polarimetric radar

2010-01-01 〜2011-03-01

 

Showing: 1 - 20 of 32

 

Operational Monitoring of Radar Differential Reflectivity Using the Sun

Iwan Holleman, Asko Huuskonen, Rashpal Gill, Pierre Tabary

Journal of Atmospheric and Oceanic Technology

Volume 27, Issue 5 (May 2010) pp. 881-887

doi: 10.1175/2010JTECHA1381.1Abstract

A method for the daily monitoring of the differential reflectivity bias for polarimetric weather radars is presented. Sun signals detected in polar volume data produced during operational scanning of the radar are used. This method is an ...

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太陽の信号で鉛直偏波と水平偏波のバイアス補正をおこなう手法を提案する。偏波のバイアスをなくすことは、定量観測に重要なので、降雨時に天頂に振る観測とともに、太陽による補正も現業に組み込むことが望まれる。オンラインの太陽観測と降雨の天頂観測による補正で、出力の偏波バイアスと受信の偏波バイアスを切り分けることができる。

【太陽がどのように見えるかは不明】3/211 1003.htm

 

Rapid-Scan Super-Resolution Observations of a Cyclic Supercell with a Dual-Polarization WSR-88D

Matthew R. Kumjian, Alexander V. Ryzhkov, Valery M. Melnikov, Terry J. Schuur

Monthly Weather Review

Volume 138, Issue 10 (October 2010) pp. 3762-3786

doi: 10.1175/2010MWR3322.1

Abstract

In recent years, there has been widespread interest in collecting and analyzing rapid updates of radar data in severe convective storms. To this end, conventional single-polarization rapid-scan radars and phased array radar systems have been ...

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近年レーダが発達し、対流性の降雨データが短期間に更新される。単一偏波のレーダデータを短期間で解析する手法は、検討が進んでいるが、2重偏波についてはまだ検討が十分でない。

2重偏波の解析スキームをフェイズドアレー型のレーダと組み合わせて提案する。

熱帯性ではないスーパセルの解析例を同時に示す。下層に振動が見られた。3/211

 

Analysis of ZR Relations Based on LDR Signatures within the Melting Layer

Stefan Kowalewski, Gerhard Peters

Journal of Atmospheric and Oceanic Technology

Volume 27, Issue 9 (September 2010) pp. 1555-1561

doi: 10.1175/2010JTECHA1363.1

Abstract

The inclusion of polarimetric measurements for the quantitative precipitation estimation (QPE) by weather radars as well as space- and airborne radars is considered most promising now-a-days. Because the melting layer region is usually marked by ...

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1011 3章まで3/311

 

Polarimetric Attenuation Correction in Heavy Rain at C Band

Ji-Young Gu, A. Ryzhkov, P. Zhang, P. Neilley, M. Knight, B. Wolf, Dong-In Lee

Journal of Applied Meteorology and Climatology

Volume 50, Issue 1 (January 2011) pp. 39-58

doi: 10.1175/2010JAMC2258.1

Abstract

The ability of C-band polarimetric radar to account for strong attenuation/differential attenuation is demonstrated in two cases of heavy rain that occurred in the Chicago, Illinois, metropolitan area on 5 August 2008 and in central Oklahoma on ...

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C帯の偏波を用いた減衰補正の性能を示す。対象は、イリノイ州シカゴとオクラホマの2事例。強い降雨によって局所的に大きな減衰が発生するところと広範囲に雨があることで減衰するところについての減衰補正の性能を確認した。減衰量が40Bもあれば、減衰補正はかなり正確におこなえる。オクラホマではS帯のレーダと比較して精度を確認した。3/711

 

Prospects of the WSR-88D radar for cloud studies

Valery M. Melnikov, Dusan S. Zrnic, Richard J. Doviak, Phillip B. Chilson, David B. Mechem, Yefim L. Kogan

Journal of Applied Meteorology and Climatology

Volume 0, Issue 0 ( ) pp.

doi: 10.1175/2010JAMC2303.1

Abstract

Sounding of nonprecipitating clouds with the10-cm wavelength WSR-88D weather radar is discussed. Readily available enhancements to signal processing and volume coverage patterns of the WSR-88D allow observations of a variety of clouds with ...

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波長10cmWSR88Dで非降水雲の観測例を示す。信号処理を強化したので10km遠方でー25dBZまでの信号は観測できる。50kmレンジ内の、雲の反射強度因子、ドップラ速度、スペクトル幅について議論した。

WSR88Dのネットワークでリアルタイムの情報が収集できる。氷雲、水雲の遷移状態も3次元で観測できる。水雲の場合はZDRZに相関があるが、氷雲の場合はZDRが大きく、Zと相関がない。雲の内部で雨が観測されるかなり上空でZDR8dBを超えるような値が観測される。

WSR88D157の偏波レーダがネットワークを構成している。気候の研究にも役立つ3/811

 

Polarimetric radar observation operator for a cloud model with spectral microphysics

A. Ryzhkov, M. Pinsky, A. Pokrovsky, A. Khain

Journal of Applied Meteorology and Climatology

Volume 0, Issue 0 ( ) pp.

Abstract

Radar observation operator for computation of polarimetric radar variables from the output of numerical cloud models is described in its most generic form. This operator is combined with the Hebrew University of Jerusalem cloud model with ...

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スペクトル情報を活用する雲モデルで偏波パラメータを計算した。オクラホマのSCの観測事例と比較した。モデルと観測の比較について報告する。○3/911

 

Polarimetric Phased Array Radar for Weather Measurement: A Planar or Cylindrical Configuration?

Guifu Zhang, Richard J. Doviak, Dusan S. Zrnic, Robert Palmer, Lei Lei, Yasser Al-Rashid

Journal of Atmospheric and Oceanic Technology

Volume 0, Issue 0 ( ) pp.

doi: 10.1175/2010JTECHA1470.1

Abstract

This paper suggests a cylindrical configuration for agile beam Polarimetric Phased Array Radar (PPAR) for weather surveillance. The mostly used array configuration for PAR is a planar array antenna. The planar configuration, however, has ...

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フェイズドアレー型のドップラーレーダ雨量計(早いビーム走査が必要)でビームを平面にするか、円柱にするかで観測値を考察。円柱にしたほうが偏波観測には有利であった。×3/911

 

Precipitation Measurement at CESAR, the Netherlands

H. Leijnse, R. Uijlenhoet, C. Z. van de Beek, A. Overeem, T. Otto, C. M. H. Unal, Y. Dufournet, H. W. J. Russchenberg, J. Figueras i Ventura, H. Klein Baltink, I. Holleman

Journal of Hydrometeorology

Volume 11, Issue 6 (December 2010) pp. 1322-1329

doi: 10.1175/2010JHM1245.1

Abstract

The Cabauw Experimental Site for Atmospheric Research (CESAR) observatory hosts a unique collection of instruments related to precipitation measurement. The data collected by these instruments are stored in a database that is freely accessible ...

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1010

 

Using CASA IP1 to Diagnose Kinematic and Microphysical Interactions in a Convective Storm

Brenda Dolan, Steven A. Rutledge

Monthly Weather Review

Volume 138, Issue 5 (May 2010) pp. 1613-1634

doi: 10.1175/2009MWR3016.1

Abstract

Data from the Collaborative Adaptive Sensing of the Atmosphere (CASA) Integrated Project I (IP1) network of polarimetric X-band radars are used to observe a convective storm. A fuzzy logic hydrometeor identification algorithm is employed to study ...

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大気探査機器の集合計画(CASA)X帯レーダのネットワークで対流雲を観測した。雲物理過程を調査するため、ファジーで粒子判別をおこなった。比較としてNEXRADKOUNS帯偏波レーダ)を用いた。雲の発達の指標として発雷のデータを解析した。

解析に今回開発した上空の鉛直風を推定する手法を用いている。上昇流の発達・霰の成長・発雷、下降流の開始・霰の落下がXバンドレーダで良く捉えられている。上空はレンジの限界(KOUNより低い)で中層・下層で上層のエラーを緩和してもデュアルの風の場の精度が落ちる。しかし中層・下層の観測範囲はKOUNよりもよい。○3/1011

 

Polarimetric and Electrical Characteristics of a Lightning Ring in a Supercell Storm

Clark D. Payne, Terry J. Schuur, Donald R. MacGorman, Michael I. Biggerstaff, Kristin M. Kuhlman, W. David Rust

Monthly Weather Review

Volume 138, Issue 6 (June 2010) pp. 2405-2425

doi: 10.1175/2009MWR3210.1

Abstract

On 30 May 2004, a supercell storm was sampled by a suite of instrumentation that had been deployed as part of the Thunderstorm Electrification and Lightning Experiment (TELEX). The instrumentation included the Oklahoma Lightning Mapping Array (OK-...

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1007同じ事例の論文あり

2004530日、TELEX期間にスーパセルが発達した。WSR88D2台の移動型C帯レーダを組合せ、スーパセルの力学、微物理、電気場を調べた。発雷がリング状に発達した事例に注目する。上昇流は0012UTCに始まり0039UTに活発になり、0050UTCに崩壊した。発雷の密度を調べた3/1111

 

 

Quality Control and Calibration of the Dual-Polarization Radar at Kwajalein, RMI

David A. Marks, David B. Wolff, Lawrence D. Carey, Ali Tokay

Journal of Atmospheric and Oceanic Technology

Volume 0, Issue 0 ( ) pp.

doi: 10.1175/2010JTECHA1462.1

Abstract

The dual-polarization weather radar on Kwajalein Atoll in the Republic of the Marshall Islands (KPOL) is one of the only full-time (24/7) operational S-band dual-polarimetric (DP) radars in the tropics. Through the use of KPOL DP and disdrometer ...

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マーシャル島共和国の二重偏波レーダ(KPOL)は熱帯での唯一のS帯偏波(DP)レーダである。このレーダを用いて品質管理の技術を開発した。鉛直観測がおこなえないときに偏波を補正するアルゴリズムを提案する。

以下の結果を示す。

1)偏波の品質管理をTRMMの品質管理と比べる

2)反射強度因子の校正を偏波情報を積分して、弱い雨について実施した。

ここの雨については1dB以内で一致が見られた。この技術はWSR88Dに取り入れられPMMに恩恵をもたらすだろう3/1611.

 

 

The Impact of Evaporation on Polarimetric Characteristics of Rain: Theoretical Model and Practical Implications

Matthew R. Kumjian, Alexander V. Ryzhkov

Journal of Applied Meteorology and Climatology

Volume 49, Issue 6 (June 2010) pp. 1247-1267

doi: 10.1175/2010JAMC2243.1

Abstract

Soon, the National Weather Service’s Weather Surveillance Radar-1988 Doppler (WSR-88D) network will be upgraded to allow dual-polarization capabilities. Therefore, it is imperative to understand and identify microphysical processes using the ...

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1003 WSR-88D

 

Simulations of Polarimetric Radar Signatures of a Supercell Storm Using a Two-Moment Bulk Microphysics Scheme

Youngsun Jung, Ming Xue, Guifu Zhang

Journal of Applied Meteorology and Climatology

Volume 49, Issue 1 (January 2010) pp. 146-163

doi: 10.1175/2009JAMC2178.1

Abstract

A new general polarimetric radar simulator for nonhydrostatic numerical weather prediction (NWP) models has been developed based on rigorous scattering calculations using the T-matrix method for reflectivity, differential reflectivity, specific ...

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1003

 

Modeling, Error Analysis, and Evaluation of Dual-Polarization Variables Obtained from Simultaneous Horizontal and Vertical Polarization Transmit Radar. Part I: Modeling and Antenna Errors

J. C. Hubbert, S. M. Ellis, M. Dixon, G. Meymaris

Journal of Atmospheric and Oceanic Technology

Volume 27, Issue 10 (October 2010) pp. 1583-1598

doi: 10.1175/2010JTECHA1336.1

Abstract

In this two-part paper the biases of polarimetric variables from simultaneous horizontally and vertically transmitted (SHV) data are investigated. Here, in Part I, a radar-scattering model is developed and antenna polarization errors are ...

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同時発射のHVのアンテナパターンのシミュレーションによるエラー評価。part2ではNCARSpolWSR88DKOUNを対象にしている。3/20’11

 

Modeling, Error Analysis, and Evaluation of Dual-Polarization Variables Obtained from Simultaneous Horizontal and Vertical Polarization Transmit Radar. Part II: Experimental Data

J. C. Hubbert, S. M. Ellis, M. Dixon, G. Meymaris

Journal of Atmospheric and Oceanic Technology

Volume 27, Issue 10 (October 2010) pp. 1599-1607

doi: 10.1175/2010JTECHA1337.1

Abstract

In this second article in a two-part work, the biases of weather radar polarimetric variables from simultaneous horizontally and vertically transmit (SHV) data are investigated. The biases are caused by cross coupling of the simultaneously ...

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上記のpartU。KOUNのデータを用いてHVのシミュレーション(SHV)の評価。ZDRのバイアス誤差を評価した。HVの切り替えをすばやくして、SHVの評価を行ったところ、ZDRの誤差はアンテナの偏波エラーに依存するものであることがわかった。4/111

Impacts of Polarimetric Radar Observations on Hydrologic Simulation

Jonathan J. Gourley, Scott E. Giangrande, Yang Hong, Zachary L. Flamig, Terry Schuur, Jasper A. Vrugt

Journal of Hydrometeorology

Volume 11, Issue 3 (June 2010) pp. 781-796

doi: 10.1175/2010JHM1218.1

Abstract

Rainfall estimated from the polarimetric prototype of the Weather Surveillance Radar-1988 Doppler [WSR-88D (KOUN)] was evaluated using a dense Micronet rain gauge network for nine events on the Ft. Cobb research watershed in Oklahoma. The ...

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10053/25’11 偏波を用いた場合、バイアスは大きいが、ケース毎の差異は小さい。

 

Cross Validation of Space-borne Radar and Ground Polarimetric Radar Aided by Polarimetric Echo Classification of Hydrometeor Types

Yixin Wen, Yang Hong, Guifu Zhang, Terry J. Schuur, Jonathan J. Gourley, Zac Flamig, K. Robert Morris, Qing Cao

Journal of Applied Meteorology and Climatology

Volume 0, Issue 0 ( ) pp.

Abstract

Ground-based polarimetric weather radar is arguably the most powerful validation tool that provides physical insight into the development and interpretation of space-borne weather radar algorithms and observations. This study aims to compare and ...

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TRMM-PRKOUNを組み合わせて、シナジーの効果が発揮できた。4/111

 

Simultaneous Estimation of Microphysical Parameters and the Atmospheric State Using Simulated Polarimetric Radar Data and an Ensemble Kalman Filter in the Presence of an Observation Operator Error

Youngsun Jung, Ming Xue, Guifu Zhang

Monthly Weather Review

Volume 138, Issue 2 (February 2010) pp. 539-562

doi: 10.1175/2009MWR2748.1

Abstract

The impacts of polarimetric radar data on the estimation of uncertain microphysical parameters are investigated through observing system simulation experiments when the effects of uncertain parameters on the observation operators are also ...

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1003

 

Polarimetric Radar Observation of the Melting Layer in a Convective Rainfall System during the Rainy Season over the East China Sea

Yukari SHUSSE, Nobuhiro TAKAHASHI, Katsuhiro NAKAGAWA, Shinsuke SATOH, Toshio IGUCHI

Journal of Applied Meteorology and Climatology

Volume 0, Issue 0 ( ) pp.

doi: 10.1175/2010JAMC2469.1

Abstract

During the rainy season over the East China Sea, convective rainfalls often show melting layer (ML) characteristics in polarimetric radar variables. In this research, the appearance ratio of the ML (the ratio of rainfall area accompanied by ...

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1011

 

Vertical Structure of Convective Systems during NAME 2004

David G. Lerach, Steven A. Rutledge, Christopher R. Williams, Robert Cifelli

Monthly Weather Review

Volume 138, Issue 5 (May 2010) pp. 1695-1714

doi: 10.1175/2009MWR3053.1

Abstract

This study describes the vertical structure of mesoscale convective systems (MCSs) that characterized the 2004 North American monsoon utilizing observations from a 2875-MHz (S band) profiler and a dual-polarimetric scanning Doppler radar. Both ...

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1007

 

Investigation of microphysical processes occurring in isolated convection during NAME

Angela K. Rowe, Steven A. Rutledge, Timothy J. Lang

Monthly Weather Review

Volume 0, Issue 0 ( ) pp.

doi: 10.1175/2010MWR3494.1

Abstract

To address questions regarding microphysical processes occurring in the core North American monsoon region, data from NCAR's S-band, polarimetric, Doppler radar (S-Pol), deployed during the North American Monsoon Experiment (NAME) in summer 2004, ...

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NAME期間中の微物理にかかる問題を解決するため、S-POLのデータを活用した。4/411

【これまで、融解層の研究は層状の雲に限られてきた。けれども、偏波を使うことによって対流性の雲についても融解の過程が観察できるようになってきた。ここでは、孤立した対流雲の融解過程について、偏波を使って解析している】

西シラメイド山脈で発生する孤立した雲の融解状況について偏波レーダを用いて解析した。すべての高度で孤立した対流セルは、他の熱帯・中緯度の対流と同等の偏波の特徴を持つことがわかった。低い地形上の対流に着目すると降雪粒子は15km【水平?】にも広がっていることがわかった。さらに、融解層上部にはZDR【の極値?ZDRが負となるところ?】が存在し、LDRが強化されている部分が上にあった。これは、霰の形成が示唆される。西シラメイド山脈に発生する薄い対流では統計的に見て、高度の高いところで融解過程が降水の強化に重要な働きをしていた。SMO(西シラメイド山脈の頭文字)のセルでは融解高度の直上で氷水量が増加しており、粒径分布が狭いので暖かい雲の過程は制限されている。微物理の過程と雲の組織化の関連については、次の課題である。4/5’11

 

Attenuation and Differential Attenuation of 5-cm-Wavelength Radiation in Melting Hail

L. Borowska, A. Ryzhkov, D. Zrnić, C. Simmer, R. Palmer

Journal of Applied Meteorology and Climatology

Volume 50, Issue 1 (January 2011) pp. 59-76

doi: 10.1175/2010JAMC2465.1

Abstract

Presented are quantitative estimates of specific attenuation and specific differential attenuation of 5-cm-wavelength radiation (C band) obtained by comparison with measurements at 10-cm wavelength (S band), which are much less affected by ...

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C帯の減衰係数をS帯と比較して求めた。2つのレーダはオクラホマに置いた。地上観測で雹が観測されたときとされていないときで対比して減衰を計算した。簡単な1次元モデルで評価した。雹の大きさ・向き・相は形成に重要な働きをしているが、2波長の観測値を示す。4/511

 

Application of Dual-Polarization Radar Melting-Layer Detection Algorithm

S. Boodoo, D. Hudak, N. Donaldson, M. Leduc

Journal of Applied Meteorology and Climatology

Volume 49, Issue 8 (August 2010) pp. 1779-1793

doi: 10.1175/2010JAMC2421.1

Abstract

A polarimetric melting-layer detection algorithm developed for an S-band radar has been modified for use by the King City C-band radar in southern Ontario, Canada. The technique ingests radar scan volume data to determine the melting-layer top ...

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1005 4/6’11 事例解析に加えて統計解析もあり。PDF

 

A Modular Optimal Estimation Method for Combined Radar-Radiometer Precipitation Profiling

S. Joseph Munchak, Christian D. Kummerow

Journal of Applied Meteorology and Climatology

Volume 0, Issue 0 ( ) pp.

doi: 10.1175/2010JAMC2535.1

Abstract

Although zonal mean rainrates from the Tropical Rainfall Measuring Mission (TRMM) are in good (<10%) agreement between the TRMM microwave imager (TMI) and precipitation radar (PR) rainfall algorithms, significant uncertainties remain in some ...

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TRMMPRと放射計データ(TMI)は降水量について、緯度平均は一致するものの、局所的にはエラーが大きい。地上検証地点においても10%程度の誤差があるので、PRを参照して、雲水量分布をTMIから回帰的に計算する大枠(framework)を提案する。雲の粒径分布は3パラメータで近似する。積分雲水量は、PRから推定する。粒径分布と雲水量を拘束条件として降水量を求める。算定のパラメータはKwajalein(マーシャル諸島)の偏波レーダを元に調整した。TBについて観測と計算の誤差は小さくなり、DSDの気候値がもとまった。4/611

 

 

Retrieval of Three-Dimensional Raindrop Size Distribution Using X-Band Polarimetric Radar Data

D-S. Kim, M. Maki, D-I. Lee

Journal of Atmospheric and Oceanic Technology

Volume 27, Issue 8 (August 2010) pp. 1265-1285

doi: 10.1175/2010JTECHA1407.1

Abstract

An improved algorithm based on the self-consistent principle for rain attenuation correction of reflectivity ZH and differential reflectivity ZDR are presented for X-band radar. The proposed algorithm calculates the optimum coefficients for the ...

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1005 防災科研のMPX

 

Evaluating Polarimetric X-Band Radar Rainfall Estimators during HMT

Sergey Y. Matrosov

Journal of Atmospheric and Oceanic Technology

Volume 27, Issue 1 (January 2010) pp. 122-134

Abstract

Different relations between rainfall rate R and polarimetric X-band radar measurables were evaluated using the radar, disdrometer, and rain gauge measurements conducted during the 4-month-long field experiment. The specific differential phase ...

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1003

 

Comparison of Rain Gauge Measurements in the Mid-Atlantic Region

Ali Tokay, Paul G. Bashor, Victoria L. McDowell

Journal of Hydrometeorology

Volume 11, Issue 2 (April 2010) pp. 553-565

doi: 10.1175/2009JHM1137.1

Abstract

A comparative study of daily and monthly rainfall between research and operational gauges was conducted at the mid-Atlantic region. Fifty research tipping-bucket gauges were deployed to 20 sites where each site had dual or triple gauges. The ...

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1010

 

Polarimetric Radar Observations of Convection in Northwestern Mexico during the North American Monsoon Experiment

Timothy J. Lang, Steven A. Rutledge, Robert Cifelli

Journal of Hydrometeorology

Volume 11, Issue 6 (December 2010) pp. 1345-1357

doi: 10.1175/2010JHM1247.1

Abstract

The spatial and temporal variability of convection during the North American Monsoon Experiment (NAME) was examined via analysis of three-dimensional polarimetric radar data. Terrain bands were defined as the Gulf of California (over water) and ...

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1010

 

Effects of Charge Distribution in Thunderstorm on Lightning Propagation Paths in Darwin, Australia

Manabu Akita, Satoru Yoshida, Yoshitaka Nakamura, Takeshi Morimoto, Tomoo Ushio, Zen Kawasaki, Daohong Wang

Journal of the Atmospheric Sciences

Volume 0, Issue 0 ( ) pp.

Abstract

The charge distributions in a thundercloud play an important role in the initiation and propagation of lightning discharges. In order to further understand the effects of charge distributions on lightning discharge, we conducted a VHF lightning ...

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雲の中での電荷分布は発雷の初期化・伝播に重要な働きをしている。

電荷分布が発雷に与える影響を理解するため、VHFによる発雷計を06-07年のモンスーンに実施した。

【帯電したあられの振る舞いが雷の発生に重要。】4/11’11

 

 

The Helsinki Testbed: A Mesoscale Measurement, Research, and Service Platform

Jarkko T. Koskinen, Jani Poutiainen, David M. Schultz, Sylvain Joffre, Jarmo Koistinen, Elena Saltikoff, Erik Gregow, Heikki Turtiainen, Walter F. Dabberdt, Juhani Damski, Noora Eresmaa, Sabine Göke, Otto Hyvärinen, Leena Järvi, Ari Karppinen, Janne Kotro, Timo Kuitunen, Jaakko Kukkonen, Markku Kulmala, Dmitri Moisseev, Pertti Nurmi, Heikki Pohjola, Pirkko Pylkkö,Timo Vesala, Yrjö Viisanen

Bulletin of the American Meteorological Society

Volume 0, Issue 0 ( ) pp.

doi: 10.1175/2010BAMS2878.1

Abstract

CAPSULE: A mesoscale observation network in the Helsinki area—funded and maintained by both public and private sources—demonstrates its value to researchers, forecasters, and the public.

The Finnish Meteorological Institute and Vaisala have ...

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ヘルシンキの観測フィールドの紹介。レーダは4機あり、そのうち、2機は偏波機能を持つ。観測は現業レベル、半現業も含まれる。4/12’11

 

A New Dual-Polarization Radar Rainfall Algorithm: Application in Colorado Precipitation Events

R. CIFELLI, V. CHANDRASEKAR, S. LIM, P. C. KENNEDY, Y. WANG, S. A. RUTLEDGE

Journal of Atmospheric and Oceanic Technology

Volume 0, Issue 0 ( ) pp.

Abstract

The efficacy of dual polarization radar for quantitative precipitation estimation (QPE) has been demonstrated in a number of previous studies. Specifically, rainfall retrievals using combinations of reflectivity (Zh), differential reflectivity (Z...

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412’11

偏波を活用すると、定量観測精度が向上する。偏波を活用すると、粒径分布や粒子判別が可能となる。

Zh、ZDR,Kpdの精度を比較した。

偏波情報を活用した粒子判別(HID)法のアルゴリズムを開発した。雨、混合、氷の判別の目安ができる。

コロラド州立大学のSバンドをもちいている。

* 研究の背景:何がわかっていて、何がわからないのか−偏波による雨量推定精度の向上
* 研究の目的:それがわかると何になる?−雨量推定のアルゴリズムを改良できる
* 研究手段:目的を達成するために何をどうやるの?−R(Zh), R(ZDR), R(Kdp)を地上雨量と比較する。??

4/13’11

 

CPOL Radar-Derived Drop Size Distribution Statistics of Stratiform and Convective Rain for Two Regimes in Darwin, Australia

M. Thurai, V. N. Bringi, P. T. May

Journal of Atmospheric and Oceanic Technology

Volume 27, Issue 5 (May 2010) pp. 932-942

doi: 10.1175/2010JTECHA1349.1

Abstract

This note builds on prior technique development related to the classification of rain types utilizing C-band polarimetric (CPOL) radar measurements. While the prior work was preliminary and limited in scope, the authors elaborate here on the ...

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