RESUMO
Measurements and model calculations have been performed to study the effect of high surface albedo on erythemally effective UV irradiance. A central part of the investigation has been a one week measurement campaign at Salar de Uyuni in the Southern part of the Bolivian Altiplano. The Salar de Uyuni, the largest salt lake of the world, is characterized by largely homogeneous surface conditions during most of the year. Albedo measurements performed by an UV radiometer result in a reflectivity for erythemally effective radiation of 0.69+/-0.02. The measurements show hardly any dependency on solar elevation, indicating the homogeneity of the surface and nearly isotropic reflection properties of the Salar. The effects of the high albedo surface on the erythemally effective irradiance, i.e. the UV index (UVI), has been experimentally determined by simultaneous measurements of several UV radiometers located at different sites around and on the Salar. In this context a method for the minimization of systematic deviations between the individual detectors used for the investigation is presented. It ensures the intercomparability of the performed UV measurements within +/-2% which is a distinct improvement compared to the typical absolute accuracy of UV irradiance measurements in the order of +/-5%. For solar elevations around 50 degrees the UVI measured close to the center of the Salar is typically enhanced by 20% compared to the values determined outside. Towards lower solar elevations this increase becomes slightly weaker. The measurements agree well with both, own corresponding 1D and previously published 3D radiative transfer calculations from literature.
Assuntos
Eritema/diagnóstico por imagem , Fótons , Proteção Radiológica , Raios Ultravioleta , Bolívia , Humanos , Cintilografia , Energia SolarRESUMO
El objetivo del presente informe ha sido que la población tome conciencia de los peligros para la salud que conlleva una prolongada exposición a la radiación y que, consecuentemente, adopte medidas preventivas y protectoras en el ámbito de la realidad social y económica del país. Al mismo tiempo la población este informada sobre niveles de radiación que se reciben en diferentes épocas del año
Assuntos
Cooperação Técnica , Radiação , Radiação Solar , Raios Ultravioleta , BolíviaRESUMO
La creciente demanda de materiales mas asequibles y fáciles de producir,ha logrado el desarrollo de un sin número de nuevos materiales de uso tecnológico.Muchos de ellos como los denominados plásticos comunes,estan ampliamente difundidos en le planeta,no solo como elementos de uso cotidiano,sino tambien por la facilidad de implementar plantas industriales.(au)
