Editorial Type:
Article
Article Type:
Research Article

Dual-Polarization Radar Data Analysis of the Impact of Ground-Based Glaciogenic Seeding on Winter Orographic Clouds. Part I: Mostly Stratiform Clouds

Xiaoqin Jing Department of Atmospheric Science, University of Wyoming, Laramie, Wyoming

Search for other papers by Xiaoqin Jing in
Current site
Google Scholar
PubMed Close
,
Bart Geerts Department of Atmospheric Science, University of Wyoming, Laramie, Wyoming

Search for other papers by Bart Geerts in
Current site
Google Scholar
PubMed Close
,
Katja Friedrich Department of Atmospheric and Oceanic Sciences, University of Colorado Boulder, Boulder, Colorado

Search for other papers by Katja Friedrich in
Current site
Google Scholar
PubMed Close
, and
Binod Pokharel Department of Atmospheric Science, University of Wyoming, Laramie, Wyoming

Search for other papers by Binod Pokharel in
Current site
Google Scholar
PubMed Close
Print Publication:
01 Sep 2015
DOI:
https://doi.org/10.1175/JAMC-D-14-0257.1
Page(s):
1944–1969
Restricted access

Abstract

The impact of ground-based glaciogenic seeding on wintertime orographic, mostly stratiform clouds is analyzed by means of data from an X-band dual-polarization radar, the Doppler-on-Wheels (DOW) radar, positioned on a mountain pass. This study focuses on six intensive observation periods (IOPs) during the 2012 AgI Seeding Cloud Impact Investigation (ASCII) project in Wyoming. In all six storms, the bulk upstream Froude number below mountaintop exceeded 1 (suggesting unblocked flow), the clouds were relatively shallow (with bases below freezing), some liquid water was present, and orographic flow conditions were mostly steady. To examine the silver iodide (AgI) seeding effect, three study areas are defined (a control area, a target area upwind of the crest, and a lee target area), and comparisons are made between measurements from a treated period and those from an untreated period. Changes in reflectivity and differential reflectivity observed by the DOW at low levels during seeding are consistent with enhanced snow growth, by vapor diffusion and/or aggregation, for a case study and for the composite analysis of all six IOPs, especially at close range upwind of the mountain crest. These low-level changes may have been affected by natural changes aloft, however, as evident from differences in the evolution of the echo-top height in the control and target areas. Even though precipitation in the target region is strongly correlated with that in the control region, the authors cannot definitively attribute the change to seeding because there is a lack of knowledge about natural variability, nor can the outcome be generalized, because the sample size is small.

Corresponding author address: Xiaoqin Jing, Dept. of Atmospheric Science, University of Wyoming, 1000 E. University Ave., Laramie, WY 82071. E-mail: xjing@uwyo.edu

Abstract

The impact of ground-based glaciogenic seeding on wintertime orographic, mostly stratiform clouds is analyzed by means of data from an X-band dual-polarization radar, the Doppler-on-Wheels (DOW) radar, positioned on a mountain pass. This study focuses on six intensive observation periods (IOPs) during the 2012 AgI Seeding Cloud Impact Investigation (ASCII) project in Wyoming. In all six storms, the bulk upstream Froude number below mountaintop exceeded 1 (suggesting unblocked flow), the clouds were relatively shallow (with bases below freezing), some liquid water was present, and orographic flow conditions were mostly steady. To examine the silver iodide (AgI) seeding effect, three study areas are defined (a control area, a target area upwind of the crest, and a lee target area), and comparisons are made between measurements from a treated period and those from an untreated period. Changes in reflectivity and differential reflectivity observed by the DOW at low levels during seeding are consistent with enhanced snow growth, by vapor diffusion and/or aggregation, for a case study and for the composite analysis of all six IOPs, especially at close range upwind of the mountain crest. These low-level changes may have been affected by natural changes aloft, however, as evident from differences in the evolution of the echo-top height in the control and target areas. Even though precipitation in the target region is strongly correlated with that in the control region, the authors cannot definitively attribute the change to seeding because there is a lack of knowledge about natural variability, nor can the outcome be generalized, because the sample size is small.

Corresponding author address: Xiaoqin Jing, Dept. of Atmospheric Science, University of Wyoming, 1000 E. University Ave., Laramie, WY 82071. E-mail: xjing@uwyo.edu
Save
Cover Journal of Applied Meteorology and Climatology
Journal of Applied Meteorology and Climatology

  • Boe, B. A., J. A. Heimbach, T. W. Krauss, L. Xue, X. Chu, and J. T. McPartland, 2014: The dispersion of silver iodide particles from ground-based generators over complex terrain. Part I: Observations with acoustic ice nucleus counters. J. Appl. Meteor. Climatol., 53, 1325–1341, doi:10.1175/JAMC-D-13-0240.1.

    • Search Google Scholar
    • Export Citation

  • Boudala, F. S., G. A. Isaac, S. G. Cober, and Q. Fu, 2004: Liquid fraction in stratiform mixed-phase clouds from in situ observations. Quart. J. Roy. Meteor. Soc., 130, 2919–2931, doi:10.1256/qj.03.153.

    • Search Google Scholar
    • Export Citation

  • Breed, D., R. Rasmussen, C. Weeks, B. Boe, and T. Deshler, 2014: Evaluating winter orographic cloud seeding: Design of the Wyoming Weather Modification Pilot Project (WWMPP). J. Appl. Meteor. Climatol., 53, 282–299, doi:10.1175/JAMC-D-13-0128.1.

    • Search Google Scholar
    • Export Citation

  • Bruintjes, R. T., 1999: A review of cloud seeding experiments to enhance precipitation and some new prospects. Bull. Amer. Meteor. Soc., 80, 805–820, doi:10.1175/1520-0477(1999)080<0805:AROCSE>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Chu, X., L. Xue, B. Geerts, R. Rasmussen, and D. Breed, 2014: A case study of radar observations and WRF LES simulations of the impact of ground-based glaciogenic seeding on orographic clouds and precipitation. Part I: Observations and model validations. J. Appl. Meteor. Climatol., 53, 2264–2286, doi:10.1175/JAMC-D-14-0017.1.

    • Search Google Scholar
    • Export Citation

  • Colle, B. A., 2004: Sensitivity of orographic precipitation to changing ambient conditions and terrain geometries: An idealized modeling perspective. J. Atmos. Sci., 61, 588–606, doi:10.1175/1520-0469(2004)061<0588:SOOPTC>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Cunningham, J. G., and S. E. Yuter, 2014: Instability characteristics of radar-derived mesoscale organization modes within cool-season precipitation near Portland, Oregon. Mon. Wea. Rev., 142, 1738–1757, doi:10.1175/MWR-D-13-00133.1.

    • Search Google Scholar
    • Export Citation

  • Dennis, A. S., A. Koscielski, D. E. Cain, J. H. Hirsch, and P. L. Smith, 1975: Analysis of radar observations of a randomized cloud seeding experiment. J. Appl. Meteor., 14, 897–908, doi:10.1175/1520-0450(1975)014<0897:AOROOA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • DeMott, P. J., 1997: Report to North Dakota Atmospheric Resource Board and Weather Modification Incorporated on tests of the ice nucleating ability of aerosols produced by the Lohse Airborne Generator. Colorado State University Dept. of Atmospheric Science Tech. Rep., 38 pp.

  • Deshler, T., D. W. Reynolds, and A. W. Huggins, 1990: Physical response of winter orographic clouds over the Sierra Nevada to airborne seeding using dry ice or silver iodide. J. Appl. Meteor., 29, 288–330, doi:10.1175/1520-0450(1990)029<0288:PROWOC>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Durran, D. R., 1986: Another look at downslope windstorms. Part I: The development of analogs to supercritical flow in an infinitely deep, continuously stratified fluid. J. Atmos. Sci., 43, 2527–2543, doi:10.1175/1520-0469(1986)043<2527:ALADWP>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Gabriel, K. R., 1999: Ratio statistics for randomized experiments in precipitation stimulation. J. Appl. Meteor., 38, 290–301, doi:10.1175/1520-0450(1999)038<0290:RSFREI>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Gagin, A., 1986: Evaluation of “static” and “dynamic” seeding concepts through analyses of Israeli II and FACE-2 experiments. Precipitation Enhancement—A Scientific Challenge, Meteor. Monogr., No. 43, Amer. Meteor. Soc., 63–76.

  • Gagin, A., D. Rosenfeld, W. L. Woodley, and R. E. Lopez, 1986: Results of seeding for dynamic effect on rain-cell properties in FACE-2. J. Climate Appl. Meteor., 25, 3–13, doi:10.1175/1520-0450(1986)025<0003:ROSFDE>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Geerts, B., Q. Miao, Y. Yang, R. Rasmussen, and D. Breed, 2010: An airborne profiling radar study of the impact of glaciogenic cloud seeding on snowfall from winter orographic clouds. J. Atmos. Sci., 67, 3286–3301, doi:10.1175/2010JAS3496.1.

    • Search Google Scholar
    • Export Citation

  • Geerts, B., Q. Miao, and Y. Yang, 2011: Boundary-layer turbulence and orographic precipitation growth in cold clouds: Evidence from profiling airborne radar data. J. Atmos. Sci., 68, 2344–2365, doi:10.1175/JAS-D-10-05009.1.

    • Search Google Scholar
    • Export Citation

  • Geerts, B., and Coauthors, 2013: The AgI Seeding Cloud Impact Investigation (ASCII) campaign 2012: Overview and preliminary results. J. Wea. Modif., 45, 24–43.

    • Search Google Scholar
    • Export Citation

  • Geerts, B., Y. Yang, R. Rasmussen, S. Haimov, and B. Pokharel, 2015: Snow growth and transport patterns in orographic storms as estimated from airborne vertical-plane dual-Doppler radar data. Mon. Wea. Rev., 143, 644–665, doi:10.1175/MWR-D-14-00199.1.

    • Search Google Scholar
    • Export Citation

  • Gourley, J. J., P. Tabary, and J. P. D. Chatelet, 2007: A fuzzy logic algorithm for the separation of precipitating from nonprecipitating echoes using polarimetric radar observations. J. Atmos. Oceanic Technol., 24, 1439–1451, doi:10.1175/JTECH2035.1.

    • Search Google Scholar
    • Export Citation

  • Grant, L. O., and R. E. Elliott, 1974: The cloud seeding temperature window. J. Appl. Meteor., 13, 355–363, doi:10.1175/1520-0450(1974)013<0355:TCSTW>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Hobbs, P. V., J. H. Lyons, J. D. Locatelli, K. R. Biswas, L. F. Radke, R. R. Weiss, and A. L. Rangno, 1981: Radar detection of cloud-seeding effects. Science, 213, 1250–1252, doi:10.1126/science.213.4513.1250.

    • Search Google Scholar
    • Export Citation

  • Holroyd, E. W., J. T. McPartland, and A. B. Super, 1988: Observation of silver iodide plumes over the Grand Mesa of Colorado. J. Appl. Meteor., 27, 1125–1144, doi:10.1175/1520-0450(1988)027<1125:OOSIPO>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Holroyd, E. W., J. A. Heimbach, and A. B. Super, 1995: Observations and model simulation of AgI seeding within a winter storm over Utah’s Wasatch Plateau. J. Wea. Modif., 27, 35–56.

    • Search Google Scholar
    • Export Citation

  • Houze, R. A., Jr., 1993: Cloud Dynamics.Academic Press, 573 pp.

  • Huggins, A. W., 1995: Mobile microwave radiometer observations: Spatial characteristics of supercooled cloud water and cloud seeding implications. J. Appl. Meteor., 34, 432–446, doi:10.1175/1520-0450-34.2.432.

    • Search Google Scholar
    • Export Citation

  • Huggins, A. W., 2007: Another wintertime cloud seeding case study with strong evidence of seeding effects. J. Wea. Modif., 39, 9–36.

  • Jing, X., and B. Geerts, 2015: Dual-polarization radar data analysis of the impact of ground-based glaciogenic seeding on winter orographic clouds. Part II: Convective clouds. J. Appl. Meteor. Climatol., doi:10.1175/JAMC-D-15-0056.1, in press.

    • Search Google Scholar
    • Export Citation

  • Kucera, P. A., A. Theisen, and D. Langerud, 2008: Polarimetric Cloud Analysis and Seeding Test (POLCAST). J. Wea. Modif., 40, 64–76.

  • Langmuir, I., 1950: Control of precipitation from cumulus clouds by various seeding techniques. Science, 112, 35–41, doi:10.1126/science.112.2898.35.

    • Search Google Scholar
    • Export Citation

  • Lee, C. K., G. W. Lee, I. Zawadzki, and K.-E. Kim, 2009: A preliminary analysis of spatial variability of raindrop size distributions during stratiform rain events. J. Appl. Meteor. Climatol., 48, 270–283, doi:10.1175/2008JAMC1877.1.

    • Search Google Scholar
    • Export Citation

  • Manton, M. J., and L. Warren, 2011: A confirmatory snowfall enhancement project in the Snowy Mountains of Australia. Part II: Primary and associated analyses. J. Appl. Meteor. Climatol., 50, 1448–1458, doi:10.1175/2011JAMC2660.1.

    • Search Google Scholar
    • Export Citation

  • Markowski, P., and Y. Richardson, 2010: Mesoscale Meteorology in Midlatitudes. Wiley-Blackwell, 407 pp.

  • Matrosov, S. Y., C. Campbell, D. Kingsmill, and E. Sukovich, 2009: Assessing snowfall rates from X-band radar reflectivity measurements. J. Atmos. Oceanic Technol., 26, 2324–2339, doi:10.1175/2009JTECHA1238.1.

    • Search Google Scholar
    • Export Citation

  • Miao, Q., and B. Geerts, 2013: Airborne measurements of the impact of ground-based glaciogenic cloud seeding on orographic precipitation. Adv. Atmos. Sci., 30, 1025–1038, doi:10.1007/s00376-012-2128-2.

    • Search Google Scholar
    • Export Citation

  • Morrison, A. E., S. T. Siems, and M. J. Manton, 2013: On a natural environment for glaciogenic cloud seeding. J. Appl. Meteor. Climatol., 52, 1097–1104, doi:10.1175/JAMC-D-12-0108.1.

    • Search Google Scholar
    • Export Citation

  • National Research Council, 2003: Critical Issues in Weather Modification Research. National Academies Press, 123 pp.

  • Oye, R., C. Mueller, and S. Smith, 1995: Software for radar translation, visualization, editing, and interpolation. Preprints, 27th Conf. on Radar Meteorology, Vail, CO, Amer. Meteor. Soc., 359–361.

  • Plummer, D. M., S. Göke, R. M. Rauber, and L. D. Girolamo, 2010: Discrimination of mixed- versus ice-phase clouds using dual-polarization radar with application to detection of aircraft icing regions. J. Appl. Meteor. Climatol., 49, 920–936, doi:10.1175/2009JAMC2267.1.

    • Search Google Scholar
    • Export Citation

  • Pokharel, B., B. Geerts, and X. Jing, 2014a: The impact of ground-based glaciogenic seeding on orographic clouds and precipitation: A multi-sensor case study. J. Appl. Meteor. Climatol., 53, 890–909, doi:10.1175/JAMC-D-13-0290.1.

    • Search Google Scholar
    • Export Citation

  • Pokharel, B., and Coauthors, 2014b: The impact of ground-based glaciogenic seeding on clouds and precipitation over mountains: A multi-sensor case study of shallow precipitating orographic cumuli. Atmos. Res., 147–148, 162–182, doi:10.1016/j.atmosres.2014.05.014.

    • Search Google Scholar
    • Export Citation

  • Que, M., M. Galletti, J. Verlinde, and E. E. Clothiaux, 2013: Ice crystals in Arctic mixed-phase clouds observed by an X-band polarimetric radar. Presentation, 2013 ASR Fall Working Groups Meeting, Rockville, MD, U.S. Dept. of Energy Atmospheric System Research, 23 pp. [Available online at http://asr.science.energy.gov/meetings/fall-working-groups/2013/presentations/oue.pdf.]

  • Ritzman, J. M., 2013: Estimates of the fraction of precipitation seedable under application of the Wyoming Weather Modification Pilot Project seeding criteria. M.S. thesis, Dept. of Atmospheric Science, University of Wyoming, 96 pp.

  • Rosenfeld, D., and W. L. Woodley, 1989: Effects of cloud seeding in west Texas. J. Appl. Meteor., 28, 1050–1080, doi:10.1175/1520-0450(1989)028<1050:EOCSIW>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Rutledge, S. A., and P. V. Hobbs, 1983: The mesoscale and microscale structure and organization of clouds and precipitation in midlatitude cyclones. VIII: A model for the “seeder-feeder” process in warm-frontal rainbands. J. Atmos. Sci., 40, 1185–1206, doi:10.1175/1520-0469(1983)040<1185:TMAMSA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Silverman, B. A., 2001: A critical assessment of glaciogenic seeding of convective clouds for rainfall enhancement. Bull. Amer. Meteor. Soc., 82, 903–921, doi:10.1175/1520-0477(2001)082<0903:ACAOGS>2.3.CO;2.

    • Search Google Scholar
    • Export Citation

  • Simpson, J., and W. L. Woodley, 1971: Seeding cumulus in Florida: New 1970 results. Science, 172, 117–126, doi:10.1126/science.172.3979.117.

    • Search Google Scholar
    • Export Citation

  • Smith, E. J., 1949: Experiments in seeding cumuliform cloud layers with dry ice. Aust. J. Sci. Res., 2, 78–91.

  • Super, A. B., 1974: Silver iodide plume characteristics over the Bridger Mountain Range, Montana. J. Appl. Meteor., 13, 62–70, doi:10.1175/1520-0450(1974)013<0062:SIPCOT>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Super, A. B., 1999: Summary of the NOAA/Utah Atmospheric Modification Program: 1990-1998. J. Wea. Modif., 31, 51–75.

  • Super, A. B., and B. A. Boe, 1988: Microphysical effects of wintertime cloud seeding with silver iodide over the Rocky Mountains. Part III: Observations over the Grand Mesa, Colorado. J. Appl. Meteor., 27, 1166–1182, doi:10.1175/1520-0450(1988)027<1166:MEOWCS>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Super, A. B., and J. A. Heimbach, 1988: Microphysical effects of wintertime cloud seeding with silver iodide over the Rocky Mountains. Part II: Observations over the Bridger Range, Montana. J. Appl. Meteor., 27, 1152–1165, doi:10.1175/1520-0450(1988)027<1152:MEOWCS>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Thompson, E. J., S. A. Rutledge, B. Dolan, V. Chandrasekar, and B. L. Cheong, 2014: A dual-polarization radar hydrometeor classification algorithm for winter precipitation. J. Atmos. Oceanic Technol., 31, 1457–1481, doi:10.1175/JTECH-D-13-00119.1.

    • Search Google Scholar
    • Export Citation

  • Vali, G., D. Leon, and J. R. Snider, 2012: Ground-layer snow clouds. Quart. J. Roy. Meteor. Soc., 138, 1507–1525, doi:10.1002/qj.1882.

    • Search Google Scholar
    • Export Citation

  • Vivekanandan, J., V. N. Bringi, M. Hagen, and P. Meischner, 1994: Polarimetric radar studies of atmospheric ice particles. IEEE Trans. Geosci. Remote Sens., 32, 1–10, doi:10.1109/36.285183.

    • Search Google Scholar
    • Export Citation

  • Vivekanandan, J., S. M. Ellis, R. Oye, D. S. Zrnic, A. V. Ryzhkov, and J. Straka, 1999: Cloud microphysics retrieval using S-band dual-polarization radar measurements. Bull. Amer. Meteor. Soc., 80, 381–388, doi:10.1175/1520-0477(1999)080<0381:CMRUSB>2.0.CO;2.

    • Search Google Scholar
    • Export Citation

  • Vonnegut, B., and H. Chessin, 1971: Ice nucleation by coprecipitated silver iodide and silver bromide. Science, 174, 945–946, doi:10.1126/science.174.4012.945.

    • Search Google Scholar
    • Export Citation

  • Xue, L., and Coauthors, 2013a: AgI cloud seeding effects as seen in WRF simulations. Part I: Model description and idealized 2D sensitivity tests. J. Appl. Meteor. Climatol., 52, 1433–1457, doi:10.1175/JAMC-D-12-0148.1.

    • Search Google Scholar
    • Export Citation

  • Xue, L., S. Tessendorf, E. Nelson, R. Rasmussen, D. Breed, S. Parkinson, P. Holbrook, and D. Blestrud, 2013b: AgI cloud seeding effects as seen in WRF simulations. Part II: 3D real case simulations and sensitivity tests. J. Appl. Meteor. Climatol., 52, 1458–1476, doi:10.1175/JAMC-D-12-0149.1.

    • Search Google Scholar
    • Export Citation

  • Xue, L., X. Chu, R. Rasmussen, D. Breed, B. Boe, and B. Geerts, 2014: The dispersion of silver iodide particles from ground-based generators over complex terrain. Part II: WRF large-eddy simulations versus observations. J. Appl. Meteor. Climatol., 53, 1342–1361, doi:10.1175/JAMC-D-13-0241.1.

    • Search Google Scholar
    • Export Citation

  • Xue, L., X. Chu, R. Rasmussen, D. Breed, and B. Geerts, 2015: A case study of radar observations and WRF LES simulations of the impact of ground-based glaciogenic seeding on orographic clouds and precipitation. Part II: AgI dispersion and seeding signals simulated by WRF. J. Appl. Meteor. Climatol., submitted.

    • Search Google Scholar
    • Export Citation

  • Yuter, S. E., and R. A. Houze Jr., 1995: Three-dimensional kinematic and microphysical evolution of Florida cumulonimbus. Part II: Frequency distributions of vertical velocity, reflectivity, and differential reflectivity. Mon. Wea. Rev., 123, 1941–1963, doi:10.1175/1520-0493(1995)123<1941:TDKAME>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 610 295 6
PDF Downloads 205 76 17