Randomized convective cloud seeding experiment in extended areas in Cuba (EXPAREX)

Abstract

The Randomized Convective Cloud Seeding Experiment in Extended Areas (EXPerimento aleatorizado de siembra de nubes en AReas EXtensas, EXPAREX) is being implemented in Camagüey, Cuba and adjacent regions from August 2005 as the continuation of a previous successful experiment (PCMAT), held in the period [1982][1983][1984][1985][1986][1987][1988][1989][1990]. The first season of the experiment was exploratory and was focused on upgrading facilities, equipment and software, including an An-26 instrumented aircraft and the 10-cm MRL-5 weather radar. It was aimed at implementing methodologies and testing the application of the experimental design, excluding the randomization scheme, which was scheduled to be started in the second experimental year, in the rainy season of 2006. The field operations of the confirmatory phase started only in October, 2006, when seven experimental units, treated under a randomized scheme, were qualified. In the 2007 experiment, 13 more experimental units were processed. The general description, experimental design, procedures and characterization of the first two experimental seasons of the confirmatory phase of EXPAREX are presented in this work. Is it shown that the experimental clouds processed in the first two seasons of the experiment have similar characteristics to the PCMAT clouds, so that the conclusions of previous physical research are applicable. Key words: cloud seeding, precipitation enhancement, cloud physics, convective clouds RESUMO: EXPERIMENTO ALEATÓRIO DE SEMEADURA DE NUVENS CONVECTIVAS EM ÁREAS EXTENSAS EM CUBA (EXPAREX). O Experimento Aleatório de Semeadura de Nuvens Convectivas em áreas extensas (EXPAREX) vemsendo realizado em Camagüey, Cuba e em regiões adjacentes, desde agosto de 2005, como continuação de experiência anterior bem sucedida (PCMAT) realizada entre 1982 e 1990. A primeira temporada do experimento foi exploratória e concentrou-se na modernização das instalações, equipamentos e software, incluindo um avião An-26 instrumentado e um radar meteorológico MRL-5, de comprimento de onda de 10 centímetros. Nesta fase destinou-se a aplicar e testar metodologias, além de definir o desenho experimental, com exclusão do regime de aleatoriedade, que estava programado para ser iniciado no segundo ano, na estação chuvosa de 2006. As operações de campo da fase de confirmação apenas se iniciaram em outubro de 2006, quando sete unidades experimentais, tratadas sob um regime aleatório, foram qualificadas. No experimento de 2007, mais 13 unidades experimentais foram processadas. A descrição geral, delineamento experimental, procedimentos e caracterização das duas primeiras estações experimentais da fase de confirmação de EXPAREX são apresentados neste trabalho. É mostrado que as nuvens experimentais tratadas têm características semelhantes às nuvens do PCMAT, indicando que as conclusões da investigação física obtidas anteriormente são aplicáveis. Palavras-chave: semeadura de nuvens, aumento da precipitação, física de nuvens, nuvens convectivas. 516Martinez-Castro ...

Study of the dispersion of AGI emitted from ground-based generators using the WRF-Chem model

“…This experiment was carried out in an area of the central-eastern region of Cuba centered in the city of Camagüey, via dynamic seeding with silver iodide pyrotechnics from aircraft (Martínez et al, 2011[a,b]). Simultaneously, in another region near the eastern end of Cuba, the method of dispersing silver iodide aerosol from ground-based acetone ignition generators was tested by the Chilean company Hidromet S.A (Martínez et al, 2011a). The equipment had to be installed on hillsides or mountain tops to ensure that most of the reagent could reach the convective clouds.…”

“…According to the technical characteristics of the pyrotechnic flares PV-26-01 (Martínez et al, 2011a) used in the second program of artificial increase of rain in Cuba in 2005, at -5 º C, 1 g of AgI contributes 10 13 ice nuclei. Hence, for the static seeding to occur about 0.1 ng/m 3 would be necessary to obtain one nucleus per liter.…”

“…This seeding method aims at introducing a large number of ice nuclei from 100 to 1000 nucleus/liter, so that massive glaciation occurs in the seeded area (Woodley et al, 1982). Many studies have shown that the application of the dynamic hypothesis increases the horizontal extension and lifetime of the seeded cloud as well as its accumulated rainfall (Simpson et al, 1967;Woodley et al, 1982;Rosenfeld and Woodley, 1993;Koloskov et al, 1996;Silverman, 2001;Martínez et al, 2011a).…”

Recovery Method for Emergency Situations with Hazardous Substances Emission into the Atmosphere

“…It has been established that well-developed convective clouds with a thickness (thickness) of at least 2.5 km with a temperature at the upper limit of not more than -6℃ are suitable for artificial precipitation [17]. Rainfall begins to fall from the cloud 8-12 min after the introduction of the reagent and, depending on the power and water supply of the cloud, lasts 20-50 min or more.…”