scholarly journals Ultraviolet radiation climatology of the Earth`s surface and lower atmosphere. Final report

1999 ◽  
Author(s):  
S. Madronich ◽  
K. Stamnes
1972 ◽  
Vol 48 ◽  
pp. 231-233
Author(s):  
Chikara Sugawa ◽  
Chuichi Kakuta ◽  
Hideo Matsukura

Solar activity may affect the rotation of the solid Earth by coupling between the lower neutral atmosphere and the solid Earth. It attacks directly the lower atmosphere in the non-axially symmetric mode and may trigger off variation of the amplitude of the annual terms in the polar motion. The indirect effect of solar activity may be associated with some proper oscillation of the atmospheric coupling with the ocean in the axially symmetric mode of the atmospheric motion. The shift of airmass along the rotating axis of the Earth corresponds well with the changes of the Earth's rotational velocity and the Chandler amplitude in the polar motion for long time variation.


Author(s):  
Renata Chadyšienė ◽  
Aloyzas Girgždys

The paper presents the assessment of ultraviolet radiation from technical sources. It has been determined that the intensity of UVA radiation is about 10 times higher than the intensity of radiation of UVB. It has been investigated that the intensity of UV radiation during the welding process nonlinearly depends on the strength of the current, namely, if the strength of the current is reduced by 60%, the intensity of UV radiation is reduced by 20%, it also depends on the distance from the source, namely, if the distance is increased 10 times, the intensity of UV radiation is reduced about 25 times. The dose of UVA and UVB radiation from various resources is calculated. Comparison with the minimum erythema dose is submitted. It has been obtained that when the strength of the current is 315 A, the UV radiation dose exceeds 1 MED, namely, UVA ∼ 3000, UVB ∼300 times. After having carried out the experiment it has been found that the UV radiation emitted from a welder comprises about 80% of UVA, and about 20% of UVB. The results of investigation made in a solarium show that UV radiation from lamps comprises 98% of UVA radiation and 2% – of UVB radiation, while in the Sun rays reaching the Earth UV radiation comprises 96% of UVA and 4% of UVB. Santrauka Darbe radiometriniais metodais nustatyti ir įvertinti dirbtinių šaltinių skleidžiamos ultravioletinės alfa ir beta spinduliuotės (UVA ir UVB) intensyvumo pokyčiai ir apskaičiuota įvairių šaltinių sukuriama UVA ir UVB spinduliuotės dozė. Nustatyta, kad suvirinimo proceso metu skleidžiamos UV spinduliuotės intensyvumas priklauso nuo šaltinio intensyvumo (sumažinus šaltinio intensyvumą apie 60 %, UV spinduliuotės intensyvumas sumažėja apie 20 %) bei nuo atstumo nuo šaltinio (padidinus atstumą 10 kartų UV spinduliuotės intensyvumas sumažėja apie 25 kartus). Įvairių šaltinių sukuriama UVA ir UVB spinduliuotės dozė palyginama su minimalia eritemine doze. Gauta, kad suvirinimo metu, esant 315 A elektros srovės stipriui, UVA spinduliuotės dozė 1 MED viršija apie 3000, UVB ~ 300 kartų. Nustatyta, kad apie 80 % iš suvirinimo aparato skleidžiamos UV spinduliuotės yra UVA, o apie 20 % – UVB. 98 % soliariumo lempų skleidžiamos UV spinduliuotės yra UVA ir 2 % – UVB, gi iš Žemę pasiekiančios Saulės UV spinduliuotės 96 % yra UVA ir 4 % UVB. Резюме Радиометрическими методами определены изменения УФА- и УФБ-излучений некоторых техногенных источников, а также рассчитана доза УФА- и УФБ-излучений этих источников. Установлено, что в среднем интенсивность УФА-излучения в 10 раз сильнее интенсивности УФБ-излучения. Установлено также, что в процессе сварки интенсивность испускаемого УФ-излучения зависит от интенсивности источника: при снижении интенсивности источника на 60% интенсивность УФ-излучения снижается приблизительно на 20%; при увеличении расстояния от места сварки в 10 раз интенсивность УФ-излучения снижается приблизительно в 25 раз. Рассчитана доза УФАи УФБ-излучений, создаваемая различными техногенными источниками. Представлено ее сравнение с минимальной эритемной дозой. Получено, что во время сварки при силе электрического тока 315 А доза УФА-излучения превышает 1 МЭД в 3000 раз, а УФБ-излучения – в 300 раз. Экспериментальными исследованиями получено, что испускаемое при сварке УФ излучение на 80% состоит из УФА-излучения и на 20% – из УФБ-излучения. В соляриуме, где был проведен эксперимент, УФ-излучение ламп состоит на 98% из УФА лучей и на 2% из УФБ лучей. Для сравнения: околоземное УФ-излучение Солнца в Литве состоит в среднем на 96% из УФА лучей и на 4% из УФБ лучей.


Atmosphere ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 324
Author(s):  
Antti Lipponen ◽  
Simone Ceccherini ◽  
Ugo Cortesi ◽  
Marco Gai ◽  
Arno Keppens ◽  
...  

AURORA (Advanced Ultraviolet Radiation and Ozone Retrieval for Applications) is a three-year project supported by the European Union in the frame of its H2020 Call (EO-2-2015) for “Stimulating wider research use of Copernicus Sentinel Data”. The project addresses key scientific issues relevant for synergistic exploitation of data acquired in different spectral ranges by different instruments on board the atmospheric Sentinels. A novel approach, based on the assimilation of geosynchronous equatorial orbit (GEO) and low Earth orbit (LEO) fused products by application of an innovative algorithm to Sentinel-4 (S-4) and Sentinel-5 (S-5) synthetic data, is adopted to assess the quality of the unique ozone vertical profile obtained in a context simulating the operational environment. The first priority is then attributed to the lower atmosphere with calculation of tropospheric columns and ultraviolet (UV) surface radiation from the resulting ozone vertical distribution. Here we provide details on the surface UV algorithm of AURORA. Both UV index (UVI) and UV-A irradiance are provided from synthetic satellite measurements, which in turn are based on atmospheric scenarios from MERRA-2 (Modern-Era Retrospective analysis for Research and Applications, Version 2) re-analysis. The UV algorithm is implemented in a software tool integrated in the technological infrastructure developed in the context of AURORA for the management of the synthetic data and for supporting the data processing. This was closely linked to the application-oriented activities of the project, aimed to improve the performance and functionality of a downstream application for personal UV dosimetry based on satellite data. The use of synthetic measurements from MERRA-2 gives us also a “ground truth”, against which to evaluate the performance of our UV model with varying inputs. In this study we both describe the UV algorithm itself and assess the influence that changes in ozone profiles, due to the fusion and assimilation, can cause in surface UV levels.


1998 ◽  
Vol 6 (1) ◽  
pp. 7-23 ◽  
Author(s):  
Paul J. Crutzen

Atmospheric ozone plays a critical role in controlling ultraviolet radiation levels at the surface of the Earth. The absorption of ultraviolet radiation from the sun and the warm infrared from the earth influence temperatures in the lower stratosphere. The concentration of ozone is affected by NO, NO2, Cl, and Clo in a complex manner.


2009 ◽  
Vol 47 (6) ◽  
pp. 466-479 ◽  
Author(s):  
O. M. Belotserkovskii ◽  
I. V. Mingalev ◽  
V. S. Mingalev ◽  
O. V. Mingalev ◽  
A. M. Oparin ◽  
...  

1990 ◽  
Vol 14 (2) ◽  
pp. 178-198 ◽  
Author(s):  
C.J.C. Reason ◽  
D.G. Steyn

The dynamics of coastally trapped disturbances in the lower atmosphere are considered. These disturbances are trapped by the existence of a subsidence inversion at a height below the crests of barrier-like coastal mountains and propagate alongshore with the coast on the right (left) in the Northern (Southern) Hemisphere. Favourable areas on the Earth for the existence of the disturbances are California, southeastern Australia and southern Africa. It is shown that the fundamental dynamics of the disturbances is in each case governed by the hydrostatic and semigeostrophic approximations. The latter implies that a geostrophic balance exists between the alongshore velocity of the motion and the across-shore pressure gradient. Although the fundamental dynamics are identical, it is shown that regional differences in forcing and boundary conditions lead to the observed diversity in the manifestation of the disturbances in each area. These differences include variations in the width of the coastal mountains, the strength and height of the inversion, in the scale of the forcing and whether this forcing leads to on- or offshore flow in the generation region of the disturbance.


Hadmérnök ◽  
2019 ◽  
Vol 14 (1) ◽  
pp. 99-107
Author(s):  
László Földi ◽  
László Halász

Defining the term of climate, we investigate the role of natural causes and effects of human activities in climate change. The temperature of the Earth is determined by the balance between the amount of radiation energy received from the Sun and that emitted from the surface of the Earth towards the outer space. Greenhouse gases in the atmosphere, including water vapor, carbon dioxide, methane and nitrous oxides, act to make the surface much warmer, because they absorb and emit heat energy in all directions (including downwards), keeping Earth’s surface and lower atmosphere warm. The primary cause of climate change is the burning of fossil fuels, such as oil and coal, which emits greenhouse gases into the atmosphere – primarily carbon dioxide. We give a review about the activity of the Intergovernmental Panel on Climate Change and the United Nations Climate Change Conferences. Shortly investigate the different global climate models and some regional climate models. Finally discuss the results of regional climate model simulations for the Carpathian Basin.


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