polarimetric　in hydrometeorology

jan 2003- sep 2010

Showing: 1 - 20 of 26

The Utility of X-Band Polarimetric Radar for Quantitative Estimates of Rainfall Parameters

Sergey Y. Matrosov, David E. Kingsmill, Brooks E. Martner, F. Martin Ralph

Journal of Hydrometeorology

Volume 6, Issue 3 (June 2005) pp. 248-262

Abstract

The utility of X-band polarimetric radar for quantitative retrievals of rainfall parameters is analyzed using observations collected along the U.S. west coast near the mouth of the Russian River during the Hydrometeorological Testbed project ...

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X帯レーダの有効性評価。ZDR法。位相のシフトも用いている。減衰補正の効果を検証。D0が0.75mmより大きいときに今回提案する減衰補正が有効。10/6’10

High-Resolution Rainfall Estimation from X-Band Polarimetric Radar Measurements

Emmanouil N. Anagnostou, Marios N. Anagnostou, Witold F. Krajewski, Anton Kruger, Benjamin J. Miriovsky

Journal of Hydrometeorology

Volume 5, Issue 1 (February 2004) pp. 110-128

Abstract

The paper presents a rainfall estimation technique based on algorithms that couple, along a radar ray, profiles of horizontal polarization reflectivity (Z_H), differential reflectivity (Z_DR), and differential propagation phase shift (Φ_DP) from X-...

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Xバンド偏波レーダを精度評価したという話。解析降雨としては、層状の降水から、対流セルの強い雨も含んでいる。ZRとの比較。10/7’10

An Algorithm for Real-Time Rainfall Rate Estimation by Using Polarimetric Radar: RIME

Francesco Silvestro, Nicola Rebora, Luca Ferraris

Journal of Hydrometeorology

Volume 10, Issue 1 (February 2009) pp. 227-240

Abstract

Polarimetric radars provide measurements that describe the shape and dimensions of hydrometeors and are unaffected by calibration, attenuation, and the presence of ice. These measurements can potentially lead to a more detailed description of ...

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イタリアのCバンドで、粒子判別も含めた降水量の定量評価。10/8’10

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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オクラホマのKOUNレーダ。偏波レーダのプロトタイプ。降水量の評価にR(Z)、DSDを地上観測と比較。R(Z)は降雨ごとにバイアスがある。偏波で雨量を求めた場合R(syn)バイアスはほぼ一定。

10/12’10

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 0, Issue 0 ( ) pp.

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 by the Gulf of California (over water), ...

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NAME時期の対流雲の調査。偏波レーダの3次元観測。対流雲の特徴は降水強度ではなく、中央粒径の最小値によって決めることができる。地形によって起きる暖かい雨の過程によって、増雨している。10/15’10

NASA Cold Land Processes Experiment (CLPX 2002/03): Airborne Remote Sensing

Don Cline, Simon Yueh, Bruce Chapman, Boba Stankov, Al Gasiewski, Dallas Masters, Kelly Elder, Richard Kelly, Thomas H. Painter, Steve Miller, Steve Katzberg, Larry Mahrt

Journal of Hydrometeorology

Volume 10, Issue 1 (February 2009) pp. 338-346

Abstract

This paper describes the airborne data collected during the 2002 and 2003 Cold Land Processes Experiment (CLPX). These data include gamma radiation observations, multi- and hyperspectral optical imaging, optical altimetry, and passive and active ...

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NASAの冷たい土地実験の概要。

合成開口レーダと偏波の散乱計を用いて、冬の土地状態（地面の状態）を観測するのが目的。受動型のマイクロ波も用いる。10/21’10

Raindrop Size Distributions and Rain Characteristics in California Coastal Rainfall for Periods with and without a Radar Bright Band

Brooks E. Martner, Sandra E. Yuter, Allen B. White, Sergey Y. Matrosov, David E. Kingsmill, F. Martin Ralph

Journal of Hydrometeorology

Volume 9, Issue 3 (June 2008) pp. 408-425

Abstract

Recent studies using vertically pointing S-band profiling radars showed that coastal winter storms in California and Oregon frequently do not display a melting-layer radar bright band and inferred that these nonbrightband (NBB) periods are ...

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Comparison of Two Raindrop Size Distribution Retrieval Algorithms for X-Band Dual Polarization Observations

Marios N. Anagnostou, Emmanouil N. Anagnostou, Jothiram Vivekanandan, Fred L. Ogden

Journal of Hydrometeorology

Volume 9, Issue 3 (June 2008) pp. 589-600

Abstract

In this study the authors evaluate two algorithms, the so-called beta (β) and constrained methods, proposed for retrieving the governing parameters of the “normalized” gamma drop size distribution (DSD) from dual-polarization radar measurements. ...

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粒径分布を偏波レーダから推定するアルゴリズムとして、β法と抑制法の2通りについて検討した。β法はKdpの誤差に依存し、観測とはあまり一致しない。抑制法がおおむねよい一致を示した。10/25’10

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 0, Issue 0 ( ) pp.

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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オランダ、カバウにおける高密度の気象観測の紹介（関連サイト）。3種のプロファイラ、Xバンドの偏波レーダ、Cの現業レーダ(DeBilt)を含む。観測密度が高いので時間･空間とも数倍のスケールで雨を観測できる。データセットは自由に利用可能。気象･水文学の発展に貢献するだろう。10/26’10

Evaluation of AMSR-E-Derived Soil Moisture Retrievals Using Ground-Based and PSR Airborne Data during SMEX02

M. F. McCabe, H. Gao, E. F. Wood

Journal of Hydrometeorology

Volume 6, Issue 6 (December 2005) pp. 864-877

Abstract

A Land Surface Microwave Emission Model (LSMEM) is used to derive soil moisture estimates over Iowa during the Soil Moisture Experiment 2002 (SMEX02) field campaign, using brightness temperature data from the Advanced Microwave Sounding ...

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地表面の含水量を衛星から評価。地上観測で、偏波放射計(Polarimetric Scanning Radiometer (PSR))を用いている。含水量を推定するモデルはかなり精度が高い×10/26’10

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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偏波レーダの検証用に研究用雨量計と現業の雨量計についてデータ収集したので、日雨量･月雨量で比較した。研究用の雨量計も現業に耐えることがわかった。10/27’10

Characterization of Errors in a Coupled Snow Hydrology–Microwave Emission Model

Konstantinos M. Andreadis, Ding Liang, Leung Tsang, Dennis P. Lettenmaier, Edward G. Josberger

Journal of Hydrometeorology

Volume 9, Issue 1 (February 2008) pp. 149-164

Abstract

Traditional approaches to the direct estimation of snow properties from passive microwave remote sensing have been plagued by limitations such as the tendency of estimates to saturate for moderately deep snowpacks and the effects of mixed land ...

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偏波放射計を用いた積雪把握×10/28’10

Toward a Global Map of Raindrop Size Distributions. Part I: Rain-Type Classification and Its Implications for Validating Global Rainfall Products

Tristan S. L'Ecuyer, Christian Kummerow, Wesley Berg

Journal of Hydrometeorology

Volume 5, Issue 5 (October 2004) pp. 831-849

Abstract

Variability in the global distribution of precipitation is recognized as a key element in assessing the impact of climate change for life on earth. The response of precipitation to climate forcings is, however, poorly understood because of ...

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衛星データと、地上観測(レーダ･ディスドロ)をあわせて全球的なDSDを評価する。10/28’10

Variability of Raindrop Size Distributions in a Squall Line and Implications for Radar Rainfall Estimation

Remko Uijlenhoet, Matthias Steiner, James A. Smith

Journal of Hydrometeorology

Volume 4, Issue 1 (February 2003) pp. 43-61

Abstract

The intrastorm variability of raindrop size distributions as a source of uncertainty in single-parameter and dual-parameter radar rainfall estimates is studied using time series analyses of disdrometer observations. Two rain-rate (R) estimators ...

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北米：スコールラインの通過に伴って、エコーパタン、粒径分布が変化していることを記述。雨量推定に粒径分布を組こむことで、精度向上を確認。Zh法とZDR法の2種の推定法を考察。

降雨のタイプは層状性･対流性・遷移型を考慮。ZDR法は全体としてBβ法よりも精度が高い。層状性ではβ1.4、遷移型では1.5．Bは遷移・対流・層状で200,300、450。1/28’11

NASA Cold Land Processes Experiment (CLPX 2002/03): Local Scale Observation Site

Janet Hardy, Robert Davis, Yeohoon Koh, Don Cline, Kelly Elder, Richard Armstrong, Hans-Peter Marshall, Thomas Painter, Gilles Castres Saint-Martin, Roger DeRoo, Kamal Sarabandi, Tobias Graf, Toshio Koike, Kyle McDonald

Journal of Hydrometeorology

Volume 9, Issue 6 (December 2008) pp. 1434-1442

Abstract

The local scale observation site (LSOS) is the smallest study site (0.8 ha) of the 2002/03 Cold Land Processes Experiment (CLPX) and is located within the Fraser mesocell study area. It was the most intensively measured site of the CLPX, and ...

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地上観測とリモセンの比較。境界層。主に積雪・水文情報。×1/31’11

2/4’11

Evaluation of Incremental Improvements to Quantitative Precipitation Estimates in Complex Terrain

Jonathan J. Gourley, David P. Jorgensen, Sergey Y. Matrosov, Zachary L. Flamig

Journal of Hydrometeorology

Volume 10, Issue 6 (December 2009) pp. 1507-1520

Abstract

Advanced remote sensing and in situ observing systems employed during the Hydrometeorological Testbed experiment on the American River basin near Sacramento, California, provided a unique opportunity to evaluate correction procedures applied to ...

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複雑地形に対するキャリブレーションの手法の開発。現業レーダに応用してうまくいった。

？gap-fillling;段差を埋める方法？

改良点：雪と融解層の高度依存Zに対応するため、距離によってBを変えた。

改良点２：高度が低いレーダが観測する領域を改善した（周囲のデータで埋める）。研究用のレーダを持ちいて埋める。

これらは研究用のレーダでは、地上とレーダのバイアスが最小になるように改善されたが、現業のレーダに用いると、補正がききすぎる。

2/4’11

An Automated Radar Technique for the Identification of Tropical Precipitation

Xiaoyong Xu, Kenneth Howard, Jian Zhang

Journal of Hydrometeorology

Volume 9, Issue 5 (October 2008) pp. 885-902

Abstract

A radar-based automated technique for the identification of tropical precipitation was developed to improve quantitative precipitation estimation during extreme rainfall events. The technique uses vertical profiles of reflectivity to identify the ...

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熱帯性の降雨(暖かい雨)をレーダの鉛直分布から自動判定する。暖かい雨と冷たい雨の線引きをおこなう。アルゴリズムはアメリカの5降雨を元に作成した。暖かい雨と冷たい雨でBβを変更し、観測精度の向上を図った。暖かい雨のBβを用意した。2/16’11

The Soil Moisture–Atmosphere Coupling Experiment (SMACEX): Background, Hydrometeorological Conditions, and Preliminary Findings

William P. Kustas, Jerry L. Hatfield, John H. Prueger

Journal of Hydrometeorology

Volume 6, Issue 6 (December 2005) pp. 791-804

Abstract

The Soil Moisture–Atmosphere Coupling Experiment (SMACEX) was conducted in conjunction with the Soil Moisture Experiment 2002 (SMEX02) during June and July 2002 near Ames, Iowa—a corn and soybean production region. The primary objective of SMEX02 ...

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地上観測と航空機観測から土壌の水分量を測定。2/16’11

A real-time algorithm for the correction of bright band effects in radar-derived QPE

Jian Zhang, Youcun Qi

Journal of Hydrometeorology

Volume 0, Issue 0 (2010 ) pp.

doi: 10.1175/2010JHM1201.1

Abstract

The bright band (BB) is a layer of enhanced reflectivity due to melting of aggregated snow and ice crystals. The locally high reflectivity causes significant overestimation in radar precipitation estimates if appropriate correction is not ...

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融解層の定量評価のために、レーダで観測されたVPRと線形化したVPRモデルを用いて、雨量推定をおこなった。8つの地域･時期の異なる降雨を解析した。2/16’11

A Method for Evaluating the Accuracy of Quantitative Precipitation Estimates from a Hydrologic Modeling Perspective

Jonathan J. Gourley, Baxter E. Vieux

Journal of Hydrometeorology

Volume 6, Issue 2 (April 2005) pp. 115-133

Abstract

A major goal in quantitative precipitation estimation and forecasting is the ability to provide accurate initial conditions for the purposes of hydrologic modeling. The accuracy of a streamflow prediction system is dependent upon how well the ...

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モデルに与えることができるような降水量をレーダから推定する手法について述べる。対象は、実況の観測値と予報値の両方である【水文モデル⇒流出モデル？に与えるようにする】。2/16’11

Coastal Orographic Rainfall Processes Observed by Radar during the California Land-Falling Jets Experiment

Allen B. White, Paul J. Neiman, F. Martin Ralph, David E. Kingsmill, P. Ola G. Persson

Journal of Hydrometeorology

Volume 4, Issue 2 (April 2003) pp. 264-282

Abstract

Radar and rain gauge observations collected in coastal mountains during the California Land-Falling Jets Experiment (CALJET) are used to diagnose the bulk physical properties of rainfall during a wet winter season (January–March 1998). Three ...

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0810にあり。2/17

Evaluation of PERSIANN-CCS Rainfall Measurement Using the NAME Event Rain Gauge Network

Yang Hong, David Gochis, Jiang-tao Cheng, Kuo-lin Hsu, Soroosh Sorooshian

Journal of Hydrometeorology

Volume 8, Issue 3 (June 2007) pp. 469-482

Abstract

Robust validation of the space–time structure of remotely sensed precipitation estimates is critical to improving their quality and confident application in water cycle–related research. In this work, the performance of the Precipitation ...

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PERSIANN-CCSリモートセンシングと人工知能を組み合わせた雲の分類システム

NAME（北米季節風実験）期間中の降水を取り上げ複雑地形下で、季節風期の雲タイプの分類システムの検証をおこなった。積雲系の空間分布、日変動はおおむね捉えられている。高標高部で弱い降水の発生を過小評価する、低地での薄いの発生を過大評価するという傾向があった。高度によって日周期を持つ降水のバイアスが存在した。このシステムは水文モデルに有効である。2/17’11

Evaluation of RadVil, a Radar-Based Very Short-Term Rainfall Forecasting Model

Brice Boudevillain, Hervé Andrieu, Nadine Chaumerliac

Journal of Hydrometeorology

Volume 7, Issue 1 (February 2006) pp. 178-189

Abstract

A very short-term rainfall forecast model is tested on actual radar data. This model, called RadVil, takes advantages of voluminal radar data through vertically integrated liquid (VIL) water content measurements. The model is tested on a dataset ...

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0410に同じ著者の論文あり。

鉛直積算降水量を使った短時間降雨予測の精度を求めた。予測の時間は10分から90分まで。対象領域は4km2から169km2(13×13km？)とした。モデルの名前はRadVilで水文モデルの要求に合うようにした。予測の精度は気象場によっている。VILの時間・空間変化とモデルの精度を組合せ、Vilの時間構造と予測精度の関係を作った。2/18’11

Using a Microwave Emission Model to Estimate Soil Moisture from ESTAR Observations during SGP99

Huilin Gao, Eric F. Wood, Matthias Drusch, Wade Crow, Thomas J. Jackson

Journal of Hydrometeorology

Volume 5, Issue 1 (February 2004) pp. 49-63

Abstract

The 1999 Southern Great Plains Hydrology Experiment (SGP99) provides comprehensive datasets for evaluating microwave remote sensing of soil moisture algorithms that involve complex physical properties of soils and vegetation. The Land Surface ...

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南大平原水文実験で地表面の水分量マップを航空機搭載のLバンド放射計から作成。土壌水分量はRMSで1.8から2.8%で推定できた。2/19’11

The Hydrometeorology of a Deforested Region of the Amazon Basin

Renato Ramos da Silva, Roni Avissar

Journal of Hydrometeorology

Volume 7, Issue 5 (October 2006) pp. 1028-1042

Abstract

A series of numerical simulations were performed to evaluate the capability of the Regional Atmospheric Modeling System (RAMS) to simulate the evolution of convection in a partly deforested region of the Amazon basin during the rainy season, and ...

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アマゾン川流域で森林伐採により、積雲系の降水がどのように変化するかを、領域大気モデルで調べた。積雲系の雲は、日射をさえぎるのは一部なので、不安定を形成する。

土壌水分が多いと形成される降水量が多い。対流雲のフィードバック機構が、モデルで評価可能であった。2/23’11

A Microwave Satellite Observational Operator for Variational Data Assimilation of Soil Moisture

Andrew S. Jones, Tomislava Vukićević, Thomas H. Vonder Haar

Journal of Hydrometeorology

Volume 5, Issue 1 (February 2004) pp. 213-229

Abstract

An observational operator and its adjoint have been created that are suitable for use within variational data assimilation using polarized 6- and 10-GHz passive microwave satellite observations. When used within a variational data assimilation ...

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受動型のマイクロ波センサーを用いて土壌水分量を推定するのに適した、演算子と追随行列を整理した。2/28’11