Perceived change in risk of natural disasters caused by global warming

Natural hazards causing disasters that lead to human suffering are as much a product of the social, political and economic environment as they are of the natural environment. It follows, therefore, that the risk associated with natural hazards is in part a social construct that, as Young (1998) has pointed out, is perceived differently by all of us and must be defined with this mind. For example, risk is defined by Emergency Management Australia (1995) as the perceived likelihood of given levels of harm (AU)

El niño - oscilación del sur y algunas series de temperatura máxima y brillo solar en Costa Rica

Se analizan algunas de las características de "El niño-oscilación sel Sur (ENOS) y su posible relación con la distribución espacial y temporal de las anomalías de valores meensuales de temperatura máxima y brillo solar, para algunas regiones seleccionadas en Costa Rica. Las series son primero desestacionalizadas en Costa Rica. Las series son primero desestacionalizadas y luego suavizadas para disminuir la contribuci:n de componentes de período menor que un año aproximadamente. En este priocedimiento se usan las técnicas de promedios móviles y el análisis de Fourier. En especial, las series de temperatura muestran fluctuaciones del orden de 0.5o a 10C que podrían estar asociados al fenómeno ENOS. El brillo solar muestra alguna consistencia con los resultados de la temperatura máxima, sin embargo su comportamiento es más dificil de ser interpretado. En casi todas las estaciones analizadas, la temperatura muestra una tendencia positiva del orden de 0.5oC en las últimas dos décadas, consistente con la idea de un calentamiento regional (AU)

Atlas of the tropical Pacific ocean annual cycle

Data for this Tropical Pacific Ocean Atlas comes from monthly gridded analyses of temperature and current data over a ten year (1983-1992)period generated by an ocean-data assimilation system at the National Meteorological Center, Washington D.C. This atlas showsmaps of the long-term mean, monthly standar deviation, mean anual cycle for suface and subsurface quanties of the tropical Pacific Ocean. The main focus of this atlas is subsurface variations, but the surface wind-stress curl and sea-surface temperature are also included for completeness. The main variables considered here are subsurface temperature, currents, and the depth of the 20ºC isotherm during the course of the annual cycle are also shown. Data are shown on level surfaces at selected depths, depth integrated, and on meridional and zonal cross sections (AU)

Variaciones de la temperatura superficial del mar en Puerto Chicama y del índice de oscilación del sur : 1925 - 1992

El propósito del presente trabajo es presentar una descripción de las principales variaciones de la temperatura Superficial del Mar (TSM) en el Puerto de Chicana (07o42'S-79o27'W) y del índice de oscilación del Sur durante el periodo de 1925 a 1992. Este trabajo empieza precisando, que los datos de TSM de Chicama, (actualmente renominado Puerto Malabrigo) constituyen la seri más larga y confiable del país, se inicio en diciembre de 1924 con dos mediciones diarias hasta 1969 y a partir de esta fecha se realizan tres mediciones diarias. Luego se describe en la escala de tiempo, la presencia de anomalías de temperatura en grupos de años y escasas veces en un solo añ y se define el inicio y duración del evento en fucnión de las desviaciones estandart mensuales y anuales, para despues caracterizar eventos cálidos o fríos y compararlos con los IOS (AU)

Global warming and geographic information : An assessment

This paper is the third of a trilogy on environment issue problem-solving and the use of geographic information. The two predecessor papers (1989 and 1990 Proceedings) dealt with local air quality issues and air pollution (1989) and the Clean Air Act of 1990 and its regional/national geographic consequences (1990). This paper deals with the study, using geographic information systems, of local and regional consequences of global environmental issues, e.g., stratospheric ozone depletion and possible climate change (e.g., sea level rise). The current status of and uncertainties over the adequacy of scientific evidence will be evaluated for their public policy consequences. Ways to estimate the positive and negative effects of climate change at the local, regional and national level -- public health, income change, economic development, trade, food supply, and others -- will be discussed and assessed. Proposals for improved geographic information will be set for forth (AU)

Variability of the earth's climate

climate of our planet has remained within a range compatible with life since several billion year. Theories of star evolution suggest that the amount of heat emitted be the sun increased be about 10

since 4 10º years, so that several factors or the climatic system, such as the chemical composition of the atmosphere, must have changed in orderto maintain the air temperature within a range permitting the occurrence of abundant liquid water at the earth's surface (AU)

The greenhouse effect

greenhouse effect on the earth is identified by the difference between the effective radiating temperature of the planet and is surface temperature. The difference between the energy emitted by the surface and that emitted upward to space by the upper atmosphere quantified it; it can therefore be defined as the long wave energy trapped in the atmosphere (AU)

The tropospheric cycles of methane and other hydrocarbons

Methane and the numerous nonmenthane hydrocarbons (NMHC) are important participants in the photochemical reaction cycles in the troposphere. methane is with a global a mixing ratio of 1.7 ppm the by far most abundant and also most important hydrocarbon compound in the troposphere. As a result of the long atmospheric residence time of methane, its distribution is relatively uniform and the gradient between the northern and southern hemisphere is only about 0.1 ppm (AU)

The physics and dynamics of the climate system : Simulation of climate

physical basis of numerical modelling of climate is outlined, using atmospheric models as an example. The use and verification of climate models is described, illustrated with data from simulations made with meteorological office models (AU)

Bioclimatic belts of west Europe : Relations between bioclimate and plant ecosystems

Bioclimatology is an ecological science which seeks to clarify existing relationships between living organisms (Biology) and limate (Physics). Amound the bioclimatic models and indices which allow demostration of this correlation, the thermicity index [It= (T+m+M)10] and bioclimatic belts are of particular usefulness and predictive value. In our view, the bioclimatic belts are primarily each one one of the thermoclimatic spaces delimited be bioindicators, recognizable in the terrestrial environment in altitudinal or latitudinal zonation. Such thermoclimatic spaces are delimited on determined values of the thermicity index or thermotypes (e.g., thermo-, meso-, supra-, oro-, etc) (AU)

Climatic fluctuation of temperature and air circulation in the Mediterranean

global warming is tested in the mediterranean area during the last 45 year using SST and 1000/500 mb thickness data, in order to avoid urban effects. The area is divided in two parts vis. The west and the east mediterranean. Since wrming is not apparent in the east mediterranean but only during the last year, the time series of surface pressure and relative geostrophic vorticity were examined for possible explanations. It is found that there exists a continuous and considerable increase of the mean vorticity in the extreme east mediterranean, meaning increased frequency and/or strength of N. winds there, causing a delay of the warming. The opposite phenomenon appeared in the extreme West Mediterranean where increased S. winds may contribute to the warming there (AU)

The phenomenon of cyclogenesis over the Aegean Sea

Cycloginesis over the Aegean Sea is considered to be a very rare phenomenon, but highly related to the weather in greece. For this reason, a period of 18 years (1963-1980) of grid data information will be analyzed, in order toidentify the cases of cyclogenesis over the area of interest. This "Climatology" wil result to certain categories, according to their development criteria. The data used for this studyis grid points of geopotentil height and temperature, being recorded at the significant levels for the above mentioned period (AU)

Some aspects about the climate/vegetation relationships in the Iberian Central System

Iberian Central System (Spain-Portugal) has the suitable conditions to make a phytoclimatic study. We have realized as example of these bioclimatic procedures, a study about linear regression of it (thermicity index of Rivas-Martinez) on altitude. The results are given in the present paper (AU)

The last climatic cycle and past ocean changes

During the last 150.000 years, the earth's climate alternated from warm conditions to cold conditions. The peak of the last glaciation occurred about 18.000 years ago and a deglaciation led to the present climatic pattern. In order to reconstruct past climatic and past oceanographic conditions, geologists must define proxy - data, which describe various climatic parameters in the past and dermine the time scaleof the records of these proxy - data. The age of the sediment is determined by absolute dating either by the carbon - 14 method (for the last 40.000 years) or by uranium series disequilibrium (for the last 300.000 years). A good stratigraphy for marine sediments can also be deribed from the oxygen isotope record of planktonic and benthic faraminifera, which partly reflects the variations of the volume of ice stored over the high - latitude continents. (AU)

Basic concepts of climate modelling

climate system consists of the atmosphere, the hydrosphere, the cryosphere, the lithosphere and the biosphere. The difficulty of modelling this system and its variations is related not only to the complexity of each of these physical entities, but also to their interactions. Moreover the large difference between their characteristic time prevents the climate to ever reach an equilibrium. For simulating the climate variations at a specific time scale, the slow parts of that system are thus considered as prescribed boundary conditions to the more "mobile" ones (for example, the dynamics of the ice sheets are not taken into account for the interannual climate variability). (AU)