLIT.php.]

  • Ellehoj, M. D., Steen-Larsen H. C. , Johnsen S. J. , and Madsen M. B. , 2013: Ice-vapor equilibrium fractionation factor of hydrogen and oxygen isotopes: Experimental investigations and implications for stable water isotope studies. Rapid Commun. Mass Spectrom., 27, 21492158, doi:10.1002/rcm.6668.

    • Search Google Scholar
    • Export Citation
  • Gedzelman, S. D., and Lawrence J. R. , 1990: The isotopic composition of precipitation from two extratropical cyclones. Mon. Wea. Rev., 118, 495509, doi:10.1175/1520-0493(1990)118<0495:TICOPF>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Gedzelman, S. D., and Arnold R. , 1994: Modeling the isotopic composition of precipitation. J. Geophys. Res., 99, 10 45510 471, doi:10.1029/93JD03518.

    • Search Google Scholar
    • Export Citation
  • Hallar, A. G., Mccubbin I. B. , Novosselov I. , Gorder R. , and Ogren J. , 2016: A high elevation aerosol manifold modeling study and inter-comparison. 2012 Fall Meeting, San Francisco, CA, Amer. Geophys. Union, Abstract A51A-0016.

  • Harmon, R. S., 1979: An isotopic study of groundwater seepage in the central Kentucky Karst. Water Resour. Res., 15, 476480, doi:10.1029/WR015i002p00476.

    • Search Google Scholar
    • Export Citation
  • Heymsfield, A. J., Schmitt C. , and Bansemer A. , 2013: Ice cloud particle size distributions and pressure-dependent terminal velocities from in situ observations at temperatures from 0° to −86°C. J. Atmos. Sci., 70, 41234154, doi:10.1175/JAS-D-12-0124.1.

    • Search Google Scholar
    • Export Citation
  • Hindman, E. E., Carter E. J. , Borys R. D. , and Mitchell D. L. , 1992: Collecting super-cooled droplets as a function of droplet size. J. Atmos. Oceanic Technol., 9, 337353, doi:10.1175/1520-0426(1992)009<0337:CSCDAA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Hobbs, P. V., 1975: The nature of winter clouds and precipitation in the Cascade Mountains and their modification by artificial seeding. Part I: Natural conditions. J. Appl. Meteor., 14, 783804, doi:10.1175/1520-0450(1975)014<0783:TNOWCA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Houze, R. A., and Medina S. , 2005: Turbulence as a mechanism for orographic precipitation enhancement. J. Atmos. Sci., 62, 35993623, doi:10.1175/JAS3555.1.

    • Search Google Scholar
    • Export Citation
  • Joussaume, S., Sadourny R. , and Jouzel J. , 1984: A general circulation model of water isotope cycles in the atmosphere. Nature, 311, 2429, doi:10.1038/311024a0.

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

    • Search Google Scholar
    • Export Citation
  • Jouzel, J., Merlivat L. , and Lorius C. , 1982: Deuterium excess in an East Antarctic ice core suggests higher relative humidity at the oceanic surface during the last glacial maximum. Nature, 299, 688691, doi:10.1038/299688a0.

    • Search Google Scholar
    • Export Citation
  • Jouzel, J., and Coauthors, 2007: The GRIP deuterium-excess record. Quat. Sci. Rev., 26, 117, doi:10.1016/j.quascirev.2006.07.015.

  • Kumler, A., and Ogren J. , 2016: A comparison of inlet setups at Storm Peak Laboratory. NOAA, 1 p. [Available online at http://www.esrl.noaa.gov/gmd/publications/annual_meetings/2016/abstracts/24-160406-B.pdf.]

  • Kusunoki, K., Murakami M. , Orikasa N. , Hoshimoto M. , Tanaka Y. , Mizuno H. , Hamazu K. , and Watanabe H. , 2005: Observations of quasi-stationary and shallow orographic snow clouds: Spatial distributions of supercooled liquid water and snow particles. Mon. Wea. Rev., 133, 743751, doi:10.1175/MWR2874.1.

    • Search Google Scholar
    • Export Citation
  • Lamb, D., Nielsen K. W. , Klieforth H. E. , and Hallett J. , 1976: Measurement of liquid water content in cloud systems over the Sierra Nevada. J. Appl. Meteor., 15, 763775, doi:10.1175/1520-0450(1976)015<0763:MOLWCI>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Lee, J.-E., Pierrehumbert R. , Swann A. , and Linter B. R. , 2009a: Sensitivity of stable water isotopic values to convective parameterization schemes. Geophys. Res. Lett., 36, L23801, doi:10.1029/2009GL040880.

    • Search Google Scholar
    • Export Citation
  • Lee, J.-E., Johnson K. , and Fung I. , 2009b: Precipitation over South America during the Last Glacial Maximum: An analysis of the “amount effect” with a water isotope-enabled general circulation model. Geophys. Res. Lett., 36, L19701, doi:10.1029/2009GL039265.

    • Search Google Scholar
    • Export Citation
  • Lorius, C., Merlivat L. , Jouzel J. , and Pourchet M. , 1979: A 30,000 yr isotopic climate record from Antarctic ice. Nature, 280, 644648, doi:10.1038/280644a0.

    • Search Google Scholar
    • Export Citation
  • Lowenthal, D. H., Hanumara R. C. , Rahn K. A. , and Currie L. A. , 1987: Effects of systematic error, estimates and uncertainties in chemical mass balance apportionments: Quail Roost II revisited. Atmos. Environ., 21, 501510, doi:10.1016/0004-6981(87)90033-3.

    • Search Google Scholar
    • Export Citation
  • Lowenthal, D. H., Borys R. D. , and Wetzel M. A. , 2002: Aerosol distributions and cloud interactions at a mountaintop laboratory. J. Geophys. Res., 107, doi:10.1029/2001JD002046.

    • Search Google Scholar
    • Export Citation
  • Lowenthal, D. H., Borys R. D. , Cotton W. , Saleeby S. , Cohn S. A. , and Brown W. O. J. , 2011: The altitude of snow growth by riming and vapor deposition in mixed-phase orographic clouds. Atmos. Environ., 45, 519522, doi:10.1016/j.atmosenv.2010.09.061.

    • Search Google Scholar
    • Export Citation
  • Majoube, M., 1971: Fractionnement en oxygène-18 et en deutérium entre l’eau et sa vapeur. J. Chim. Phys., 68, 14231436.

  • Masson-Delmotte, V., and Coauthors, 2008: A review of Antarctic surface snow isotopic composition: Observations, atmospheric circulation, and isotopic modeling. J. Climate, 21, 33593387, doi:10.1175/2007JCLI2139.1.

    • Search Google Scholar
    • Export Citation
  • Merlivat, L., 1978: Molecular diffusivities of H2 16 0, HD16 0, and H2 18 0 in gases. J. Chem. Phys., 69, 28642871, doi:10.1063/1.436884.

    • Search Google Scholar
    • Export Citation
  • Moore, M., Blossey P. , Muhlbauer A. , and Kuang Z. , 2016: Microphysical controls on the isotopic composition of wintertime orographic precipitation. J. Geophys. Res. Atmos., 121, 72357253, doi:10.1002/2015JD023763.

    • Search Google Scholar
    • Export Citation
  • Muhlbauer, A., Hashino T. , Xue L. , Teller A. , Lohmann U. , Rasmussen R. M. , Geresdi I. , and Pan Z. , 2010: Intercomparison of aerosol-cloud-precipitation interactions in stratiform orographic mixed-phase clouds. Atmos. Chem. Phys., 10, 81738196, doi:10.5194/acp-10-8173-2010.

    • Search Google Scholar
    • Export Citation
  • Noone, D., and Simmonds I. , 2002: Associations between δ18O of water and climate parameters in a simulation of atmospheric circulation for 1979–95. J. Climate, 15, 31503169, doi:10.1175/1520-0442(2002)015<3150:ABOOWA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Noone, D., and Coauthors, 2013: Determining water sources in the boundary layer from tall tower profiles of water vapor and surface water isotope ratios after a snowstorm in Colorado. Atmos. Chem. Phys., 13, 16071623, doi:10.5194/acp-13-1607-2013.

    • Search Google Scholar
    • Export Citation
  • Obrist, D., Hallar A. G. , McCubbin I. , Stephens B. B. , and Rahn T. , 2008: Atmospheric mercury concentrations at Storm Peak Laboratory in the Rocky Mountains: Evidence for long-range transport from Asia, boundary layer contributions, and plant mercury uptake. Atmos. Environ., 42, 75797589, doi:10.1016/j.atmosenv.2008.06.051.

    • Search Google Scholar
    • Export Citation
  • Pausata, F. S. R., Battisti D. S. , Nisancioglu K. H. , and Bitz C. M. , 2011: Chinese stalagmite controlled by changes in the Indian monsoon during a simulated Heinrich event. Nat. Geosci., 4, 474480, doi:10.1038/ngeo1169.

    • Search Google Scholar
    • Export Citation
  • Pfahl, S., and Sodemann H. , 2014: What controls deuterium excess in global precipitation? Climate Past, 10, 771781, doi:10.5194/cp-10-771-2014.

    • Search Google Scholar
    • Export Citation
  • Pfahl, S., Wernli H. , and Yoshimura K. , 2012: The isotopic composition of precipitation from a winter storm—A case study with the limited-area model COSMOiso. Atmos. Chem. Phys., 12, 16291648, doi:10.5194/acp-12-1629-2012.

    • Search Google Scholar
    • Export Citation
  • Picciotto, E., De Maere X. , and Friedman I. , 1960: Isotopic composition and temperature of formation of Antarctic snows. Nature, 187, 857859, doi:10.1038/187857a0.

    • Search Google Scholar
    • Export Citation
  • Poage, M. A., and Chamberlain C. P. , 2001: Empirical relationships between elevation and the stable isotope composition of precipitation and surface waters: Considerations for studies of paleoelevation change. Amer. J. Sci., 301, 115, doi:10.2475/ajs.301.1.1.

    • Search Google Scholar
    • Export Citation
  • Rauber, R. M., and Grant L. O. , 1986a: The characteristics and distribution of cloud water over the mountains of northern Colorado during wintertime storms. Part II: Microphysical characteristics. J. Climate Appl. Meteor., 25, 489504, doi:10.1175/1520-0450(1986)025<0489:TCADOC>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Rauber, R. M., Grant L. O. , Feng D. , and Snider J. B. , 1986b: The characteristics and distribution of cloud water over the mountains of northern Colorado during wintertime storms. Part I: temporal variations. J. Climate Appl. Meteor., 25, 468488, doi:10.1175/1520-0450(1986)025<0468:TCADOC>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Reinking, R. F., Snider J. B. , and Coen J. L. , 2000: Influences of storm-embedded orographic gravity waves on cloud liquid water and precipitation. J. Appl. Meteor., 39, 733759, doi:10.1175/1520-0450(2000)039<0733:IOSEOG>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Risi, C., Bony S. , Vimeux F. , Frankenberg C. , Noone D. , and Worden J. , 2010: Understanding the Sahelian water budget through the isotopic composition of water vapor and precipitation. J. Geophys. Res., 115, D24110, doi:10.1029/2010JD014690.

    • Search Google Scholar
    • Export Citation
  • Rotunno, R., and Houze R. A. , 2007: Lessons on orographic precipitation from the Mesoscale Alpine Programme. Quart. J. Roy. Meteor. Soc., 133, 811830, doi:10.1002/qj.67.

    • Search Google Scholar
    • Export Citation
  • Rowley, D. B., Pierrehumbert R. T. , and Currie B. S. , 2001: A new approach to stable isotope-based paleoaltimetry: Implication for paleoaltimetry and paleohypsometry of the high Himalaya since the Late Miocene. Earth Planet. Sci. Lett., 188, 253268, doi:10.1016/S0012-821X(01)00324-7.

    • Search Google Scholar
    • Export Citation
  • Saleeby, S. M., Cotton W. R. , Lowenthal D. , Messina J. , and Benedict K. B. , 2013: Aerosol impacts on the microphysical growth processes of orographic snowfall. J. Appl. Meteor. Climatol., 52, 834852, doi:10.1175/JAMC-D-12-0193.1.

    • Search Google Scholar
    • Export Citation
  • Samuels-Crow, K. E., Galewsky J. , Sharp Z. D. , and Dennis K. J. , 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
  • Schmidt, G. A., Hoffmann G. , Shindell D. T. , and Hu Y. , 2005: Modeling atmospheric stable water isotopes and the potential for constraining cloud processes and stratosphere-troposphere water exchange. J. Geophys. Res., 110, D21314, doi:10.1029/2005JD005790.

    • Search Google Scholar
    • Export Citation
  • Scholl, M. A., Giambelluca T. W. , Gingerich S. B. , Nullet M. A. , and Loope L. L. , 2007: Cloud water in windward and leeward mountain forests: The stable isotope signature of orographic cloud water. Water Resour. Res., 43, W12411, doi:10.1029/2007WR006011.

    • Search Google Scholar
    • Export Citation
  • Siegenthaler, U., and Oeschger H. , 1980: Correlation of 18O in precipitation with temperature and altitude. Nature, 285, 314317, doi:10.1038/285314a0.

    • Search Google Scholar
    • Export Citation
  • Smith, J. A., Ackerman A. S. , Jensen E. J. , and Toon O. B. , 2006: Role of deep convection in establishing the isotopic composition of water vapor in the tropical transition layer. Geophys. Res. Lett., 33, L06812, doi:10.1029/2005GL024078.

    • Search Google Scholar
    • Export Citation
  • Smith, R. B., and Evans J. P. , 2007: Orographic precipitation and water vapor fractionation over the southern Andes. J. Hydrometeor., 8, 319, doi:10.1175/JHM555.1.

    • Search Google Scholar
    • Export Citation
  • Smith, R. B., Barstad I. , and Bonneau L. , 2005: Oregon’s precipitation and Oregon’s climate transition. J. Atmos. Sci., 62, 177191, doi:10.1175/JAS-3376.1.

    • Search Google Scholar
    • Export Citation
  • Steen-Larsen, H. C., and Coauthors, 2011: Understanding the climate signal in the water stable isotope records from the NEEM shallow firn/ice cores in northwest Greenland. J. Geophys. Res., 116, D06108, doi:10.1029/2010JD014311.

    • 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
  • Steen-Larsen, H. C., and Coauthors, 2015: Moisture sources and synoptic to seasonal variability of North Atlantic water vapor isotopic composition. J. Geophys. Res. Atmos., 120, 57575774, doi:10.1002/2015JD023234.

    • Search Google Scholar
    • Export Citation
  • Stewart, M. K., 1975: Stable isotope fractionation due to evaporation and isotopic exchange of falling waterdrops: Applications to atmospheric processes and evaporation of lakes. J. Geophys. Res., 80, 11331146, doi:10.1029/JC080i009p01133.

    • Search Google Scholar
    • Export Citation
  • Sturm, C., Hoffman G. , and Langmann B. , 2007: Simulation of stable water isotopes in precipitation over South America: Comparing regional to global circulation models. J. Climate, 20, 37303750, doi:10.1175/JCLI4194.1.

    • Search Google Scholar
    • Export Citation
  • Vaisala, 2013: Humidity conversion formulas. Vaisala Oyj Doc. B210973EN-F, 17 pp. [Available online at http://www.vaisala.com/Vaisala%20Documents/Application%20notes/Humidity_Conversion_Formulas_B210973EN-F.pdf.]

  • Vimeux, F., Masson V. , Jouzel J. , Stievenard M. , and Petit J. R. , 1999: Glacial–interglacial changes in ocean surface conditions in the Southern Hemisphere. Nature, 398, 410413, doi:10.1038/18860.

    • Search Google Scholar
    • Export Citation
  • Warburton, J. A., and DeFelice T. P. , 1986: Oxygen isotopic composition of central Sierra Nevada precipitation, I. Identification of ice-phase water capture regions in winter storms. Atmos. Res., 20, 1122, doi:10.1016/0169-8095(86)90004-9.

    • Search Google Scholar
    • Export Citation
  • Welp, L. R., and Coauthors, 2012: A meta-analysis of water vapor deuterium-excess in the midlatitude atmospheric surface layer. Global Biogeochem. Cycles, 26, GB3021, doi:10.1029/2011GB004246.

    • Search Google Scholar
    • Export Citation
  • Werner, M., Langebroek P. M. , Carlsen T. , Herold M. , and Lohmann G. , 2011: Stable water isotopes in the ECHAM5 general circulation model: Toward a high-resolution isotope modeling on a global scale. J. Geophys. Res., 116, D15109, doi:10.1029/2011JD015681.

    • Search Google Scholar
    • Export Citation
  • Wetzel, M., and Coauthors, 2004: Mesoscale snowfall prediction and verification in mountainous terrain. Wea. Forecasting, 19, 806828, doi:10.1175/1520-0434(2004)019<0806:MSPAVI>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Wright, J. S., Sobel A. H. , and Schmidt G. A. , 2009: Influence of condensate evaporation on water vapor and its stable isotopes in a GCM. Geophys. Res. Lett., 36, L12804, doi:10.1029/2009GL038091.

    • Search Google Scholar
    • Export Citation
  • Yoshimura, K., Frankenberg C. , Lee J. , Kanamitsu M. , Worden J. , and Röckmann T. , 2011: Comparison of an isotopic atmospheric general circulation model with new quasi-global satellite measurements of water vapor isotopologues. J. Geophys. Res., 116, D19118, doi:10.29/2011JD016035.

    • Search Google Scholar
    • Export Citation
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Isotopic Fractionation in Wintertime Orographic Clouds

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  • 1 Desert Research Institute, Reno, Nevada
  • | 2 University of Washington, Seattle, Washington
  • | 3 Harvard University, Cambridge, Massachusetts
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Abstract

The Isotopic Fractionation in Snow (IFRACS) study was conducted at Storm Peak Laboratory (SPL) in northwestern Colorado during the winter of 2014 to elucidate snow growth processes in mixed-phase clouds. The isotopic composition (δ18O and δD) of water vapor, cloud water, and snow in mixed-phase orographic clouds were measured simultaneously for the first time. The depletion of heavy isotopes [18O and deuterium (D)] was greatest for vapor, followed by snow, then cloud. The vapor, cloud, and snow compositions were highly correlated, suggesting similar cloud processes throughout the experiment. The isotopic composition of the water vapor was directly related to its concentration. Isotopic fractionation during condensation of vapor to cloud drops was accurately reproduced assuming equilibrium fractionation. This was not the case for snow, which grows by riming and vapor deposition. This implies stratification of vapor with altitude. The relationship between temperature at SPL and δ18O was used to show that the snow gained most of its mass within 922 m above SPL. Relatively invariant deuterium excess (d) in vapor, cloud water, and snow from day to day suggests a constant vapor source and Rayleigh fractionation during transport. The diurnal variation of vapor d reflected the differences between surface and free-tropospheric air during the afternoon and early morning hours, respectively. These observations will be used to validate simulations of snow growth using an isotope-enabled mesoscale model with explicit microphysics.

Corresponding author e-mail: Douglas Lowenthal, dougl@dri.edu

Abstract

The Isotopic Fractionation in Snow (IFRACS) study was conducted at Storm Peak Laboratory (SPL) in northwestern Colorado during the winter of 2014 to elucidate snow growth processes in mixed-phase clouds. The isotopic composition (δ18O and δD) of water vapor, cloud water, and snow in mixed-phase orographic clouds were measured simultaneously for the first time. The depletion of heavy isotopes [18O and deuterium (D)] was greatest for vapor, followed by snow, then cloud. The vapor, cloud, and snow compositions were highly correlated, suggesting similar cloud processes throughout the experiment. The isotopic composition of the water vapor was directly related to its concentration. Isotopic fractionation during condensation of vapor to cloud drops was accurately reproduced assuming equilibrium fractionation. This was not the case for snow, which grows by riming and vapor deposition. This implies stratification of vapor with altitude. The relationship between temperature at SPL and δ18O was used to show that the snow gained most of its mass within 922 m above SPL. Relatively invariant deuterium excess (d) in vapor, cloud water, and snow from day to day suggests a constant vapor source and Rayleigh fractionation during transport. The diurnal variation of vapor d reflected the differences between surface and free-tropospheric air during the afternoon and early morning hours, respectively. These observations will be used to validate simulations of snow growth using an isotope-enabled mesoscale model with explicit microphysics.

Corresponding author e-mail: Douglas Lowenthal, dougl@dri.edu
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