doi:10.1007/s00376-016-5201-4

Anderson G. P., S. A. Clough, F. X. Kneizys, J. H. Chetwynd, and E. P. Shettle, 1986: AFGL atmospheric constituent profiles (0.120km). Tech. Rep. AFGL-TR-86-0110, Air Force Geophysics Lab., Hanscom Air Force Base, Bedford, Mass.

c65e094bb5eba0ad1e04f85da92d08e6

http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F1986aacp.book.....a

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Antõn M., A. Serradno M. L., Cancillo, and J. A. García, 2009: An empirical model to estimate ultraviolet erythemal transmissivity. Ann. Geophys., 27, 1387- 1398.10.5194/angeo-27-1387-2009

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http://onlinelibrary.wiley.com/resolve/reference/XREF?id=10.5194/angeo-27-1387-2009An empirical model to estimate the solar ultraviolet erythemal irradiance (UVER) for all-weather conditions is presented. This model proposes a power expression with the UV transmissivity as a dependent variable, and the slant ozone column and the clearness index as independent variables. The UVER were measured at three stations in South-Western Spain during a five year period (2001-2005). A dataset corresponding to the period 2001-2004 was used to develop the model and an independent dataset (year 2005) for validation purposes. For all three locations, the empirical model explains more than 95% of UV transmissivity variability due to changes in the two independent variables. In addition, the coefficients of the models show that when the slant ozone amount decreases 1%, UV transmissivity and, therefore, UVER values increase approximately 1.33%-1.35%. The coefficients also show that when the clearness index decreases 1%, UV transmissivity increase 0.75%-0.78%. The validation of the model provided satisfactory results, with low mean absolute bias error (MABE), about 7%-8% for all stations. Finally, a one-day ahead forecast of the UV Index for cloud-free cases is presented, assuming the persistence in the total ozone column. The percentage of days with differences between forecast and experimental UVI lower than 0.5 unit and 1 unit is within the range of 28% to 37%, and 60% to 75%, respectively. Therefore, the empirical model proposed in this work provides reliable forecast cloud-free UVI in order to inform the public about the possible harmful effects of UV radiation over-exposure.

Bilbao J., R. Román C. Yousif, D. Mateos, and A. de Miguel, 2014: Total ozone column, water vapour and aerosol effects on erythemal and global solar irradiance in Marsaxlokk, Malta. Atmos. Environ., 99, 508- 518.10.1016/j.atmosenv.2014.10.005

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http%3A%2F%2Fwww.sciencedirect.com%2Fscience%2Farticle%2Fpii%2FS1352231014007821

http://www.sciencedirect.com/science/article/pii/S1352231014007821Observations of erythemal (UVER; 280–400nm) and total solar shortwave irradiance (SW; 305–2800nm), total ozone column (TOC), water vapour column (w), aerosol optical depth (AOD) and 03ngstr02m exponent (α) were carried out at Marsaxlokk, in south-east Malta. These measurements were recorded during a measurement campaign between May and October 2012, aimed at studying the influence of atmospheric compounds on solar radiation transfer through the atmosphere. The effects of TOC, AOD andon UVER and SW (global, diffuse and direct) irradiance were quantified using irradiance values under cloud-free conditions at different fixed solar zenith angles (SZA). Results show that UVER (but not SW) irradiance correlates well with TOC. UVER variations ranged between610.24%DUand610.32%DUwith all changes being statistically significant. Global SW irradiance varies with water vapour column between612.44%cmand614.53%cm, these results proving statistically significant and diminishing when SZA increases. The irradiance variations range between 42.15%cmand 20.30%cmfor diffuse SW when SZA varies between 20° and 70°. The effect of aerosols on global UVER is stronger than on global SW. Aerosols cause a UVER reduction of between 28.12% and 52.41% and a global SW reduction between 13.46% and 41.41% per AOD550 unit. Empirical results show that solar position plays a determinant role, that there is a negligible effect of ozone on SW radiation, and stronger attenuation by aerosol particles in UVER radiation.

Burrows W. R., 1997: CART regression models for predicting UV radiation at the ground in the presence of cloud and other environmental factors. J. Appl. Meteor., 36( 5), 531- 544.10.1175/1520-0450(1997)036<0531:CRMFPU>2.0.CO;2

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http%3A%2F%2Fadsabs.harvard.edu%2Fabs%2F1997JApMe..36..531B

http://adsabs.harvard.edu/abs/1997JApMe..36..531BThe goal was to build models for predicting ground-level biologically weighted ultraviolet radiation (UV index, shortened to UV here) that would not require substantial execution time in weather and climate models and yet be reasonably accurate. Recent advances in modeling data make this goal possible. UV data computed from Brewer spectrophotometer measurements at Toronto were matched with observed meteorological predictors for 1989-93. Data were stratified into three sets by solar zenith angle 70 and time between 1000 and 1400 LST. Stepwise linear regression (SLR) and CART (nonlinear) tree-based regression models were built for UV and N(UV) (ratio: observed UV to clear-sky UV). CART models required fewer predictors to achieve minimum error, and that minimum was lower than SLR. For zenith angle less than 70 CART regression models were superior to SLR by 5%-10% error after regression. The CART model had 31% relative error (ratio: estimated mean-squared error after regression to sample variance) and three predictors: total opacity, liquid precipitation, and snow cover. Including five next predictors decreased error only another 1%. For zenith angle 70 or greater, SLR could not produce a useful model, whereas CART gave a model with 15% relative error using three predictors. Total opacity is by far the most important predictor throughout. Snow cover enhances UV at the ground by 11%-13% even in cloudy conditions, but its relative influence decreases with zenith angle. For general use at other locations models with as few predictors as possible are desirable. CART models with 34%-35% relative error were built with three predictors: total opacity, zenith angle, and clear-sky UV. Tests were done at 11 stations for several months in 1995. Averaged root-mean-squared discrepancy between predicted and observed UV is reduced about 40% when observed opacity is used for the CART prediction compared to using clear-sky UV. When an 18-h forecast opacity is used the reduction is about 25%. Improvement over clear-sky UV is substantially greater than this on cloudy days. Thus, CART three-predictor models for N(UV) can be used poleward of Toronto in a variety of cloud conditions in analysis or forecast modes. A predictor representing smoke from forest fires was not included. Several cases during the test period showed clear-sky UV was reduced by smoke 30%-50% near to the fires and 20%-30% far downwind.

Calb贸, J., D. Pag\`es, J. A. González, 2005: Empirical studies of cloud effects on UV radiation: A review. Rev. Geophys.,43(2), doi: 10.1029/2004RG000155.10.1029/2004RG000155

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2004RG000155%2Fabstract

http://onlinelibrary.wiley.com/doi/10.1029/2004RG000155/abstract[1] The interest in solar ultraviolet (UV) radiation from the scientific community and the general population has risen significantly in recent years because of the link between increased UV levels at the Earth's surface and depletion of ozone in the stratosphere. As a consequence of recent research, UV radiation climatologies have been developed, and effects of some atmospheric constituents (such as ozone or aerosols) have been studied broadly. Correspondingly, there are well-established relationships between, for example, total ozone column and UV radiation levels at the Earth's surface. Effects of clouds, however, are not so well described, given the intrinsic difficulties in properly describing cloud characteristics. Nevertheless, the effect of clouds cannot be neglected, and the variability that clouds induce on UV radiation is particularly significant when short timescales are involved. In this review we show, summarize, and compare several works that deal with the effect of clouds on UV radiation. Specifically, works reviewed here approach the issue from the empirical point of view: Some relationship between measured UV radiation in cloudy conditions and cloud-related information is given in each work. Basically, there are two groups of methods: techniques that are based on observations of cloudiness (either from human observers or by using devices such as sky cameras) and techniques that use measurements of broadband solar radiation as a surrogate for cloud observations. Some techniques combine both types of information. Comparison of results from different works is addressed through using the cloud modification factor (CMF) defined as the ratio between measured UV radiation in a cloudy sky and calculated radiation for a cloudless sky. Typical CMF values for overcast skies range from 0.3 to 0.7, depending both on cloud type and characteristics. Despite this large dispersion of values corresponding to the same cloud cover, it is clear that the cloud effect on UV radiation is 15-45% lower than the cloud effect on total solar radiation. The cloud effect is usually a reducing effect, but a significant number of works report an enhancement effect (that is increased UV radiation levels at the surface) due to the presence of clouds. The review concludes with some recommendations for future studies aimed to further analyze the cloud effects on UV radiation.

Caldwell M. M., L. O. Björn, J. F. Bornman, S. D. Flint, G. Kuland aivelu, A. H. Teramura, and M. Tevini, 1998: Effects of increased solar ultraviolet radiation on terrestrial ecosystems. Journal of Photochemistry and Photobiology B: Biology, 46( 1-3), 40- 52.10.1016/S1011-1344(98)00184-5

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http%3A%2F%2Fwww.sciencedirect.com%2Fscience%2Farticle%2Fpii%2FS1011134498001845

http://www.sciencedirect.com/science/article/pii/S1011134498001845Elevated solar UV-B radiation associated with stratospheric ozone reduction may exert effects on terrestrial ecosystems through actions on plants, microbes, and perhaps on some animals. At the ecosystem level, the effects are less well understood than at the molecular and organismal levels. Many of the most important, yet less predictable, consequences will be indirect effects of elevated UV-B acting through changes in the chemical composition and form of plants and through changes in the abiotic environment. These indirect effects include changes in the susceptibility of plants to attack by insects and pathogens in both agricultural and natural ecosystems; the direction of these changes can result in either a decrease or an increase in susceptibility. Other indirect effects of elevated UV-B include changes in competitive balance of plants and nutrient cycling. The direct UV-B action on plants that results in changes in form or function of plants appears to occur more often through altered gene activity rather than damage. The yield of some crop varieties can be decreased by elevated UV-B, but other varieties are not affected. Plant breeding and genetic engineering efforts should be able to cope with the potential threats to crop productivity due to elevated UV-B. For forest trees, this may be more difficult if effects of elevated UV-B accumulate over several years. All effects of elevated UV-B radiation must be considered in the context of other climate changes such as increased temperature and levels of carbon dioxide, which may alter the UV-B responses, especially for plants. The actions of elevated carbon dioxide and UV-B appear to be largely independent, but interactions occur between changes in UV-B and other factors. Other ecosystem-level consequences of elevated UV-B radiation are emerging and their magnitude and direction will not be easily predicted.

Casale G. R., D. Meloni, S. Miano, S. Palmieri, A. M. Siani, and F. Cappellani, 2000: Solar UV-B irradiance and total ozone in Italy: Fluctuations and trends. J. Geophys. Res., 105( D4), 4895- 4901.10.1029/1999JD900303

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http://onlinelibrary.wiley.com/doi/10.1029/1999JD900303/fullSolar UV irradiance spectra (290-325 nm) together with daily total ozone column observations have been collected since 1992 by means of Brewer spectrophotometers at two Italian stations (Rome and Ispra). The available Brewer irradiance data, recorded around noon and at fixed solar zenith angles, together with the output of a radiative transfer model (the STAR model) are presented and analyzed. The Brewer irradiance measurements and total ozone fluctuations and anomalies are investigated, pointing out the correlation between the high-frequency O 3 components and irradiance at 305 nm. In addition, the total ozone long time series of Arosa (170 km apart from Ispra) and Vigna di Valle (very close to Rome) are analyzed to illustrate evidence of temporal variations and a possible trend.

den Outer, P. N., H. Slaper, R. B. Tax, 2005: UV radiation in the Netherlands: Assessing long-term variability and trends in relation to ozone and clouds. J. Geophys. Res. , 110,D02203, doi:10.1029/2004JD004824.10.1029/2004JD004824

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http://onlinelibrary.wiley.com/doi/10.1029/2004JD004824/pdf[1] The variability and long-term changes in the ultraviolet (UV) climate in the Netherlands have been studied in relation to ozone and clouds, by analyzing modeled and measured values for daily, monthly, and yearly integrated erythemally weighted UV doses. At Bilthoven, Netherlands (longitude 5.19°E, latitude 52.12°N), UV irradiance measurements for the 1994–2003 period yielded a mean annual dose of 447 ± 29 kJ/m 2 and a mean daily dose of 2.5 ± 0.5 kJ/m 2 for June and July. On average, the maximum UV index exceeded 6.5 (i.e., 0.1625 W/m 2 erythemally weighted) on 10 days per year (21 days in 2003). The mean value of measured-to-modeled ratios of erythemal UV irradiances was 1.00 with a standard deviation of 0.06 for days when the measured global solar radiation agrees within 5% with the cloudless sky value. Three previously introduced approaches to model cloud effects on UV doses were shown to have limitations when applied for low Sun and/or optically thick clouds, while a new approach provided the most consistent results with an average ratio of the measured-to-modeled daily doses of 1.02 and a standard deviation of 0.09, for all seasons and weather conditions for the period 1994–2002. Further analysis also revealed a wavelength dependency of the correlation between global solar radiation and UV radiation. Clouds, on average, reduced the daily dose of erythemal UV to 68% of the clear-sky value, whereas for global solar radiation this was 57%. The modeled annual erythemal UV dose was 622 kJ/m 2 (402 kJ/m 2 ) averaged over the years 1979–1982, while the years 2000–2003 yield 662 kJ/m 2 (448 kJ/m 2 ) for cloudless (cloudy) conditions. In the past 25 years the highest annual doses were received in 1995 (485 kJ/m 2 ) and 2003 (488 kJ/m 2 ): in 1995 as a result of extremely low ozone values and moderate cloud reduction and in 2003 as a result of extremely low cloud reduction combined with moderately low ozone values. As an indication of the changes over time, a linear regression is performed showing that the annual UV dose received at the ground for all weather conditions increased with 5.5 ± 2% per decade for erythemal UV over the 1979–2003 period.

Fioletov V. E., L. J. B. McArthur, J. B. Kerr, and D. I. Wardle, 2001: Long-term variations of UV-B irradiance over Canada estimated from Brewer observations and derived from ozone and pyranometer measurements. J. Geophys. Res., 106( D19), 23009- 23027.10.1029/2001JD000367

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http://onlinelibrary.wiley.com/doi/10.1029/2001JD000367/fullRoutine uniform spectral UV-B measurements with Brewer spectrophotometers in the Canadian network began in 1989. This relatively short duration of UV measurements militates against reliable detection of long-term changes in UV. A statistical model has been developed to extend the record of UV back to the early 1960s. It estimates UV values (at individual wavelengths and spectrally integrated) from global solar radiation, total ozone, dew point temperature, and snow cover. The model results are demonstrated to be in good agreement with the measurements. For example, the standard deviation of the difference between monthly values of measured and derived erythemally weighted UV irradiation is 3.3% for summer months. The major source of error in the model estimates is probably linked to rare occurrences of absorbing aerosols in the atmosphere. Long records of reliable measurements of total ozone, global solar radiation, and other parameters made it possible to derive UV-B values at three Canadian stations from the mid-1960s. Trends in derived erythemally weighted UV at two stations (Toronto and Edmonton) are similar to those expected from total ozone trends although the estimated error of the UV trends is more than 2 times larger. However, the increase in annual UV at Churchill (59N) in 1979-1997 was found to be more than twice that expected from the ozone decline. This is a result of longterm changes in snow cover and clouds.

Kaurola J., P. Taalas, T. Koskela, J. Borkowski, and W. Josefsson, 2000: Long-term variations of UV-B doses at three stations in northern Europe. J. Geophys. Res., 105( D16), 20813- 20820.10.1029/2000JD900258

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F2000JD900258%2Ffull

http://onlinelibrary.wiley.com/doi/10.1029/2000JD900258/fullRecent analysis of the total ozone observations indicate a negative trend of about 4%/decade in the Northern Hemisphere midlatitudes during the last two decades [WMO, 1999]. The effect of this decline on surface UV levels is of interest to a variety of applications. In this work the long-term variation of UV radiation at three stations located in northern Europe (Belsk, Norrk枚ping, and Jokioinen) has been studied using data from (1) ground-based observations, (2) surface UV doses determined using TOMS satellite measurements, and (3) reconstructed UV doses using observations of global radiation, total ozone, and radiative transfer modeling. For each station the estimates of daily UV doses from various sources have been intercompared, and a trend analysis has been performed to reveal long-term changes in the UV radiation. Data sets, which start in the late 1970s or early 1980s, show a general positive trend in annual doses of UV radiation. Some of these upward trends are statistically significant. For Belsk the increases are in the range of 5-15% per decade during spring and summer. The largest increases, about 20%/decade, has been observed in Norrk枚ping during spring. At Jokioinen there has been a slight upward trend in UV throughout the year. The analysis of reconstructed Belsk data from 1966 onward shows that the positive trend since late 1970s was preceeded by a negative trend. The reason for such changes is probably not only related to the changes in the total ozone but also to changes in aerosol content and cloudiness. The agreement of the UV series based on different data sources is good. This was studied using a subset of data in which it was required that data from all possible sources were available. The different trend estimates were in very close agreement with each other. However, there were often differences in absolute values, which is probably related to problems in calibration and limitations of the models.

Kim J., H. K. Cho, J. Mok, H. D. Yoo., and N. Cho, 2013: Effects of ozone and aerosol on surface UV radiation variability. Journal of Photochemistry and Photobiology B: Biology, 119, 46- 51.10.1016/j.jphotobiol.2012.11.007

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1f9641870c3396d34e24fa28812bf2ec

http%3A%2F%2Fwww.sciencedirect.com%2Fscience%2Farticle%2Fpii%2FS1011134412002515

http://www.sciencedirect.com/science/article/pii/S1011134412002515Abstract Global (direct+diffuse) spectral ultraviolet (UV, 290-363nm) and total ozone measurements made on the roof of the Main Science Building, Yonsei University at Seoul (37.57°, 128.98°E) were analyzed to quantify the effects of ozone and aerosol on the variability of surface erythemal UV (EUV) irradiance. The measurements have been made with a Brewer Spectrophotometer MKIV (SCI-TEC#148) and a Dobson Ozone Spectrophotometer (Beck#123), respectively, during 2004-2008. The overall mean radiation amplification factor, RAF(AOD, SZA) [23,24] due to total ozone (O(3)) (hereafter O(3) RAF) shows that 1% decrease in total ozone results in an increase of 1.18±0.02% in the EUV irradiance with the range of 0.67-1.74% depending on solar zenith angles (SZAs) (40-70°) and on aerosol optical depths (AODs) (<4.0), under both clear (cloud cover<25%) and all sky conditions. For the mean AOD, the O(3) RAFs(SZA) for both sky conditions increased as SZA increased from 40° to 60°, and then decreased for higher SZA 70°, where the patterns are consistent with results of the previous studies [2,10]. A similar analysis of the RAF(O(3), SZA) due to AOD (hereafter AOD RAF) under clear and all-sky conditions shows that on average, a 1% increase in AOD forces a decrease of 0.29±0.06% in the EUV irradiance with the maximum range 0.18-0.63% depending on SZAs and O(3). Thus, overall sensitivity of UV to ozone (O(3), RAF) was estimated to be about four times higher than to the aerosol (AOD RAF). At the mean O(3), the AOD RAFs(SZA) for both skies appears to be almost independent of SZAs. It is shown that the O(3) RAFs are nearly independent of the sky conditions, whereas the AOD RAFs depend distinctly on the sky conditions with the larger values for all skies. Under cloud free conditions, the overall mean ratio for measured-to-modeled O(3), RAF(AOD, SZA) is 1.13, whereas the ratio for AOD RAF(O(3), SZA) shows 0.82 in the EUV irradiance. Overall, the RAF measurements are corroborated by radiative transfer model calculations under clear-sky conditions. Copyright 08 2012 Elsevier B.V. All rights reserved.

Lee Y. G., J. Kim, H.-K. Cho, B. C. Choi, J. Kim, S. R. Chung, and I. S. Park, 2008: Forecast of UV-index over Korea with improved total ozone prediction and effects of aerosol, clouds and surface albedo. Asia-Pacific J. Atmos. Sci., 44( 4), 381- 400.

Lee Y. G., J.-H. Koo, and J. Kim, 2015: Influence of cloud fraction and snow cover to the variation of surface UV radiation at King Sejong station, Antarctica. Atmos. Res., 164-165, 99- 109.10.1016/j.atmosres.2015.04.020

f65ba53ca07ce1e35af12bf29895b6b4

http%3A%2F%2Fwww.sciencedirect.com%2Fscience%2Farticle%2Fpii%2FS0169809515001374

http://www.sciencedirect.com/science/article/pii/S0169809515001374This study investigated how cloud fraction and snow cover affect the variation of surface ultraviolet (UV) radiation by using surface Erythemal UV (EUV) and Near UV (NUV) observed at the King Sejong Station, Antarctica. First the Radiative Amplification Factor (RAF), the relative change of surface EUV according to the total-column ozone amount, is compared for different cloud fractions and solar zenith angles (SZAs). Generally, all cloudy conditions show the increase of RAF as SZA becomes larger, showing the larger effects of vertical columnar ozone. For given SZA cases, the EUV transmission through mean cloud layer gradually decreases as cloud fraction increases, but sometimes the maximum of surface EUV appears under partly cloudy conditions. The high surface EUV transmittance under broken cloud conditions seems due to the re-radiation of scattered EUV by cloud particles. NUV transmission through mean cloud layer also decreases as cloud amount increases but the sensitivity to the cloud fraction is larger than EUV. Both EUV and NUV radiation at the surface are also enhanced by the snow cover, and their enhancement becomes higher as SZA increases implying the diurnal variation of surface albedo. This effect of snow cover seems large under the overcast sky because of the stronger interaction between snow surface and cloudy sky.

Madronich S., R. L. McKenzie, L. O. Björn, and M. M. Caldwell, 1998: Changes in biologically active ultraviolet radiation reaching the Earth's surface. Journal of Photochemistry and Photobiology B: Biology, 46( 1-3), 5- 19.10.1039/B700017K

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http%3A%2F%2Fwww.sciencedirect.com%2Fscience%2Farticle%2Fpii%2FS1011134498001821

http://med.wanfangdata.com.cn/Paper/Detail/PeriodicalPaper_PM12659535Long-term predictions of future UV-B levels are difficult and uncertain. Nevertheless, current best estimates suggest that a slow recovery to preozone depletion levels may be expected during the next half-century. Although the maximum ozone depletion, and hence maximum UV-B increase, is likely to occur in the current decade, the ozone layer will continue to be in its most vulnerable state into the next century. The peak depletion and the recovery phase could be delayed by decades because of interactions with other long-term atmospheric changes, e.g., increasing concentrations of greenhouse gases. Other factors that could influence the recovery include non-ratification and/or non-compliance with the Montreal Protocol and its Amendments and Adjustments, and future volcanic eruptions. The recovery phase for surface UV-B irradiances will probably not be detectable until many years after the ozone minimum.

Mateos D., J. Bilbao, A. de Miguel, and A. Pèrez-Burgos, 2010: Dependence of ultraviolet (erythemal and total) radiation and CMF values on total and low cloud covers in Central Spain. Atmospheric Research, 98( 1), 21- 27.10.1016/j.atmosres.2010.05.002

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http%3A%2F%2Fwww.sciencedirect.com%2Fscience%2Farticle%2Fpii%2FS0169809510001183

http://www.sciencedirect.com/science/article/pii/S0169809510001183The cloudiness effect on solar ultraviolet radiation (UV) has been analyzed in this study. Measurements of erythemal and UV total radiations have been registered in Valladolid, Central Spain (lat. 41 40'N, long. 4 50'W and 840 m a.s.l.). A statistical analysis of cloudiness has been carried out resulting clear skies (0-2 oktas) the most frequent conditions under low cloud cover, while cloudy skies (6-7 oktas) are the prevailing under total cloud cover. Hence, the dependences of erythemal UV (UVER) and UV total (UVT) radiations and CMF values (on both ranges) on total and low cloud covers have been analyzed. In all cases, low clouds show higher attenuation than total cloud cover. Moreover, an empirical formula proposed by other authors for several Spanish cities is verified with very similar coefficients for Valladolid database. Finally, the dependence of the ratio between CMF values on UVER and UVT radiations on cloud cover and solar elevation angle is analyzed. As a result, UVER and UVT radiations are not affected by the clouds in the same way. Actually, for low solar elevation angles, UVER is not as attenuated as UVT radiation. However, for high ones under cloudy (6-7 oktas) and, particularly, overcast (8 oktas) conditions, UVER presents smaller CMF values and, therefore, a higher attenuation. Due to the different spectral ranges between erythemal and UV total radiations, the photon reflections above the cloud, the Rayleigh scattering and the interaction of UV radiation with atmospheric components like ozone could explain these effects.

Mayer B., A. Kylling, 2005: Technical note: The libRadtran software package for radiative transfer calculationsユ柡锟芥攧escription and examples of use. Atmos. Chem. Phys., 5, 1855- 1877.

Mayer B., G. Seckmeyer, and A. Kylling, 1997: Systematic long-term comparison of spectral UV measurements and UVSPEC modeling results. J. Geophys. Res., 102( D7), 8755- 8767.10.1029/97JD00240

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http://onlinelibrary.wiley.com/doi/10.1029/97JD00240/fullFor the evaluation of radiative transfer models and for investigations on the influence of parameters like aerosols or clouds on ground level UV irradiance, a combination of spectral measurements and model calculations is required. We show an efficient method for such a combination and present a systematic comparison of the freely available UVSPEC radiative transfer model package with two years of spectrally resolved measurements made at Garmisch-Partenkirchen, Germany (47.48°N, 11.07°E, 730 m above sea level) for cloudless sky and low albedo. More than 1200 spectra have been used for the comparison, covering a wide range of ozone and aerosol conditions. Applying the PSEUDO-SPHERICAL model type, a discrete ordinate model with correction for the sphericity of the Earth, the systematic differences between measurement and model were found to range between 6111 and +2% for wavelengths between 295 and 400 nm and solar zenith angles up to 80°. The small observed statistical differences of 2–3% can mostly be explained by the random error of the measurement system. Only two input parameters, total ozone column and aerosol optical depth, the latter parameterized by the Angstrom formula, are required to reach this level of agreement. It was further found that knowledge of the aerosol optical depth is essential for obtaining such a good agreement. The evaluated UVSPEC model package, together with the presented interface SDMODEL, provides an efficient tool for the investigation of the processes that control surface UV irradiance.

McKinlay A. F., B. L. Diffey, 1987: A reference action spectrum for ultra-violet induced erythema in human skin. Human Exposure to Ultraviolet Radiation: Risks and Regulations, W. F. Passchier and B. F. M. Bosnajakovic, Eds., Elsevier, 83- 87.10.1111/j.1600-0749.1990.tb00331.x

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http://onlinelibrary.wiley.com/resolve/reference/PMED?id=2203439Although the sun remains the main source of ultraviolet radiation (UVR) exposure in , the advent of artificial UVR sources has increased the opportunity for both intentional and unintentional exposure. Intentional exposure is most often to tan the skin. People living in less sunny climates can now maintain a year-round tan by using sunbeds and emitting principally UVA radiation. Another reason for intentional exposure to artificial UVR is treatment of , notably . Unintentional exposure is normally the result of occupation. Outdoor workers, such as farmers, receive three to four times the annual solar UV exposure of indoor workers. Workers in many industries, eg, photoprinting or hospital phototherapy departments, may be exposed to UVR from artificial sources. One group particularly at risk is electric arc welders, where inadvertent exposure is so common that the terms "" or "welders flash" are often used to describe . In addition to unavoidable exposure to natural UVR, the general public is exposed to low levels of UVR from sources such as fluorescent lamps used for indoor lighting and shops and restaurants where UVA lamps are often used in traps to attract flying .

McKenzie R. L., W. A. Matthews, and P. V. Johnston, 1991: The relationship between erythemal UV and ozone, derived from spectral irradiance measurements. Geophys. Res. Lett., 18( 12), 2269- 2272.10.1029/91GL02786

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http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1029%2F91GL02786%2Fabstract

http://onlinelibrary.wiley.com/doi/10.1029/91GL02786/abstractSpectral measurements of solar ultraviolet (UV) radiation received at the ground at Lauder, New Zealand (45°S) during 1990 are used in conjunction with ozone total column measurements to investigate the relative importance to erythemally active UV radiation of variations in solar zenith angle, ozone, and cloud cover. At this site solar zenith angle variations are the dominant factor, but clouds frequently attenuate the clear sky irradiances by more than 50%. Ozone reductions of 1% typically cause an increase in erythemally active UV irradiance of 1.25±0.20%.

McKenzie R. L., P. J. Aucamp, A. F. Bais, L. O. Björn, M. Ilyas, and S. Madronich, 2011: Ozone depletion and climate change: impacts on UV radiation. Photochemical & Photobiological Sciences, 10( 2), 182- 198.10.1039/c0pp90034f

21253660

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http://med.wanfangdata.com.cn/Paper/Detail/PeriodicalPaper_PM21253660The Montreal Protocol is working, but it will take several decades for ozone to return to 1980 levels. The atmospheric concentrations of ozone depleting substances are decreasing, and ozone column amounts are no longer decreasing. Mid-latitude ozone is expected to return to 1980 levels before mid-century, slightly earlier than predicted previously. However, the recovery rate will be slower at high latitudes. Springtime ozone depletion is expected to continue to occur at polar latitudes, especially in Antarctica, in the next few decades. Because of the success of the Protocol, increases in UV-B radiation have been small outside regions affected by the Antarctic ozone hole, and have been difficult to detect. There is a large variability in UV-B radiation due to factors other than ozone, such as clouds and aerosols. There are few long-term measurements available to confirm the increases that would have occurred as a result of ozone depletion. At mid-latitudes UV-B irradiances are currently only slightly greater than in 1980 (increases less than ~5%), but increases have been substantial at high and polar latitudes where ozone depletion has been larger. Without the Montreal Protocol, peak values of sunburning UV radiation could have been tripled by 2065 at mid-northern latitudes. This would have had serious consequences for the environment and for human health. There are strong interactions between ozone depletion and changes in climate induced by increasing greenhouse gases (GHGs). Ozone depletion affects climate, and climate change affects ozone. The successful implementation of the Montreal Protocol has had a marked effect on climate change. The calculated reduction in radiative forcing due to the phase-out of chlorofluorocarbons (CFCs) far exceeds that from the measures taken under the Kyoto protocol for the reduction of GHGs. Thus the phase-out of CFCs is currently tending to counteract the increases in surface temperature due to increased GHGs. The amount of stratospheric ozone can also be affected by the increases in the concentration of GHGs, which lead to decreased temperatures in the stratosphere and accelerated circulation patterns. These changes tend to decrease total ozone in the tropics and increase total ozone at mid and high latitudes. Changes in circulation induced by changes in ozone can also affect patterns of surface wind and rainfall. The projected changes in ozone and clouds may lead to large decreases in UV at high latitudes, where UV is already low; and to small increases at low latitudes, where it is already high. This could have important implications for health and ecosystems. Compared to 1980, UV-B irradiance towards the end of the 21st century is projected to be lower at mid to high latitudes by between 5 and 20% respectively, and higher by 2-3% in the low latitudes. However, these projections must be treated with caution because they also depend strongly on changes in cloud cover, air pollutants, and aerosols, all of which are influenced by climate change, and their future is uncertain. Strong interactions between ozone depletion and climate change and uncertainties in the measurements and models limit our confidence in predicting the future UV radiation. It is therefore important to improve our understanding of the processes involved, and to continue monitoring ozone and surface UV spectral irradiances both from the surface and from satellites so we can respond to unexpected changes in the future.

Molina L. T., M. J. Molina, 1986: Absolute absorption cross sections of ozone in the 185- to 350-nm wavelength range. J. Geophys. Res., 91( D13), 14501- 14508.10.1029/JD091iD13p14501

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http://onlinelibrary.wiley.com/doi/10.1029/JD091iD13p14501/fullThe absorption cross sections of ozone have been measured in the wavelength range 185-350 nm and in the temperature range 225-298 K. The absolute ozone concentrations were established by measuring the pressure of pure gaseous samples in the 0.08to 300-torr range, and the UV spectra were recorded under conditions where less than 1 percent of the sample decomposed. The temperature dependence is significant for wavelengths longer than about 280 nm. The absorption cross-section values around 210 nm were found to be about 10 percent larger than the previously accepted values.

Nichol S. E., G. Pfister, G. E. Bodeker, R. L. McKenzie, S. W. Wood, and G. Bernhard, 2003: Moderation of cloud reduction of UV in the Antarctic due to high surface albedo. J. Appl. Meteor., 42, 1174- 1183.10.1175/1520-0450(2003)042<1174:MOCROU>2.0.CO;2

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http://adsabs.harvard.edu/abs/2003JApMe..42.1174NTo gauge the impact of clouds on erythemal (sunburn causing) UV irradiances under different surface albedo conditions, UV measurements from two Antarctic sites (McMurdo and South Pole Stations) and a midlatitude site (Lauder, New Zealand) are examined. The surface albedo at South Pole remains high throughout the year, at McMurdo it has a strong annual cycle, and at Lauder it is low throughout the year. The measurements at each site are divided into clear and cloudy subsets and are compared with modeled clear-sky irradiances to assess the attenuation of UV by clouds. A radiative transfer model is also used to interpret the observations. Results show increasing attenuation of UV with increasing cloud optical depth, but a high surface albedo can moderate this attenuation as a result of multiple scattering between the surface and cloud base. This effect is of particular importance at high latitudes where snow may be present during the summer months. There is also a tendency toward greater cloud attenuation with increasing solar zenith angle.

Park S. S., Y. G. Lee, and J. H. Kim, 2015: Impact of UV-A radiation on erythemal UV and UV-index estimation over Korea. Adv. Atmos. Sci.,32(12), 1639-1646, doi: 10.1007/s00376-015-4231-7.10.1007/s00376-015-4231-7

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http://d.wanfangdata.com.cn/Periodical/dqkxjz-e201512007Because total UV(TUV) in the UV-A region is 100 times higher than in the UV-B region,UV-A is a considerable component when calculating erythemal UV(EUV) and UV-index.The ratio of EUV to TUV in the UV-A value [EUV(A)/TUV(A)]is investigated to convert the EUV(A) from TUV(A) for broadband observation. The representative value of EUV(A)/TUV(A),from the simulation study,is 6.9 × 10-4,changing from 6.1 × 10-4to 7.0 × 10-4as aerosol optical depth,total ozone and solar zenith angle change. By adopting the observational data of EUV(B) and TUV(A) from UV-biometer measurements at Yonsei University [(37.57?N,126.95?E),84 m above sea level],the EUV irradiance increases to 15% of EUV(B) due to the consideration of EUV(A) from the data of TUV(A) observation. Compared to the total EUV observed from the Brewer spectrophotometer at the same site,the EUV(B) from the UV-biometer observes only 95% of total EUV,and its underestimation is caused by neglecting the effect of UV-A. However,the sum of EUV(B) and EUV(A) [EUV(A+B)] from two UV-biometers is 10% larger than the EUV from the Brewer spectrophotometer because of the spectral overlap effect in the range 320–340nm. The correction factor for the overlap effect adjusts 8% of total EUV.

Setlow R. B., 1974: The wavelengths in sunlight effective in producing skin cancer: A theoretical analysis. Proceedings of the National Academy of Sciences of the United States of America, 71( 9), 3363- 3366.3289990179105261466058562922232222453030889447026434289264539

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http://mutage.oxfordjournals.org/cgi/ijlink?linkType=ABST&journalCode=pnas&resid=71/9/3363

Shettle E. P., 1989: Models of aerosols, clouds, and precipitation for atmospheric propagation studies. Paper Presented at Conference on Atmospheric Propagation in the UV, Visible, IR, and MM-Wave Region and Related Systems Aspects, NATO Adv. Group for Aerosp. Res. and Dev.,Copenhagen.

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http://citeseer.uark.edu:8080/citeseerx/showciting;jsessionid=25948DFBF9D166B41B6397E8447B8A58?cid=7069289CiteSeerX - Scientific documents that cite the following paper: Models of aerosols, clouds and precipitation for atmospheric propagation studies, in: Atmospheric propagation in the uv, visible, ir and mm-region and related system aspects, no

Smith R. C., Z. M. Wan, and K. S. Baker, 1992: Ozone depletion in Antarctica: Modeling its effect on solar UV irradiance under clear-sky conditions. J. Geophys. Res., 97( C5), 7383- 7397.10.1029/92JC00023

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refpaperuri:(fc923e2aa30f8d431bdd801982f031f1)

http://onlinelibrary.wiley.com/doi/10.1029/92JC00023/pdfThe quantitative evaluation of ozone depletion and the related increase in UV irradiation is studied analytically by developing a model based on radiative-transfer simulations. A theoretical simulation of spectroradiometer surface data is advanced that can be used to extrapolate the data over time and space. Calculated UV irradiance and surface-measurement UV data are analyzed as functions of variance in total column ozone, surface albedo, and solar zenith angle. Attention is given to the differences in ozone values estimated with TOMS data vs other UV spectroradiometer data. Good agreement is found in the UV region, and UV irradiance-ratio and UV-B estimation methods are proposed for these datasets. The present models permit the effective estimation of UV-B/UV-A/photosynthetic-available-radiation ratios which are of use in the study of ozone depletion over the Antarctic.

Seckmeyer G., A. Bais, G. Bernhard, M. Blumthaler, B. Johnsen, K. Lantz, and R. McKenzie, 2010a: Instruments to measure solar ultraviolet radiation part 3: Multi-channel filter instruments,Technical Report No. 190, WMO/TD-No. 1537, WMO, Global Atmospheric Watch, 55 pp.

Seckmeyer G., A. Bais, M. Blumthaler, S. Drüke P. Kiedron, K. Lantz, R. McKenzie, and S. Riechelmann, 2010b: Instruments to measure solar ultraviolet radiation part 4: Array Spectraoradiometers,Technical Report No. 191, WMO/TD-No. 1538, WMO, Global Atmospheric Watch, 43 pp.