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An Observation Operator for Radar Refractivity Change: Comparison of Observations and Convective-Scale Simulations

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Abstract

Weather radar refractivity depends on low-level moisture, temperature, and pressure and is available at high space–time resolutions over large areas. It is of definite meteorological interest for assimilation, verification, and process-study purposes. In this study, the path-averaged refractivity change is simulated from the Arome cloud-resolving atmospheric system analyses and compared with corresponding radar observations over a 35-day period with various meteorological conditions. For that, a novel post-processing procedure is applied to radar data to improve its quality. Also, an observation operator is developed that ingests Arome analyses and simulates a 3-h path-averaged refractivity change. A sensitivity study shows that simulated path-averaged refractivity change is immune to the modelling of the beam height as long as it remains below approximately 60 m above the ground. Comparisons show overall consistency between observed and simulated path-averaged refractivity change, with discrepancies at times that suggest an improvement in analyses once radar refractivity change observations are assimilated. Finally, errors introduced when retrieving local refractivity from path-averaged refractivity are estimated and it is found for our dataset that such retrievals halve the range of usable observations.

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Notes

  1. HYdrological cycle in the Mediterranean Experiment (HyMeX, http://www.hymex.org/) is an international experimental programme that aims to improve our understanding of the water cycle in the Mediterranean area.

References

  • Bénard P, Vivoda J, Mašek J, Smolíková P, Yessad K, Smith C, Brožková R, Geleyn JF (2010) Dynamical kernel of the Aladin-NH spectral limited-area model: revised formulation and sensitivity experiments. Q J R Meteorol Soc 136(646):155–169. doi:10.1002/qj.522

    Article  Google Scholar 

  • Besson L, Boudjabi C, Caumont O (2012) Links between weather phenomena and characteristics of refractivity measured by precipitation radar. Boundary-Layer Meteorol 143(1):77–95. doi:10.1007/s10546-011-9656-7

    Article  Google Scholar 

  • Bodine D, Heinselman PL, Cheong BL, Palmer RD, Michaud D (2010) A case study on the impact of moisture variability on convection initiation using radar refractivity retrievals. J Appl Meteorol Climatol 49(8):1766–1778. doi:10.1175/2010JAMC2360.1

    Article  Google Scholar 

  • Bodine D, Michaud D, Palmer RD, Heinselman PL, Brotzge J, Gasperoni N, Cheong BL, Xue M, Gao J (2011) Understanding radar refractivity: sources of uncertainty. J Appl Meteorol Climatol 50(12):2543–2560. doi:10.1175/2011JAMC2648.1

    Article  Google Scholar 

  • Boniface K, Ducrocq V, Jaubert G, Yan X, Brousseau P, Masson F, Champollion C, Chéry J, Doerflinger E (2009) Impact of high-resolution data assimilation of GPS zenith delay on Mediterranean heavy rainfall forecasting. Ann Geophys 27:2739–2753. http://www.ann-geophys.net/27/2739/2009/

    Google Scholar 

  • Brousseau P, Berre L, Bouttier F, Desroziers G (2011) Background-error covariances for a convective-scale data-assimilation system: AROME-France 3D-Var. Q J R Meteorol Soc 137(655):409–422. doi:10.1002/qj.750

    Article  Google Scholar 

  • Caumont O, Ducrocq V, Wattrelot É, Jaubert G, Pradier-Vabre S (2010) 1D+3DVar assimilation of radar reflectivity data: a proof of concept. Tellus 62A(2):173–187. doi:10.1111/j.1600-0870.2009.00430.x

    Google Scholar 

  • Courtier P, Thépaut JN, Hollingsworth A (1994) A strategy for operational implementation of 4D-Var using an incremental approach. Q J R Meteorol Soc 120:1367–1388

    Article  Google Scholar 

  • Demoz B, Flamant C, Weckwerth T, Whiteman D, Evans K, Fabry F, Di Girolamo P, Miller D, Geerts B, Brown W, Schwemmer G, Gentry B, Feltz W, Wang Z (2006) The dryline on 22 May 2002 during \(\text{ IHOP }\_\)2002: convective-scale measurements at the profiling site. Mon Weather Rev 134(1):294–310. doi:10.1175/MWR3054.1

    Google Scholar 

  • Fabry F (2004) Meteorological value of ground target measurements by radar. J Atmos Ocean Technol 21(4):560–573. doi:10.1175/1520-0426(2004)021<0560:MVOGTM>2.0.CO;2

    Google Scholar 

  • Fabry F (2006) The spatial variability of moisture in the boundary layer and its effect on convection initiation: project-long characterization. Mon Weather Rev 134(1):79–91. doi:10.1175/MWR3055.1

    Article  Google Scholar 

  • Fabry F, Frush C, Zawadzki I, Kilambi A (1997) On the extraction of near-surface index of refraction using radar phase measurements from ground targets. J Atmos Ocean Technol 14(4):978–987. doi:10.1175/1520-0426(1997)014<0978:OTEONS>2.0.CO;2

  • Figueras i Ventura J, Boumahmoud AA, Fradon B, Dupuy P, Tabary P (2012) Long-term monitoring of French polarimetric radar data quality and evaluation of several polarimetric quantitative precipitation estimators in ideal conditions for operational implementation at C-band. Q J R Meteorol Soc 138(669):2212–2228. doi:10.1002/qj.1934

    Article  Google Scholar 

  • Fischer C, Montmerle T, Berre L, Auger L, Ştefănescu SE (2005) An overview of the variational assimilation in the ALADIN/France numerical weather-prediction system. Q J R Meteorol Soc 131(613):3477–3492. doi:10.1256/qj.05.115

    Article  Google Scholar 

  • Lafore JP, Stein J, Asencio N, Bougeault P, Ducrocq V, Duron J, Fischer C, Héreil P, Mascart P, Masson V, Pinty JP, Redelsperger JL, Richard É, Vilà-Guerau de Arellano J (1998) The meso-NH atmospheric simulation system. Part I: Adiabatic formulation and control simulations. Scientific objectives and experimental design. Ann Geophys 16(1):90–109

    Google Scholar 

  • Masson V, Seity Y (2009) Including atmospheric layers in vegetation and urban offline surface schemes. J Appl Meteorol Climatol 48(7):1377–1397. doi:10.1175/2009JAMC1866.1

    Article  Google Scholar 

  • Montmerle T, Faccani C (2009) Mesoscale assimilation of radial velocities from Doppler radar in a pre-operational framework. Mon Weather Rev 137(6):1939–1953. doi:10.1175/2008MWR2725.1

    Article  Google Scholar 

  • Montmerle T, Caya A, Zawadzki I (2002) Short-term numerical forecasting of a shallow storms complex using bistatic and single-doppler radar data. Weather Forecast 17(6):1211–1225. doi:10.1175/1520-0434(2002)017<1211:STNFOA>2.0.CO;2

  • Parent du Châtelet J, Boudjabi C, Besson L, Caumont O (2012) Errors caused by long-term drifts of magnetron frequencies for refractivity measurement with a radar: theoretical formulation and initial validation. J Atmos Ocean Technol 29(10):1428–1434. doi:10.1175/JTECH-D-12-00070.1

    Article  Google Scholar 

  • Park S, Fabry F (2010) Simulation and interpretation of the phase data used by the radar refractivity retrieval algorithm. J Atmos Ocean Technol 27(8):1286–1301. doi:10.1175/2010JTECHA1393.1

    Article  Google Scholar 

  • Schelleng JC, Burrows CR, Ferrell EB (1933) Ultra-short-wave propagation. Proc IRE 21(3):427–463

    Article  Google Scholar 

  • Seity Y, Brousseau P, Malardel S, Hello G, Bénard P, Bouttier F, Lac C, Masson V (2011) The AROME-France convective-scale operational model. Mon Weather Rev 139(3):976–991. doi:10.1175/2010MWR3425.1

    Article  Google Scholar 

  • Smith EK Jr, Weintraub S (1953) The constants in the equation for atmospheric refractive index at radio frequencies. Proc IRE 41:1035–1037

    Article  Google Scholar 

  • Sun J (2005) Convective-scale assimilation of radar data: progress and challenges. Q J R Meteorol Soc 131(613):3439–3463. doi:10.1256/qj.05.149

    Article  Google Scholar 

  • Weckwerth TM, Pettet CR, Fabry F, Park SJ, LeMone MA, Wilson JW (2005) Radar refractivity retrieval: validation and application to short-term forecasting. J Appl Meteorol 44(3):285–300. doi:10.1175/JAM-2204.1

    Google Scholar 

  • Yan X, Ducrocq V, Jaubert G, Brousseau P, Poli P, Champollion C, Flamant C, Boniface K (2009) The benefit of GPS zenith delay assimilation to high-resolution quantitative precipitation forecasts: a case-study from COPS IOP 9. Q J R Meteorol Soc 135(644):1788–1800. doi:10.1002/qj.508

    Article  Google Scholar 

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Acknowledgments

The authors and their organizations thank the European Union, the Provence-Alpes-Côte d’Azur Region and the French Ministry of Ecology, Sustainable Development, Transport and Housing for co-financing the Rhytmme project. This study also benefited from support from the French National Research Programme LEFE of the National Institute for Universe Sciences (INSU) through the Antydote project. This work is a contribution to the HyMeX programme through the Ioda-Med project funded by the French National Research Agency (ANR). Two anonymous reviewers provided reviews that led to significant improvements to this manuscript.

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Authors and Affiliations

  1. CNRM-GAME (Météo-France, CNRS), 42 av G. Coriolis, 31057 , Toulouse Cedex 01, France

    Olivier Caumont

  2. French National Hydrometeorological and Flood Forecasting Centre (SCHAPI), 42 av G. Coriolis, 31057 , Toulouse Cedex 01, France

    Anouck Foray

  3. DSO/CMI (Météo-France) and Latmos, 4 Place Jussieu, 75005 , Paris, France

    Lucas Besson

  4. DSO/CMI (Météo-France) and Latmos, 11 bd D’Alembert, 78280 , Guyancourt, France

    Jacques Parent du Châtelet

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  1. Olivier Caumont
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  2. Anouck Foray
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  3. Lucas Besson
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  4. Jacques Parent du Châtelet
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Correspondence to Olivier Caumont.

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Caumont, O., Foray, A., Besson, L. et al. An Observation Operator for Radar Refractivity Change: Comparison of Observations and Convective-Scale Simulations. Boundary-Layer Meteorol 148, 379–397 (2013). https://doi.org/10.1007/s10546-013-9820-3

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  • DOI: https://doi.org/10.1007/s10546-013-9820-3

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