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Variation of Radio Refractivity with Respect to Moisture and Temperature and Influence on Radar Ray Path

Variation of Radio Refractivity with Respect to Moisture and Temperature and Influence on Radar Ray Path
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摘要 In this study, the variation of radio refractivity with respect to temperature and moisture is analyzed. Also, the effects of vertical gradients in temperature and moisture on the propagation paths of electromagnetic waves of weather radar are examined for several sites across the United States using several years of sounding data from the National Weather Service. The ray path is important for identifying storm characteristics and for properly using the radar data in initializing numerical weather prediction models. It is found that during the warm season the radio refractivity gradient is more sensitive to moisture gradients than to temperature gradients. Ray paths from the commonly accepted vertical ray path model are compared to a ray path computed from a stepwise ray tracing algorithm using data from actual soundings. For the sample of about 16 000 soundings examined, we find that only a small fraction of the ray paths diverge significantly from those calculated using a ray path model based on the US Standard Atmosphere. While the problem of ray dueting in the presence of a temperature inversion is fairly well known, we identify the presence of a strong vertical moisture gradient as the culprit in the majority of the cases where significant deviations occurred. In this study, the variation of radio refractivity with respect to temperature and moisture is analyzed. Also, the effects of vertical gradients in temperature and moisture on the propagation paths of electromagnetic waves of weather radar are examined for several sites across the United States using several years of sounding data from the National Weather Service. The ray path is important for identifying storm characteristics and for properly using the radar data in initializing numerical weather prediction models. It is found that during the warm season the radio refractivity gradient is more sensitive to moisture gradients than to temperature gradients. Ray paths from the commonly accepted vertical ray path model are compared to a ray path computed from a stepwise ray tracing algorithm using data from actual soundings. For the sample of about 16 000 soundings examined, we find that only a small fraction of the ray paths diverge significantly from those calculated using a ray path model based on the US Standard Atmosphere. While the problem of ray dueting in the presence of a temperature inversion is fairly well known, we identify the presence of a strong vertical moisture gradient as the culprit in the majority of the cases where significant deviations occurred.
出处 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第6期1098-1106,共9页 大气科学进展(英文版)
基金 U. S. NSF Grant Nos. ATM-0331756, ATM-0331594, ATM-0530814 and EEC-0313747, and by DOT-FAA Grant NA17RJ1227-01 the National Natural Science Foun- dation of China under Grant Nos. 40620120437 and 40505022
关键词 radio refractivity radar ray path radio refractivity, radar ray path
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  • 1Alberty,R.L.,T.D.Crum,and F.Toepfer,1991:TheNEXRAD program:Past,present,and future-A 1991 perspective.Preprints,25th Int.Conf.on Radar Meteorology,Paris,Amer.Meteor.Soc.,1-8.
  • 2Bean,B.R.,and E.J.Dutton,1968:Radio Meteorology.Dover Publications,435pp.
  • 3Brewster,K.A.,2003:Phase-correcting data assimilation and application to storm scale numerical weather prediction.Part Ⅱ:Application to a severe storm outbreak.Mon.Wea.Rev.,131,493-507.
  • 4Bluestein,H.B.,1993:Synoptic-Dynamic Meteorology in Midlatitudes.Volume Ⅱ,Oxford University Press,Inc,594pp.
  • 5Crook,N.A.,and J.Sun,2002:Assimilating radar,surface,and profiler data for the Sydney 2000 Forecast Demonstration Project.J.Atmos.Oceanic Technol.,19,888-898.
  • 6Crum,T.D.,R.E.Saffle,and J.W.Wilson,1998:An update on the NEXRAD Program and future WSR-88D support to operations.Wea.Forecasting,13,253-262.
  • 7Doviak,R.J.,and D.S.Zrnic,1993:Doppler Radar and Weather Observations.Academic Press,2nd ed.,562pp.
  • 8Droegemeier,K.K.,1990:Toward a science of stormscale prediction.Preprint,16th Conf.on Severe Local Storms,Kananaskis Park,Alberta,Canada,Amer.Meteor.Soc.,256-262.
  • 9Droegemeier,K.K.,1997:The numerical prediction of thunderstorms:Challenges,potential benefits,and results from real time operational tests.WMO Bulletin,46,324-336.
  • 10Gao,J.,M.Xue,Z.Wang,and K.K.Droegemeier,1998:The initial condition and explicit prediction of convection using ARPS forward assimilation and adjoint methods with WSR-88D data.Preprints,12th Conference on Numerical Weather Prediction,Phoenix,AZ,Amer.Meteor.Soc.,176-178.

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