Measurements Of Solar Ultraviolet Radiation Research Articles

Smart City and the digital measurement of solar ultraviolet radiation in Outdoor workers in the City of Lisbon

Abstract The growing incidence of skin cancer over the years has made it a significant public health problem. However, technology can be used to tackle the skin cancer which is highly preventable, mainly through reduced exposure to solar ultraviolet radiation (UVR). Digital services can be used to promote individual and collective protective measures and interventions. Specifically, there is an opportunity when the exposure is intermittent or continuous, and occurs in an occupational or leisure setting. We are using a digital platform to contribute to raising public and policy awareness on solar UVR-inflicted occupational skin cancers in the municipality of Lisbon. The digital platform is performing direct measurements of the solar UVR dose received by outdoor workers. Results will likely contribute to further understanding the risk estimates for keratinocyte cancer estimations in this population. The digital platform integrates a personal electronic dosimeter (GENESIS-UV system) to assess occupational solar UVR doses of gardeners, masons, and gravediggers of the municipality of Lisbon. Two hundred and ten outdoor workers were selected to wear the dosimeter for 1 month each, between April and October during their daily working hours. The digital platform that offers private access to information through dashboard visualization provided information for the outdoor workers and facilitate communication with the participants. Study data provides the outdoor workers with information on their personal solar UVR exposure during their working hours and an estimate of their risk of developing skin cancer. The results prospectively should flow into the design of adequate prevention campaigns for skin cancer in outdoor workers.

Development of a Low-Cost Device for Measuring Ultraviolet Solar Radiation

Accurate measurements of solar ultraviolet radiation are needed for air quality monitoring, especially to understand the formation and photolysis of tropospheric ozone near the ground. It is interesting to investigate whether this demand could be met using recently developed low-cost UV sensors and new communication technologies. Despite the promising possibilities, their use is still scarce and their potential applications have not yet been thoroughly explored. This study aims to use low-cost sensors to develop devices that accurately measure solar ultraviolet radiation. The de vices should be low-cost, small, portable, and have low power consumption and IoT connectivity. For this purpose, three popular low-cost commercial sensors ML8511, UVM30A and VEML6075 are selected and implemented in several prototypes. The sensors are analyzed in terms of their spectral response, leveling, angular response and comparison with reference data. For that aim, experimental measurements are performed at the radiometric station of the Physics Department of the University of Extremadura in Badajoz, Spain. Results indicate that sensors of the same model might have different calibrations. The leveling and the angular response measurements indicate a strong azimuth dependence for the ML8511 and, especially, VEML6075 sensors, while the UVM30A sensor shows a much weaker dependence, probably due to the use of a circular diffuser. The angular response is identified as the main issue of the sensors, notably limiting their accuracy and preventing a widespread use. With the knowledge gained, a final version with LoRa communication and optimized power consumption is developed. The strength of the LoRa connection is measured at different locations on the University Campus using Receiver Signal Strength Indication. It ranges from -27 dB near the gateway to -122 dB at the farthest location on the Campus. The optimization of the power consumption allows 14 days of autonomy if operating only during daylight hours. The study illustrates the suitability of low-cost sensors for UV applications, provided that a good angular response of the sensors is ensured. It contributes to a wider use of these sensors for the measurement of air quality variables by identifying those characteristics that need to be improved by manufacturers to meet the standards.

UV Index for Public Health Awareness Based on OMI/NASA Satellite Data at King Abdulaziz University, Saudi Arabia

Exposure to ultraviolet radiation (UV) is essential for good health and formation of vitamin D while overexposure poses a risk to public health. Therefore, it is important to provide information to the public about the level of solar UV radiation. The ultraviolet index (UVI) is used to help avoid the negative effects of ultraviolet (UV) radiation on humans and to optimize individual exposure. There is limited ground measurement of solar UV radiation, but satellite Ozone Monitoring Instrument (OMIs) satellite products with a spatial resolution of 1 ° × 1 ° can be used to create UV index climatology at local noon time. In this study, we utilize OMI satellite products collected over the campus of King Abdulaziz University (KAU) (21.5° North and 39.1° East), Jeddah, Saudi Arabia, to estimate changes in exposure to UV over a period of 15 years (2004-2020). The results indicate a significantly increasing trend in UV index over this period. Between 2004 and 2020, daily “extreme” UV ( UVI > 11 , as defined by the World Health Organization (WHO)) occurred on 46.60% of days. The frequency of low UVI ( UVI < 2 ) was only about 0.06%. These results imply dangerous exposure levels to solar UV radiation on the KAU campus and call for safety measures to increase awareness and decrease direct exposure; for example, by implementing the United States Environmental Protection Agency (EPA) general guidelines.

Record-Breaking Increases in Arctic Solar Ultraviolet Radiation Caused by Exceptionally Large Ozone Depletion in 2020.

Measurements of solar ultraviolet radiation (UVR) performed between January and June 2020 at 10 Arctic and subarctic locations are compared with historical observations. Differences between 2020 and prior years are also assessed with total ozone column and UVR data from satellites. Erythemal (sunburning) UVR is quantified with the UV Index (UVI) derived from these measurements. UVI data show unprecedently large anomalies, occurring mostly between early March and mid‐April 2020. For several days, UVIs observed in 2020 exceeded measurements of previous years by up to 140%. Historical means were surpassed by more than six standard deviations at several locations in the Arctic. In northern Canada, the average UVI for March was about 75% larger than usual. UVIs in April 2020 were elevated on average by about 25% at all sites. However, absolute anomalies remained below 3.0 UVI units because the enhancements occurred during times when the solar elevation was still low.

PHOTOTOXICITY OF α-TERTHIENYL AND PSORALENE INROSE AND MUSTARD APHIDS (MACROSIPHUM ROSAE & LIPAPHIS ERYSIMI) IN DOON VALLEY

Climate change has an impact on agriculture and insect pests that affect the crop production. Aphid pests occur throughout the temperate region of the world andcause direct damage by sucking plants sap which affects growth and yield of the crops. Species of aphids are diverse and ubiquitous but their importance among crop differs.Ultraviolet radiation (UVR) is an electromagnetic radiation and constitutes about 10% of the total light output of sunlight. Ultraviolet-B coming due to ozone depletion is the most photo chemically reactive wavelength of solar radiation and important stressor to organisms particularly in their early stages of life and affect ecosystem. Psoralene and alpha- terthienyl are naturally occurring plant metabolites found in many crops and become photo reactive in presence of solar ultraviolet- B radiation. Measurement of solar ultraviolet radiation (UV-B and UV-E) was performed in Garhwalregion of Uttarakhand. Morphological, behavioural changes, mortality rate and glutathione contents were observed in mustard and roseaphids after ultraviolet-B irradiation with psoralene and α-terthienyl photo sensitizers. UV-B and UV-E radiation showed seasonal, diurnal and altitudinal variations. α- terthienyland psoralenewith ultraviolet-B radiation showed stunted growth, morphological changes, low reproduction and high mortality up to 26% in aphids. Reduction in glutathione (GSH) level in aphids was also observed after UV- B and photosensitizersexposure.Enhanced UV-B was found more toxic with photosensitizers andthus, can be used as natural insecticide. Dose, intensity and species dependent changes in toxicity of psoralene and α- terthienyl were observed in aphids. Resultsindicate that UV-B radiation with photosensitizers has toxic effect on aphids population, dispersal and diversity. Psoralene was found more toxic than α- terthienyl in aphids. Mustard aphid (Lipaphis erysimi) was found more sensitive than rose aphid (Macrosiphum rosae).

Inter-Comparison Campaign of Solar UVR Instruments under Clear Sky Conditions at Reunion Island (21°S, 55°E).

Measurement of solar ultraviolet radiation (UVR) is important for the assessment of potential beneficial and adverse impacts on the biosphere, plants, animals, and humans. Excess solar UVR exposure in humans is associated with skin carcinogenesis and immunosuppression. Several factors influence solar UVR at the Earth’s surface, such as latitude and cloud cover. Given the potential risks from solar UVR there is a need to measure solar UVR at different locations using effective instrumentation. Various instruments are available to measure solar UVR, but some are expensive and others are not portable, both restrictive variables for exposure assessments. Here, we compared solar UVR sensors commercialized at low or moderate cost to assess their performance and quality of measurements against a high-grade Bentham spectrometer. The inter-comparison campaign took place between March 2018 and February 2019 at Saint-Denis, La Réunion. Instruments evaluated included a Kipp&Zonen UVS-E-T radiometer, a Solar Light UV-Biometer, a SGLux UV-Cosine radiometer, and a Davis radiometer. Cloud fraction was considered using a SkyCamVision all-sky camera and the Tropospheric Ultraviolet Visible radiative transfer model was used to model clear-sky conditions. Overall, there was good reliability between the instruments over time, except for the Davis radiometer, which showed dependence on solar zenith angle. The Solar Light UV-Biometer and the Kipp&Zonen radiometer gave satisfactory results, while the low-cost SGLux radiometer performed better in clear sky conditions. Future studies should investigate temporal drift and stability over time.

The Shadow Rule, the UV Index, and the 5S Steps in the Tropics.

Solar ultraviolet radiation (UVR) induces the production of vitamin D (VD), but it also causes erythema and skin cancer among other diseases. The amount of UVR to get benefit and avoid harm is unknown. Some principles were proposed to provide accessible information on how to avoid overexposure to the Sun. They are (1) the Shadow Rule (SR); (2) the UV Index (UVI); and (3) the Slip, Slop, Slap, Seek, Slide (5S) steps. This work discusses these principles in the tropics, considering measurements of solar UVR, total ozone column, and cloudiness. Indeed, the SR leads to overexposures. The UVI is adequate for cloudless skies, but it does not consider radiation enhancement events by clouds. "Seek shade" in the 5S steps should be more emphasized as it is both the most efficient step in terms of avoiding direct sun and the friendliest step toward the environment. Therefore, photoprotection attitudes in the tropics should focus on the UVI and the 5S steps in addition to considering both VD sufficiency and environmental outcomes. The SR is clearly inaccurate.

The measurement of solar ultraviolet radiation in Kermanshah city over a one-year period from 2015 to 2016

The measurement of solar ultraviolet radiation in Kermanshah city over a one-year period from 2015 to 2016

Total column ozone and solar UV-B erythemal irradiance over Kishinev, Moldova

Results of the total column ozone and ultraviolet (UV-B) erythemally weighted irradiance measurements at the ground-based solar monitoring station at the Kishinev (Moldova) are presented. Diffuse and global components of solar UV-B erythemal irradiance on horizontal plane were continuously measured with sensors UV-S-B-C (of broadband 280-315 nm), Kipp&Zonen. Monthly totals of global and diffuse components of solar UV-B erythemal radiation reveal distinct seasonal variation with respective minimum in winter and maximum in summer. Typical values for these components in limiting cases are presented. A simple polynomial relationship between the global and diffuse components of solar UV-B erythemal radiation measured for cloudless days was derived. It was shown that coefficients of the polynomial depend on daily mean value of aerosol optical thickness (AOT). Collocated measurements of AOT have been carried out with the sunphotometer Cimel CE-318 within the framework of the Aerosol Robotic Network (AERONET) program, managed by NASA/GSFC. Total column ozone content was retrieved from direct solar ultraviolet radiation measurements at 3 discrete wavelengths centered at 305.5, 312.5, and 320 nm within the UV-B range. Ozone measurements were regularly carried out with the hand-held MICROTOPS II Ozonemeter, Solar Light Co. Monthly average values of total column ozone content measured with the MICROTOPS II at the Kishinev are in close agreement with those ones retrieved from the multiyear (1978-2004) database statistics acquired from satellite platforms measurements with the Total Ozone Mapping Spectrometer (TOMS). It was shown the existence of seasonal variability of the total column ozone content with respective minimum values observed at the end of autumn and winter, and maximum values observed at the end of winter and in spring. The maximum and minimum of daily mean values of total column ozone ever measured with TOMS at the satellite platforms overpassed Kishinev site, amounted of ~540 DU (on February 19, 1985) and ~204 DU (on December 1, 1999). Yearly mean value of total column ozone measured at the Kishinev was ~ 338 DU. Total column ozone measurements carried out with MICROTOPS at the Kishinev site from September 2003 to August 2004, gave maximum and minimum values of ozone daily means at ~ 489 DU (on February 12, 2004) and ~259 DU (on December 3, 2003). The estimation of total column ozone trend derived from the TOMS multi-year statistics was ~ -10 DU/decade.

Measurement of solar UV radiation in Antarctica with collagen sheets

Collagen sheets were used in a unique evaluation method to examine skin damage caused by ultraviolet (UV) light of short wavelength during a season of the Antarctic ozone hole. The collagen sheets were exposed outdoors for 25 and 50 d, in the spring when the ozone hole was formed and in the ozone-hole-free autumn. Extracts from the exposed collagen sheets were analyzed for total protein and terminal amino acid concentrations as an index of collagen fragmentation. The results show that the amount of extractable collagen and terminal amino acid concentration in the spring exposure were approximately double and five times higher, respectively, when compared with those in the autumn exposure. During the ozone hole occurrence, the terminal amino acid concentration of the extracted collagen was about five times higher when exposure lasted 50 d from mid-September to the end of October compared to when exposure lasted 25 d from mid-September to early October. This result could be attributed to a limited amount of short-wavelength UV radiation reaching the ground surface as a result of the low height of the sun in September, when the ozone hole occurred. In fact, UV radiation measurements taken at Syowa Station indicate that short-wavelength UV radiation in the range 290-295 nm was not detected until approximately 1-2 months after the beginning of the ozone hole occurrence.

Solar Ultraviolet Radiation Measurements in One of the Most Populous Cities of the World: Aspects Related to Skin Cancer Cases and Vitamin D Availability

A number of studies published in the scientific literature have shown the relationship between sun exposure and nonmelanoma skin cancer (NMSC) and vitamin D synthesis. However, the paucity of medical data, particularly in developing countries, hampers a global assessment of the impact of sun exposure on NMSC and vitamin D. To improve knowledge on this subject, this paper presents UV index (UVI) measurements performed in São Paulo City (SPC) in the period 2005-2008. It was found that 65% of the UVI measured 2 h around local noon during the summer show very high (8 < UVI < 10) and extreme (UVI > 11) levels according to the World Health Organization (WHO) classification. During the winter, 40% of the measurements around noontime show high or very high levels. In spite of worrisome recent statistics from SPC, showing that NMSCs make up about 28% of over a million of new cases of cancer in 2008, sun protection is not considered a real problem in these urban areas. UV measurements also show that every month of the year UV levels are high enough to ensure vitamin D production in human skin from incidental sun exposure.

Estimation of different biologically effective irradiances at Visakhapatnam (17.7°N, 83.3°E) from standard action spectra

Measurements of solar ultraviolet radiation in the biological band (280 - 320 nm) using a ground based UV-B Photometer at VISAKHAPATNAM have been used to estimate the biological effects of the incoming radiation on various species like human, animals, plants etc. with the help of standard action spectra. A comparison is made with TOMS ozone data to find the dependence on column ozone at a subtropical Indian station Visakhapatnam (17.7°N, 83.3°E). It is found that there is no significant change in the incoming biological effective radiation in the latitude (10 - 20° North) which corresponds to very less change in the columnar ozone content for this latitude. A bilinear regression model developed for this station was used to find the RAF (Radiation Amplification Factor) which indicates the change in the biological effect with respect to the corresponding change in ozone. The values of RAF for different biological effects were evaluated and are presented in this paper. Key words: UV-B irradiance, TOMS ozone, RAF, regression model, solar zenith angle, action spectrum.

Simplified Calibration for Broadband Solar Ultraviolet Radiation Measurements¶

Aspects of different calibration procedures for erythemally weighing broadband radiometers are presented in this study. These instruments are common in projects dealing with ultraviolet radiation effects on humans. Many erythemally weighing broadband radiometers are still operated using a single calibration factor (cf) that is provided with the instrument. The individual characteristics of every instrument are strongly dependent on the total ozone amount and the solar elevation. Therefore, a calibration procedure also has to take into account the ozone concentrations and the solar elevation to compensate for the effects of the individual characteristics and to provide comparable measurements. Given the variation of the ozone concentrations and the solar elevation, an individual cf has to be calculated for every measurement. Using a simplified version of the calibration procedure, which is presented in this study, can lessen this effort. Taking into account the relevant meteorological conditions for a measuring site, a single cf is calculated to compensate the individual characteristics of the instruments and therefore deliver comparable measurements with less effort.

Parameterization of daily solar global ultraviolet irradiation.

Daily values of solar global ultraviolet (UV) B and UVA irradiation as well as erythemal irradiation have been parameterized to be estimated from pyranometer measurements of daily global and diffuse irradiation as well as from atmospheric column ozone. Data recorded at the Meteorological Observatory Potsdam (52 degrees N, 107 m asl) in Germany over the time period 1997-2000 have been used to derive sets of regression coefficients. The validation of the method against independent data sets of measured UV irradiation shows that the parameterization provides a gain of information for UVB, UVA and erythemal irradiation referring to their averages. A comparison between parameterized daily UV irradiation and independent values of UV irradiation measured at a mountain station in southern Germany (Meteorological Observatory Hohenpeissenberg at 48 degrees N, 977 m asl) indicates that the parameterization also holds even under completely different climatic conditions. On a long-term average (1953-2000), parameterized annual UV irradiation values are 15% and 21% higher for UVA and UVB, respectively, at Hohenpeissenberg than they are at Potsdam. Daily global and diffuse irradiation measured at 28 weather stations of the Deutscher Wetterdienst German Radiation Network and grid values of column ozone from the EPTOMS satellite experiment served as inputs to calculate the estimates of the spatial distribution of daily and annual values of UV irradiation across Germany. Using daily values of global and diffuse irradiation recorded at Potsdam since 1937 as well as atmospheric column ozone measured since 1964 at the same site, estimates of daily and annual UV irradiation have been derived for this site over the period from 1937 through 2000, which include the effects of changes in cloudiness, in aerosols and, at least for the period of ozone measurements from 1964 to 2000, in atmospheric ozone. It is shown that the extremely low ozone values observed mainly after the eruption of Mt. Pinatubo in 1991 have substantially enhanced UVB irradiation in the first half of the 1990s. According to the measurements and calculations, the nonlinear long-term changes observed between 1968 and 2000 amount to +4%, ..., +5% for annual global irradiation and UVA irradiation mainly because of changing cloudiness and + 14%, ..., +15% for UVB and erythemal irradiation because of both changing cloudiness and decreasing column ozone. At the mountain site, Hohenpeissenberg, measured global irradiation and parameterized UVA irradiation decreased during the same time period by -3%, ..., -4%, probably because of the enhanced occurrence and increasing optical thickness of clouds, whereas UVB and erythemal irradiation derived by the parameterization have increased by +3%, ..., +4% because of the combined effect of clouds and decreasing ozone. The parameterizations described here should be applicable to other regions with similar atmospheric and geographic conditions, whereas for regions with significantly different climatic conditions, such as high mountainous areas and arctic or tropical regions, the representativeness of the regression coefficients would have to be approved. It is emphasized here that parameterizations, as the one described in this article, cannot replace measurements of solar UV radiation, but they can use existing measurements of solar global and diffuse radiation as well as data on atmospheric ozone to provide estimates of UV irradiation in regions and over time periods for which UV measurements are not available.

Characterisation of spectrophotometers used for spectral solar ultraviolet radiation measurements.

Spectrophotometers used for spectral measurements of the solar ultraviolet radiation need to be well characterised to provide accurate and reliable data. Since the characterisation and calibration are usually performed in the laboratory under conditions very different from those encountered during solar measurements, it is essential to address all issues concerned with the representativity of the laboratory characterisation with respect to the solar measurements. These include among others the instrument stability, the instrument linearity, the instrument responsivity, the wavelength accuracy, the spectral resolution, stray light rejection and the instrument dependence on ambient temperature fluctuations. These instrument parameters need to be determined often enough so that the instrument changes only marginally in the period between successive characterisations and therefore provides reliable data for the intervening period.

The measurement of solar ultraviolet radiation

High skin cancer rates, stratospheric ozone depletion and increased public interest and concern have resulted in a strong demand for solar ultraviolet radiation measurements and information. The Australian Radiation Laboratory (ARL) has been involved since the mid-1980s in the measurement of solar ultraviolet radiation (UVR) using spectroradiometers (SRM) and a network of broadband detectors at 18 sites in Australia and Antarctica and in Singapore through a collaborative agreement with the Singapore Institute of Science and Forensic Medicine. Measurement locations range from equatorial (Singapore, 1.3°N) through tropical (Darwin, 12.4°S) to polar (Mawson, 67.6°S) and as a result there are many difficulties associated with maintenance and calibration of the network detectors, and transfer of data to ensure an accurate and reliable data collection. Calibration procedures for the various detectors involve the comparison with simultaneous spectral measurements using a portable SRM incorporating a double monochromator, calibrated against traceable standard lamps. Laboratory measurements of cosine response and responsivity are also made. Detectors are intercompared at the Yallambie site for a number of months before installation at another location. As an additional check on the calibrations, computer models of solar UVR at the earth's surface for days with clear sky and known ozone are compared with the UV radiometer measurements.

Ground‐based measurements of solar ultraviolet radiation in Tibet: Preliminary results

Measurements were carried out on Tibetan Plateau (Lhasa, 3648 m above sea level) with a multi‐channel moderate bandwidth filter instrument during the period from June 24. to November 30., 1996. The analysis of preliminary data shows that hourly mean CIE‐weighted biologically effective UV dose rate at local noon can reach to as high as 390.5 mW/m² . The corresponding average value was 225.4 mW/m²; Due to the combined effect of cloud cover variation with ozone variation, the increasing trend of this UV dose rate exists during this period of measurements. The relation between the ratio of irradiance close to noon at 340nm to that at 305nm and total ozone column shows that the variation of total ozone column may also cause the variation of UV radiation. In addition, the UV dose rate in the morning is slightly higher than that at afternoon with same solar zenith angle.

足利市における太陽紫外放射と日常生活で受ける紫外放射の測定

足利市における太陽紫外放射と日常生活で受ける紫外放射の測定

SIMULATION OF BROAD-BAND AND SPECTRAL SOLAR ULTRAVIOLET RADIATION

Daily broad-band and spectral measurements of solar ultraviolet radiation reaching the ground at Athens, Greece (38°N, 24°E) during 1989-1993 in conjunction with daily total ozone measurements deduced from satellite and ground-based instrumentation were used to investigate their association. Furthermore, employing a new parametric model, the spectral and broad-band solar ultraviolet radiation for die period 1979-1993 were calculated considering the total ozone values, derived from both the satellite Nimbus-7, and the ground-based Dobson spectrophotometer.

Solar ultraviolet radiation and total ozone, as derived from satellite and ground‐based instrumentation

Daily broad‐band measurements of solar ultraviolet radiation reaching the ground at Athens, Greece (38°N, 24°E) during 1989–1991 in conjunction with daily total ozone measurements deduced from satellite and ground‐based instrumentation were used to investigate their association. Furthermore, employing a parametric model, the spectral and broad‐band solar ultraviolet radiation for the period 1979–1991 were calculated considering the total ozone values, derived from the satellite Nimbus‐7.Total ozone reductions of 2.5% during summertime and 7% during wintertime per decade, cause an increase in erythemally active UV‐B irradiance of 5% and 14% respectively.