人工降雨のための参考文献

4/20’11

衛星から調べた雲の特徴

里村先生　GPS

静岡大学紀要 2004タイ=アジアモンスーン域における可降水量precipitable water vapor (PWV)の変化。「モンスーンブレイク」。NCEP/NCARとの月降水量との比較。

静岡大学紀要　2010　GAME-Tの結果。2001年8月-2006年12月のGPSから求めた水蒸気量。タイの5地点。TMD(タイ気象局)。6年の変化を見た。可降水量の増大と降水量が多い時期は一致している。

蚊降水量と気圧には、乾季の初期には負の相関（気圧が上がると乾く）、プレモンスーン期には正の相関（気圧が上がると湿る）。モンスーンのオンセットとオフセットを可降水量から決める。5/6’11

気象調節協会の論文

＃３５　2002年の業務報告など　4/21’11

＃４１　

An Independent Statistical Evaluation of the Vail Operational Cloud Seeding Program　Silverman

Vail【地名？】におけるシーディングの評価。1997-2005年の長期。Vail川の流域で、種まき効果の評価を行ったところ8ケースのうち5ケースが有効で、6.3%から28.8%の範囲で効果が示された【増雨量ではない？】。もっとも効果が大きかったのはBighorn谷でその北西・南東で効果が小さくなった。種まき効果の時間変化を調べると、対象流域における気流の変化は、多雨年でほぼ同じであった。6/28’11

経済効率の高い種まきをもたらす

Bernard A. Silverman, PhD

Centennial, CO, USA

Abstract: An independent target-control statistical evaluation of the Southern California Edison (SCE) Upper San Joaquin River Basin Weather Modification Program, also known as the Big Creek Cloud Seeding Project, was conducted using Monte Carlo permutation statistics. The cumulative effect of seeding over the entire history of the project through water year 2006 was calculated in terms of confidence intervals because they provide information on the strength of the seeding effect and, thereby, allows informed judgments to be made about its cost-effectiveness and societal value. The effect of seeding on several targets in the Upper San Joaquin River Basin was evaluated using the control(s) that gives the most precise evaluation results possible with the available data. Evidence for positive, statistically significant and cost-effective increases in stream flow after 56 years of seeding was found for Mono Creek and Pitman Creek, but the results for Bear Creek were not statistically significant. Physical studies that help explain the statistical results and that cloud lead to more cost-effective seeding operations are suggested.

南カリフォルニアのサン・ジョークイン川流域のおける人工降雨の評価。多雨年であった2006年の種まきを通じて、種まきの効率を議論する。56年の種まきの記録からモノ谷、ピットマン谷では効率の良い気流が見つかったがベアー谷では有意な結果が得られなかった。統計的結果を説明するために役に立ち、経済効率の高い種まきをもたらす物理的な研究を提案する【cloud→could？】

30+ Winter Seasons of Operational Cloud Seeding in Utah

Don A. Griffith, Mark E. Solak, and David P. Yorty

North American Weather Consultants, Inc.

Sandy, Utah

Abstract: North American Weather Consultants (NAWC) has conducted operational winter cloud seeding programs in many of the mountainous areas of Utah since 1974. The goal of these programs has been to enhance winter snowpack accumulation in several mountainous target areas throughout the State. Studies have demonstrated that a large majority of the annual runoff in Utah streams and rivers is derived from melting snowpack, which explains the focus on wintertime seeding. Augmented water supplies are typically used for irrigated agriculture or municipal water supplies. Programs and typically funded at the county level with cost-sharing grants from the Utah Division of Water Resources.

NAWC(北アメリカ気象コンサルタント、企業名)は1974年以来、ユタ州の人工降雪事業にかかわっていた。30年の効果をまとめた。

Cloud seeding accomplished using networks of ground-based, manually operated silver iodide generators located in valley or foothill locations upwind of the intended target mountain barriers. As such, these programs are classified as orographic winter cloud seeding programs. Orographic winter cloud seeding programs are typically categorized as those with the highest level of scientific support based upon capability statements of such organizations as the American Meteorological Society, the World Meteorological Organization, and the Weather Modification Association.

種まきの対象は冬季の地形性の降雪を対象としている。

NAWC historical target/control evaluations of these Utah programs based upon high elevation precipitation and snow water content observations indicated a range of apparent increases in target area average precipitation or April 1st snow water content of 3-21%.

人工降雪の効果は3から21%である。

The Utah Division of Water Resources conducted an independent assessment of the seeding programs in 2000. That assessment confirmed that NAWC indicated increases in snow water content, and then took the additional step of estimating the increases in annual streamflow resulting from the estimated increases in snow water content. Average annual increases from four seeded areas were estimated to total 249,000 acre-feet. Factoring in the cost of conducting these programs resulted in an estimate of the average cost of the augmented runoff to be $1.02 per acre-foot.

コストは1エーカー・フィート【約1,200t】当たり1.02ドルであった。6/30’11

Six Hourly Analyses of the Bridger Range Randomized Winter Orographic Cloud Seeding Experiment

Arlin B, Super, Saint Cloud, Minnesota and James A. Heimbach, Jr., Sprinvale, Maine

・ブリジャーレンジ山（モンタナ州）における無作為種まき実験の6時間解析

ブリジャーレンジ山で、1970年代に山岳性降雨に対して種まき実験が行われていた。24時間解析の結果はすでに報告しているので、今回は6時間解析の結果を示す。結果は、気象状況が山岳性の形成に助けとなるようなときに、種まきが有効であった。雲頂と雲厚で雲を分けることが有効である。

前回の報告が最終でないので、さらなる無作為実験が望まれる.6/30’11

Evaluation Plan for a Snow Enhancement Experiment in Australia

Michael J. Manton1, Jingru Dai1, and Loredana Warren2

オーストラリアにおける包括的な冬季降雪雲に対する人工降雨の効果を評価した。

5か年の実験で100を超える5時間実験で80%の人工降雨の機会があるだろう【事前評価？】。ブートストラップ法によって、20%の増雨が10%基準で評価された。

An Assessment of the Environmental Toxicity of Silver Iodide【ヨウ化銀】 - With Reference to a Cloud Seeding Trial in the Snowy Mountains of Australia

Bruce D. Williams1 and John A. Denholm2

環境に対するヨウ化銀の毒素の評価。オーストラリア南ウェールズで実施。対象領域は1000�q四方。7/1’11

An 'Aerosol Effect' Detected in Winter Orographic Clouds but an Effect on Precipitation Could Not be Determined

Edward (Ward) Hindman

The City College of New York, New York City

Seeding Optimization for Hail Prevention with Ground Generators

Jean Dessens1, Claude Berthet1, and Luis A. Sanchez2

Abstract: An evaluation method of hail prevention by silver iodide ground seeding generators is developed. The method is based on correlations between the point hailfall intensities measured with hailpads and the silver iodide released prior to the hailfalls in the "feeding areas" where the hail cells developed. The time unit for the correlations is the day, but days can be aggregated together after data normalization. Former evaluations have shown that the number of hailstones larger than 0.7 cm is mainly responsive to the amount of seeding material released in a 13-km radius area centered on the place where the storm was developing 80 min before the hailfall, and that the seeding effect can be detected only for the days with at least 15 hailpads.

In this paper, the method is applied to 24 major hail days with seeding recorded in the past 20 years in a hailed region north of the Pyrenees. For each day, 15 to 42 point hailfalls have been recorded, and they are used to compute the best negative daily correlation between hailfall intensity and seeding amount by moving the feeding area around its first approximate position. With this seeding area optimization, all the daily correlations are negative (more seeding, less hail), but they are weak, with a correlation coefficient reaching about about r=-0.3 in only half of the cases. For the whole hailfall sample (561 hailfalls), the correlation computed with the ideal feeding areas determined as indicated above is r = -0.22, significant at the 0.01 level, subject to the data independency hypothesis. In average, the distance from the middle of the feeding area to the hailfall corresponds to a storm travel time of 66 min, but a numerical simulation of the seeding particle trajectories with the Meso-NH model suggests that the generators must be started at least 45 min before the storm travels above them.

An Atmospheric Thermodynamic Model of The Convective Storm Process Types in Mendoza (Argentinta)

Raúl Pérez, Enzo Barlotta and Laura Ross

Abstract: The DCPIM (Deep Convection Process Identification Model) index uses only surface meteorology data to forecast the convective storm class of Mendoza (Argeninta). The DCPIM model did not guess right the forecast in about five percent of the studies cases. Then in order to improve the forecast model, we are adding vertical atmospheric information at the index calculation using the radiosonde on Santiago (Chile) and El Plumerillo (Mendoza). This index is calculated by correlating four surface variables: pressure Ps (mb), temperature Ts (°C), dewpoint DPs (°C) and ground ultraviolet solar radiation index UV. Furthermore, two additional atmospheric variables at the 500 mb level were considered: temperature T500 in °C, and dew point DP500 in °C at the 500 mb pressure level. The data was taken from radiosonde over Mendoza and Santiago (Chile). We collected 1551 samples, between September 2007 and April 2008. These data were statistically processed, obtaining a multivariate model for each storm convective process class (TPC) in Mendoza. From this correlation, we can observe that the class and severity of the storm convective process do not depend on the dew point at the 500 mb level (DP500), but depend on surface dew point value. This is associated with the fact that the vertical ascendant movement of the circulation air feeds the storm process carrying the water vapor from the ground to upper levels. Moreover, the class and severity of the convective process depends on the vertical temperatures difference between both levels Ts and T500, and is associated with the heat flux transfer by thermal conductivity and natural convection. We conclude from the above result, that for higher values of the temperature difference and surface dew point, a more complex and severe storm convective process in Mendoza is expected. The thermodynamic calculations performed by the multivariate model were consistently compared with GOES satellite image, the C and S band radar, and its TITAN system.

アルゼンチンの話。深い対流の指標となるDCPIMは地上観測のみで計算されるものであるが、上空の情報を加えて精度を上げる。情報として、メンドーサとチリのサンチアゴのゾンデを用いた。

熱力学の結果をGOES,CとSのレーダ、TITANと比較した。7/7’11

４０

A Statistical Evaluation of the Kern River Operational Cloud Seeding Program

Bernard A. Silverman, PhD

Centennial, CO, USA

Abstract: A target-control statistical evaluation of the Kern River Basin operational cloud seeding program was conducted using ratio statistics. The cumulative effect of seeding from water year 1977 through water year 2006 was calculated in terms of confidence intervals because they provide information on the strength of the seeding effect whereas null hypothesis significance tests infer only whether there is any seeding effect at all. The effect of seeding on several targets in the Kern River Basin was evaluated using the controls that give the most precise evaluation results possible with the available data. Evidence for positive, statistically significant and cost effective seeding effects were found at all 3 sites in the Kern River Basin that were evaluated with estimated increases in streamflow due to seeding ranging from +8.4% to +12.2%, depending on the target location. Physical studies that help explain the statistical results and that could lead to more cost-effective seeding operations are indicated.

3流域で、現業に用いられている人工降雨の効果を評価した。90%の角度で増雨が認められた。7/8’11

Pooling of the estimates of the seeding effects for the Kern River, Kings River, and San Joaquin River Basin operational cloud seeding programs indicated that the common effect of seeding on the three River Basins is +6.4% with 90% confidence that the true effect of seeding is somewhere between +3.9% and +9.0%. The probability that the seeding effect is greater than 0% and 1% (threshold of cost-effectiveness) are both 100%. Thus, there is a strong statistical evidence in support of the hypothesis that cloud seeding in the watersheds of the Southern Sierra Nevada Mountains is a cost-effective technology for increasing streamflow by significant and societal important quantities

南ア