Estudio prospectivo : Los futuros desastres en México

Trabajo que trata sobre los futuros desastres en México; el trabajo se compone de tres partes, a saber: 1.Breve exposición de las bases teóricas y metodológicas para la construcción de la prospectiva, 2.Visualización de los desastres para el próximo siglo, 3.Diseño de los posibles escenarios de la Protección Civil y su construcción futura. La primera parte esta basada en los planteamientos formulados por el Dr. Tomas Milkos, para desarrollar una prospectiva sobre los desastres y la Protección Civil en México, conforme las siguiente premisas: 1era.Descripción de los futuros, 2da.Visualización del futuro, 3era.diseño del futuro, y 4ta.Construcción del futuro. En donde dichas premisas corresponderán al desarrollo de la segunda y tercera parte de este trabajo, que consiste en visualizar los desastres para diseñar escenarios y obtener algunas líneas o estrategias a adoptar para la construcción de la Protección Civil

Severe local storms

Severe weather associated with thunderstorms (tornadoes, hail, high winds, and flash floods) is reviewed with emphasis on the processes that are responsible. The basis for forecasting severe thunderstorms in reviewed. The parts of the world that are most vulnerable to various kinds of severe weather and the nature of the threats are described. The current state of the climatology of severe thunderstorms and problems and importance of improving climatological information are described. The lack of high-quality climatological information makes it very difficult to determine differences in event occurrence during different periods of the El Niño-Southern Oscillation (ENSO) in most of the world and almost impossible to detect changes associated with global climate change. It is argued, however, that the threats from severe thunderstorms are generally underestimated in many parts of the world. In genera, the effects of severe local storms are concentrated in a small number of events. Death tolls and damage in "average "years are typically smaller than the totals from individual events in other years. As a result, maintaining public awareness and preparedness activities is difficult since the threat of rare, extremely damaging events, is small at any individual location and time. (AU)

Snow avalanches

For alpine countries, avalanches represent one of the major hazards, threatening people on villages as well as on highways and railways. Measures have to be taken to reduce the avalanche risk. Avalanche hazard mapping, as a basis for land use planning, and avalanche warning are the most cost - effective measures to reduce or even avoid avalanche exposure. Long - term technical measures, such as supporting structures, deflecting dams and afforestations, or short - term measures, such as avalanche forecasting, artificial avalanche release of evacuation, might be chosen to reduce the avalanche risk to an acceptable level. It is important to evaluate the different measures within the framework of an overall risk management procedure. (AU)

El Niño Update

Intense warming of the ocean waters across the Eastern and Central Tropical Pacific Ocean, due to the phenomenon known as the El Niño/Southern Oscillation (ENSO), has developed since March 1997. The El Niño developed very rapidly during April-May, and reached high intensity by June. This event is comparable in magnitude and extent to the 1982/83 episode, which was one of the strongest El Niño of the century. Prediction products from several prediction centres around the world indicate these conditions will probably persist during the northern hemispheric spring season of 1998. Based on past warm episodes and on current long-range forecasts, the El Niño is expected to weaken during the late spring and early summer of 1998. Features accompanying the current El Niño include: abnormal patterns of rainfall and cloudiness over most of the global tropics, a nearly complete shut-down of the normal easterly winds across the entire tropical Pacific and abnormal air pressure patterns throughout the global tropics. Thus far, the primary El Niño impacts have been in the tropics and subtropics, and across the eastern South Pacific and Central South America. These has also been a dramatic decrease in tropical storm and hurricane activity across the subtropical North Atlantic and an expanded area of favorable conditions for tropical cyclone activity over the eastern North Pacific. It is summary of: (i) our knowledge of the El Niño phenomenon, (ii) its associated impacts on a global scale, and (iii) forecast information for the coming months. This Update is compiled from a variety of scientific sources including several major global climate prediction centres, and is intended to address the questions and concerns of an audience that ranges from the general public to the policy maker. The background information (part 1 of the Update) is covered in somewhat greater detail in this issue. Future updated will focus primarily on climate monitoring and forecast information (part 2 of this Update) which will be updated each month

Un método gráfico para el pronóstico de oleaje durante huracanes en el Caribe adyacente a Costa Rica

A simple graphic method for wave forecasting during the occurreence of hurricanes in the Caribbean adyacent to Costa Rica is presented. This method utilizes the basic parameters which are reported by the services of meteorological information. Based on the study of parameters which characterize a hurricane: central pressure, speed and direction of movement, and radius of maximum winds, carried aut by Lizano and Fernández (1996), combinations covering all types of hurricanes which may generated in the region were made. Utilizing a numerical wave generation model, the wind and wave hurricane conditions asociated with the different combinations of those parameters were simulated. An example (Hurricane Joan in 1988) is provides, in order to carry out a wave forecast with the typical hurricane parameters (AU)