scholarly journals ANALISIS KEMUNCULAN AWAN HUJAN BERDASARKAN JENISNYA UNTUK MENDUKUNG KEGIATAN MODIFIKASI CUACA

2015 ◽  
Vol 16 (2) ◽  
pp. 83 ◽  
Author(s):  
Findy Renggono
Keyword(s):  
National Laboratory ◽  
New Method ◽  
Cloud Seeding ◽  
Weather Modification ◽  
Convective Clouds ◽  
The North ◽  
Seeding Material ◽  
Precipitating Clouds ◽  
Seeding Agent ◽  
Rain Cloud

Untuk memenuhi kebutuhan cadangan air di tiga danau yang ada di DAS Larona, telah beberapa kali dilakukan penyemaian awan dengan menggunakan Teknologi Hujan Buatan. Teknologi yang selama ini dilakukan adalah penyemaian awan dari udara dengan menggunakan pesawat terbang sebagai sarana penghantar bahan semainya. Namun akhir-akhir ini di Balai Teknologi Modifikasi Cuaca, BPPT telah mulai dikembangkan teknologi penyemaian awan dari darat yang menggunakan menara. Penempatan menara ini perlu mempertimbangkan unsur meteorologi agar bahan semai secara efektif dapat masuk ke dalam awan yang potensial menghasilkan hujan. Dari data satelit dan penakar hujan didapatkan gambaran secara umum sebaran awan hujan. Dengan melakukan analisis reflektifitas radar diperoleh sebaran awan hujan berdasarkan jenis awan hujannya. Dengan metoda ini diketahui bahwa awan-awan hujan yang muncul di Matano, Timampu dan Tokalimbo kebanyakan awan hujan jenis shallow convective. Awan hujan shallow convective dan convective pada bulan Januari-Maret lebih banyak tumbuh di bagian Utara dan Timur DAS. Di bagian tengah DAS, kemunculan awan hujan lebih sedikit.Kata Kunci: radar, awan hujan, sorowako, modifikasi cuacaCloud seeding project has been carried out in Larona watershed to enhanced the rainfall in this area. Until now the cloud seeding technology has been done by delivering the seeding material directly to the cloud by aircraft. But recently, the National Laboratory of Weather Modification Technology of Indonesia is developing a new method of ground based seeding by building some towers for delivering the seeding agent to the cloud. Location of the tower should consider elements of Meteorology in order for the seeding materials can effectively enter into cloud which potentially produce rain. By doing an analysis of the radar reflectivity obtained the distribution of clouds based on the type of precipitation cloud. With this method it is known that rain clouds that appeared in Matano, Timampu and Tokalimbo are mostly shallow convective clouds. In January-March, shallow convective clouds and convective grew more in the North and East of the Larona watershed. In the central part of the watershed, there is less precipitating clouds appear.Keywords: radar, rain cloud, sorowako, weather modification

A Critical Assessment of Hygroscopic Seeding of Convective Clouds for Rainfall Enhancement

2003 ◽  
Vol 84 (9) ◽  
pp. 1219-1230 ◽  
Author(s):  
Bernard A. Silverman
Keyword(s):  
Scientific Evidence ◽  
Critical Examination ◽  
Policy Statement ◽  
Proof Of Concept ◽  
Randomized Experiments ◽  
Cloud Seeding ◽  
Weather Modification ◽  
Convective Clouds ◽  
Physical Evidence ◽  
Hygroscopic Particles

During the past decade, statistically positive results have been reported for four major, randomized hygroscopic seeding experiments, each in a different part of the world. Experiments on cold convective clouds using hygroscopic flares were carried out in South Africa and Mexico. Experiments on warm convective clouds using hygroscopic particles were carried out in Thailand and India. The scientific evidence for enhancing rainfall from convective clouds by hygroscopic seeding from these four randomized experiments is examined and critically assessed. The assessment uses, as a measure of proof of concept, the criteria for success of any cloud seeding activity that were recommended in the Scientific Background for the 1998 AMS Policy Statement on Planned and Inadvertent Weather Modifications, criteria that required both statistical and physical evidence. Based on a critical examination of the results of these four major, randomized hygroscopic seeding experiments, it has been concluded that they have not yet provided either the statistical or physical evidence required to establish that the effectiveness of hygroscopic seeding of convective clouds to increase precipitation is scientifically proven. The impressive statistical results from these experiments must be viewed with caution because, according to the proof-of-concept criteria, credibility of the results depends on the physical plausibility of the seeding conceptual model that forms the basis for anticipating seeding-induced increases in rainfall. The credibility of the hygroscopic seeding for microphysical effects hypothesis has been seriously undermined because it cannot explain the magnitude and timing of the statistically significant increases in precipitation that were observed. Theories suggesting that the microphysical effects of seeding-enhanced downdraft circulations to produce longer-lived clouds have been advanced; however, in the absence of any supporting physical or model evidence, they must be considered to be in the realm of speculation. These results do not alter this author's basic position; cloud seeding is advocated in situations where it is scientifically and operationally appropriate, and it is strongly recommended that an independent evaluation accompany each research or operational project in order that the science of weather modification benefit from the experience.

A Transformational Approach to Winter Orographic Weather Modification Research: The SNOWIE Project

2019 ◽  
Vol 100 (1) ◽  
pp. 71-92 ◽  
Author(s):  
Sarah A. Tessendorf ◽  
Jeffrey R. French ◽  
Katja Friedrich ◽  
Bart Geerts ◽  
Robert M. Rauber ◽  
...  
Keyword(s):  
Silver Iodide ◽  
Supercooled Liquid ◽  
Cloud Seeding ◽  
Remotely Sensed Data ◽  
Weather Modification ◽  
Before And After ◽  
Orographic Clouds ◽  
Seeding Material ◽  
Airborne Sensors

AbstractThe Seeded and Natural Orographic Wintertime Clouds: The Idaho Experiment (SNOWIE) project aims to study the impacts of cloud seeding on winter orographic clouds. The field campaign took place in Idaho between 7 January and 17 March 2017 and employed a comprehensive suite of instrumentation, including ground-based radars and airborne sensors, to collect in situ and remotely sensed data in and around clouds containing supercooled liquid water before and after seeding with silver iodide aerosol particles. The seeding material was released primarily by an aircraft. It was hypothesized that the dispersal of the seeding material from aircraft would produce zigzag lines of silver iodide as it dispersed downwind. In several cases, unambiguous zigzag lines of reflectivity were detected by radar, and in situ measurements within these lines have been examined to determine the microphysical response of the cloud to seeding. The measurements from SNOWIE aim to address long-standing questions about the efficacy of cloud seeding, starting with documenting the physical chain of events following seeding. The data will also be used to evaluate and improve computer modeling parameterizations, including a new cloud-seeding parameterization designed to further evaluate and quantify the impacts of cloud seeding.

scholarly journals Overview of ground-based generator towers as cloud seeding facilities to optimize water resources in the Larona Basin

2019 ◽  
Vol 276 ◽  
pp. 06025
Author(s):  
Anom Prasetio ◽  
Bambang L. Widjiantoro ◽  
Aulia MT Nasution
Keyword(s):  
Power Plant ◽  
Water Resources ◽  
Power Plants ◽  
Water Volume ◽  
Processing Plant ◽  
Cloud Seeding ◽  
Weather Modification ◽  
Hydropower Plants ◽  
Seeding Material ◽  
Carry Over

The Larona River Basin which cover an area of 2477 km2, including the three cascading lakes: Matano, Mahalona, and Towuti Lakes, is a strategic watershed which acts as the water resource for three hydropower plants that supply 420 Megawatt of electricity to power a nickel processing plant and its supporting facilities and electricity need of the surrounding communities. The maximum and minimum operating levels of Towuti Lake are 319.6 meters (asl) and 317.45 meters (asl) respectively. Total live storage between these two elevations is 1,231,500 m3. Currently, the operation average outflow from Towuti Lake to the power plants is 130.1 m3/second which is resulting in a total annual outflow volume of 4,103,000 m3. By comparing the outflow volume with the live storage volume, it is obvious that present live storage has a limited capability to carry over the capacity from wet to dry years. During a dry year, the outflow drops to 100 m3/second. Thus, the optimization of water resources management in the Larona Basin is important to fulfil the need to produce the energy sources. To deal with the decrease of the Lakes water level, the Weather Modification Technology in the form of cloud seeding is needed to produce rain that will increase the water volume in the Lakes. The dispersion of cloud seeding material into the targeted clouds can be done by surface seeding using the Ground-Based Generator (GBG) which utilize towers to release cloud seeding materials. The tower locations should be in certain altitude or higher locations and amounts in order to operate effectively with optimum results. The water discharges generated from the process is expected in accordance with the planning. The weather modification process is inefficient when the discharge is overflow the spillway channel. Cost incurred is in approximate of US$ $11,133,258.36 if the company is utilizing Diesel Power Plant and Steam Power Plant instead of the weather modification technology.

scholarly journals PEMANFAATAN TEKNOLOGI MODIFIKASI CUACA UNTUK REDISTRIBUSI CURAH HUJAN DALAM RANGKA TANGGAP DARURAT BANJIR DI PROVINSI DKI JAKARTA DAN SEKITARNYA

2013 ◽  
Vol 14 (1) ◽  
pp. 1 ◽  
Author(s):  
Tri Handoko Seto ◽  
Sutrisno Sutrisno ◽  
Sunu Tikno ◽  
F. Heru Widodo
Keyword(s):  
Cloud Physics ◽  
Cloud Seeding ◽  
Solution System ◽  
Cumulus Clouds ◽  
Process Mechanism ◽  
Competition Mechanism ◽  
Convective Clouds ◽  
Seeding Material ◽  
Rainfall Reduction ◽  
Surrounding Areas

Intisari  Pelaksanaan operasi TMC untuk redistribusi curah hujan di Provinsi DKI Jakarta dan sekitarnya dilakukan dengan menggunakan dua metode, yaitu metode mekanisme proses lompatan (jumping process mechanism) dan metode mekanisme persaingan (competition mechanism). Metode mekanisme proses lompatan (jumping process mechanism) dilakukan dengan proses penyemaian awan (cloud seeding) menggunakan bahan semai NaCl yang ditaburkan ke dalam awan menggunakan pesawat terbang. Tujuannya untuk mempercepat proses hujan pada awan-awan Cumulus yang berada di daerah upwind, yang dari radar terpantau bergerak masuk ke arah wilayah Jakarta. Sementara itu, metode mekanisme persaingan (competition mechanism) dilakukan dengan cara membakar bahan semai dalam flare menggunakan wahana penyemaian dari darat (GBG: Ground-Based Generator) yang terpasang di sejumlah lokasi di wilayah Jakarta, mulai dari hulu (daerah Puncak, Bogor) hingga hilir (sekitar Teluk Jakarta). Metode ini bertujuan untuk mengganggu mekanisme fisika awan-awan konvektif yang tumbuh di atas wilayah Jakarta dan berpotensi menjadi hujan. Secara umum, pelaksanaan TMC yang berlangsung selama 33 hari sejak tanggal 26 Januari sampai dengan 27 Februari 2013 berhasil mengurangi intensitas curah hujan dan resiko banjir di wilayah Provinsi DKI Jakarta dan sekitarnya. Selama berlangsungnya pelaksanaan TMC di Provinsi DKI Jakarta, total telah dilakukan 66 sorti penerbangan penyemaian dengan rincian 44 sorti menggunakan pesawat Hercules A-1323 dan 22 sorti menggunakan CASA 212-200 U-616. Total bahan semai NaCl powder yang ditaburkan sebanyak 201,8 ton, sementara dengan GBG telah melakukan pembakaran 486 batang flare di 14 lokasi, dan GBG sistem larutan di 9 lokasi masingmasing selama 158 jam. Berdasarkan data curah hujan historis dari TRMM, curah hujan aktual dari penakar dan TRMM, serta prediksi curah hujan dari GFS diperoleh hasil perhitungan pengurangan curah hujan selama operasional TMC sebesar 20-50%.  Abstract  Implementation of the TMC operations for the redistribution of rainfall in Jakarta and surrounding areas is done using two methods, namely the jumping process mechanism and the competition mechanism. The jumping process mechanism performed by seeding the clouds using NaCl using aircraft. The goal is to accelerate the process of rain on Cumulus clouds in upwind areas, which is observed (using radar) moving in the direction to Jakarta area. Meanwhile, the competition mechanism is done by burning the material seeding in form of flares using Ground-Based Generator installed in several locations in Jakarta, ranging from upstream (Puncak area, Bogor) to downstream (around the Bay of Jakarta). This method aims to disrupt the cloud physics mechanism for the existence of convective clouds that grow in the area of Jakarta and potential rain.In general, the implementation of the TMC which lasts for 33 days from January 26 until February 27, 2013 managed to reduce the intensity of rainfall and the risk of flooding in areas of Jakarta and its surroundings. During the implementation of the TMC in Jakarta, a total of 66 flight sorties have been carried out with 44 sorties using Hercules aircraft A-1323 and 22 sorties using CASA 212-200 U-616. Total seeding material NaCl powder was 201.8 tons, while the Ground-Base Generators have burned 486 flares in 14 locations, and GBG solution system has operated in 9 locations for 158 hours each. Based on historical rainfall data from TRMM, actual rainfall from raingauge and TRMM, and rainfall predictions obtained by the GFS, rainfall reduction during TMC operation was about 20-50%.

scholarly journals A new method for correcting temperature log profiles in low-enthalpy plays

2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Sandra Schumacher ◽  
Inga Moeck
Keyword(s):  
Input Parameter ◽  
New Method ◽  
Geothermal Resources ◽  
The North ◽  
Deep Wells ◽  
Thermal Disturbance ◽  
Drilling Operations ◽  
Crucial Information ◽  
Well Data ◽  
Drilling Time

Abstract Temperature logs recorded shortly after drilling operations can be the only temperature information from deep wells. However, these measurements are still influenced by the thermal disturbance caused by drilling and therefore do not represent true rock temperatures. The magnitude of the thermal disturbance is dependent on many factors such as drilling time, logging procedure or mud temperature. However, often old well reports lack this crucial information so that conventional corrections on temperature logs cannot be performed. This impedes the re-evaluation of well data for new exploration purposes, e.g. for geothermal resources. This study presents a new method to correct log temperatures in low-enthalpy play types which only requires a knowledge of the final depth of the well as an input parameter. The method was developed and verified using existing well data from an intracratonic sedimentary basin, the eastern part of the North German Basin. It can be transferred to other basins with little or no adjustment.

scholarly journals Evaluation of the Wyoming Weather Modification Pilot Project (WWMPP) Using Two Approaches: Traditional Statistics and Ensemble Modeling

2018 ◽  
Vol 57 (11) ◽  
pp. 2639-2660 ◽  
Author(s):  
Roy M. Rasmussen ◽  
Sarah A. Tessendorf ◽  
Lulin Xue ◽  
Courtney Weeks ◽  
Kyoko Ikeda ◽  
...  
Keyword(s):  
Null Hypothesis ◽  
Initial Conditions ◽  
Pilot Project ◽  
Physical Experiment ◽  
Annual Precipitation ◽  
Ensemble Modeling ◽  
Cloud Seeding ◽  
Weather Modification ◽  
Mountain Ranges ◽  
The Impact

AbstractThe Wyoming Weather Modification Pilot Project randomized cloud seeding experiment was a crossover statistical experiment conducted over two mountain ranges in eastern Wyoming and lasted for 6 years (2008–13). The goal of the experiment was to determine if cloud seeding of orographic barriers could increase snowfall and snowpack. The experimental design included triply redundant snow gauges deployed in a target–control configuration, covariate snow gauges to account for precipitation variability, and ground-based seeding with silver iodide (AgI). The outcomes of this experiment are evaluated with the statistical–physical experiment design and with ensemble modeling. The root regression ratio (RRR) applied to 118 experimental units provided insufficient statistical evidence (p value of 0.28) to reject the null hypothesis that there was no effect from ground-based cloud seeding. Ensemble modeling estimates of the impact of ground-based seeding provide an alternate evaluation of the 6-yr experiment. The results of the model ensemble approach with and without seeding estimated a mean enhancement of precipitation of 5%, with an inner-quartile range of 3%–7%. Estimating the impact on annual precipitation over these mountain ranges requires results from another study that indicated that approximately 30% of the annual precipitation results from clouds identified as seedable within the seeding experiment. Thus the seeding impact is on the order of 1.5% of the annual precipitation, compared to 1% for the statistical–physical experiment, which was not sufficient to reject the null hypothesis. These results provide an estimate of the impact of ground-based cloud seeding in the Sierra Madre and Medicine Bow Mountains in Wyoming that accounts for uncertainties in both initial conditions and model physics.

Lightning Frequency and Microphysical Properties of Precipitating Clouds over the Western North Pacific during Winter as Derived from TRMM Multisensor Observations

2007 ◽  
Vol 135 (6) ◽  
pp. 2226-2241 ◽  
Author(s):  
Yasu-Masa Kodama ◽  
Haruna Okabe ◽  
Yukie Tomisaka ◽  
Katsuya Kotono ◽  
Yoshimi Kondo ◽  
...  
Keyword(s):  
North Pacific ◽  
Western North Pacific ◽  
Large Scale ◽  
Tropical Rainfall Measuring Mission ◽  
Radar Reflectivity ◽  
Phase Layer ◽  
Convective Clouds ◽  
Microphysical Properties ◽  
The Tropics ◽  
Precipitating Clouds

Abstract Tropical Rainfall Measuring Mission observations from multiple sensors including precipitation radar, microwave and infrared radiometers, and a lightning sensor were used to describe precipitation, lightning frequency, and microphysical properties of precipitating clouds over the midlatitude ocean. Precipitation over midlatitude oceans was intense during winter and was often accompanied by frequent lightning. Case studies over the western North Pacific from January and February 2000 showed that some lightning occurred in deep precipitating clouds that developed around cyclones and their attendant fronts. Lightning also occurred in convective clouds that developed in regions of large-scale subsidence behind extratropical cyclones where cold polar air masses were strongly heated and moistened from below by the ocean. The relationships between lightning frequency and the minimum polarization corrected temperature (PCT) at 37 and 85 GHz and the profile of the maximum radar reflectivity resembled relationships derived previously for cases in the Tropics. Smaller lapse rates in the maximum radar reflectivity above the melting level indicate vigorous convection that, although shallow and relatively rare, was as strong as convection over tropical oceans. Lightning was most frequent in systems for which the minimum PCT at 37 GHz was less than 260 K. Lightning and PCT at 85 GHz were not as well correlated as lightning and PCT at 37 GHz. Thus, lightning was frequent in convective clouds that contained many large hydrometeors in the mixed-phase layer, because PCT is more sensitive to large hydrometeors at 37 than at 85 GHz. The relationship between lightning occurrence and cloud-top heights derived from infrared observations was not straightforward. Microphysical conditions that support lightning over the midlatitude ocean in winter were similar to conditions in the Tropics and are consistent with Takahashi’s theory of riming electrification.

INVESTIGATION OF RADAR AND ELECTRICAL CHARACTERISTICS OF THUNDERCLOUDS SEEDED WITH A GLACIOGENIC REAGENT IN KARNATAKA, INDIA

2021 ◽  
pp. 112-122
Author(s):  
A.A. SIN'KEVICH ◽  
◽  
B. BOE ◽  
S. PAWAR ◽  
YU. P. MIKHAILOVSKII ◽  
...  
Keyword(s):  
Network Data ◽  
Lightning Flash ◽  
Electrical Characteristics ◽  
North Caucasus ◽  
Flash Rate ◽  
Convective Clouds ◽  
The North ◽  
Lightning Detection ◽  
Karnataka State ◽  
Order Of Magnitude

Characteristics of developing convective clouds (Cu) in Karnataka state (India) during the thunderstorm formation are analyzed using weather radar and lightning detection network data. It is noted that radar characteristics of Cu which produced lightning, exceed those where lightning does not form. The study has shown that the number of negative cloud-to-ground strokes exceeds the number of positive ones by an order of magnitude. The radar characteristics of clouds in India and the North Caucasus are compared. Significant differences in lightning flash rates over the mentioned regions are registered. A low correlation is found between the supercooled volume and the flash rate of negative lightning. The paper also presents the results of studying the dynamic characteristics of four Cu seeded with a glaciogenic reagent. The thunderstorm risk is estimated for the clouds. It is shown that the seeding increases a probability of lightning events.

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