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Ultraviolet index

January 09, 2023

The ultraviolet index, or UV index, is an international standard measurement of the strength of the sunburn-producing ultraviolet (UV) radiation at a particular place and time. It is primarily used in daily and hourly forecasts aimed at the general public.

The UV index is designed as an open-ended linear scale, directly proportional to the intensity of UV radiation that causes human skin to sunburn.[1] Using the Fitzpatrick scale, a light-skinned individual would experience sunburn in about 30 minutes at UV index 6, without sunscreen.[citation needed] That same individual would experience sunburn in only 15 minutes if the UV index was at 12.

The purpose of the UV index is to help people effectively protect themselves from UV radiation, which has health benefits in moderation but in excess causes sunburn, skin aging, DNA damage, skin cancer, immunosuppression,[2] and eye damage, such as cataracts. The scale was developed by Canadian scientists in 1992, and then adopted and standardized by the UN's World Health Organization and World Meteorological Organization in 1994.[3] Public health organizations recommend that people protect themselves (for example, by applying sunscreen to the skin and wearing a hat and sunglasses) if they spend substantial time outdoors when the UV index is 3 or higher; see the table below for more detailed recommendations.

Description

The UV index is a linear scale; each increase in value corresponds to a constant decrease in time to sunburn. Higher values represent a greater risk of sunburn (which is correlated with other health risks) due to UV exposure. An index of 0 corresponds to zero UV radiation, as is essentially the case at night. An index of 10 corresponds roughly to midday summer sunlight with a clear sky when the UV index was originally designed; now summertime index values in the tens are common for tropical latitudes, mountainous altitudes, areas with ice/water reflectivity and areas with above-average ozone layer depletion.[4]

While the UV index can be calculated from a direct measurement of the UV spectral power at a given location, as some inexpensive portable devices are able to approximate, the value given in weather reports is usually a prediction based on a computer model. Although this may be in error (especially when cloud conditions are unexpectedly heavy or light), it is usually within ±1 UV index unit as that which would be measured.[5]

 
Typical variation of UV index by time of day and time of year, around 40.71 -74.01, based on FastRT UV Calculator[6]

When the UV index is presented on a daily basis, it represents UV intensity around the sun's highest point in the day, called solar noon, halfway between sunrise and sunset. This typically occurs between 11:30 and 12:30, or between 12:30 and 13:30 in areas where daylight saving time is being observed. Predictions are made by a computer model that accounts for the effects of sun-earth distance, solar zenith angle, total ozone amount, tropospheric aerosol optical depth, elevation, snow/ice reflectivity and cloud transmission, all of which influence the amount of UV radiation at the surface.[4] The calculations are weighted in favor of the UV wavelengths to which human skin is most sensitive, according to the CIE-standard McKinlay–Diffey erythemal action spectrum.[7][8] The resulting UV index cannot be expressed in pure physical units, but is a good indicator of likely sunburn damage.

Unlike other common environmental scales such as decibels or the Richter scale, which are logarithmic (the severity multiplies for each step on the scale, growing exponentially), the UV index is linear and increase at a constant rate. This means that an index of 10 is twice as strong as an index of 5.

Technical definition

 
Sunburn effect (as measured by the UV index) is the product of the sunlight power spectrum (radiation intensity) and the erythemal action spectrum (skin sensitivity) across the range of UV wavelengths.[7][8]

The UV index is a number linearly related to the intensity of sunburn-producing UV radiation at a given point on the Earth's surface. It cannot be simply related to the irradiance (measured in W/m2) because the UV of greatest concern occupies a spectrum of wavelengths from 295 to 325 nm, and shorter wavelengths have already been absorbed a great deal when they arrive at the earth's surface. However, skin damage from sunburn is related to wavelength, the shorter wavelengths being much more damaging. The UV power spectrum (expressed as watts per square meter per nanometer of wavelength) is therefore multiplied by a weighting curve known as the erythemal action spectrum, and the result is integrated over the whole spectrum. This gives a weighted figure (sometimes called Diffey-weighted UV irradiance, or DUV, or erythemal dose rate) typically around 250 mW/m2 in the midday summer sunlight. For convenience, this is divided by 25 mW/m2 to produce an index[9][10] nominally from 0 to 11+, though ozone depletion is now resulting in higher values.

To illustrate the spectrum weighting principle, the incident power density in midday summer sunlight is typically 0.6 mW/(nm m2) at 295 nm, 74 mW/(nm m2) at 305 nm, and 478 mW/(nm m2) at 325 nm. (Note the huge absorption that has already taken place in the atmosphere at short wavelengths.) The erythemal weighting factors applied to these figures are 1.0, 0.22, and 0.003 respectively. (Also note the huge increase in sunburn damage caused by the shorter wavelengths; e.g., for the same irradiance, 305 nm is 22% as damaging as 295 nm, and 325 nm is 0.3% as damaging as 295 nm.) Integration of these values using all the intermediate weightings over the full spectral range of 290 nm to 400 nm[9] produces a figure of 264 mW/m2 (the DUV), which is then divided by 25 mW/m2 to give a UV index of 10.6.[10]

History

After sporadic attempts by various meteorologists to define a "sunburn index" and growing concern about ozone depletion, Environment Canada scientists James B. Kerr, C. Thomas McElroy, and David I. Wardle invented the modern UV index in Toronto, Ontario. Environment Canada launched it as part of the weather forecast on May 27, 1992, making Canada the first country in the world to issue official predictions of UV levels for the next day.[11][12] Many other countries followed suit with their own UV indices. Initially, the methods of calculating and reporting a UV index varied significantly from country to country. A global UV index, first standardized by the World Health Organization and World Meteorological Organization in 1994,[13] gradually replaced the inconsistent regional versions, specifying not only a uniform calculation method (the Canadian definition) but also standard colors and graphics for visual media.[14] In the United States, the WHO standards officially replaced the original US standards in 2004.[15]

On December 29, 2003, a world-record ground-level UV index of 43.3 was detected at Bolivia's Licancabur volcano,[16][17] though other scientists dispute readings higher than 26.[18]

In 2005, the United States[19] and Australia[20] launched the UV Alert. While the two countries have different baseline UV intensity requirements before issuing an alert, their common goal is to raise awareness of the dangers of over-exposure to the Sun on days with intense UV radiation.

In 2007, the United Nations honored UV index inventors Kerr, McElroy, and Wardle with the Innovators Award for their far-reaching work on reducing public health risks from UV radiation.[21] In the same year, a survey among meteorologists ranked the development of the UV index as #11 on The Weather Channel's 100 Biggest Weather Moments.

In 2022, a new mobile phone application that provides localized information on ultraviolet (UV) radiation levels has been launched by the World Health Organization (WHO), the World Meteorological Organization (WMO), the United Nations Environment Programme (UNEP) and the International Labour Organization (ILO).[22]

Index usage

The recommendations below are for average adults with lightly tanned skin[citation needed] (Fitzpatrick scale: Type II). Those with darker skin (Fitzpatrick scale: Type IV+) are more likely to withstand greater sun exposure, while extra precautions are needed for children, seniors, particularly fair-skinned adults, and those who have greater sun sensitivity for medical reasons[23] or from UV exposure in previous days.

When the day's predicted UV index is within various numerical ranges, the recommendations for protection are as follows:[14][24]

UV index Media graphic color Risk of harm from unprotected sun exposure, for the average adult Recommended protection
0 - 2 Green "Low" A UV index reading of 0 to 2 means low danger from the Sun's UV rays for the average person.

Wear sunglasses on bright days. If you burn easily, cover up and use broad spectrum SPF 15+ sunscreen. Bright surfaces,[23] sand, water, and snow,[14] will increase UV exposure.

3 - 5 Yellow "Moderate" A UV index reading of 3 to 5 means moderate risk of harm from unprotected sun exposure.

Stay in shade near midday when the Sun is strongest. If outdoors, wear sun-protective clothing, a wide-brimmed hat, and UV-blocking sunglasses. Generously apply broad spectrum SPF 15+ sunscreen every 1.5 hours, even on cloudy days, and after swimming or sweating. Bright surfaces, such as sand, water, and snow, will increase UV exposure.

6 - 7 Orange "High" A UV index reading of 6 to 7 means high risk of harm from unprotected sun exposure. Protection against skin and eye damage is needed.

Reduce time in the sun between 10 a.m. and 4 p.m. If outdoors, seek shade and wear sun-protective clothing, a wide-brimmed hat, and UV-blocking sunglasses. Generously apply broad spectrum SPF 15+ sunscreen every 1.5 hours, even on cloudy days, and after swimming or sweating. Bright surfaces, such as sand, water, and snow, will increase UV exposure.

8 - 10 Red "Very high" A UV index reading of 8 to 10 means very high risk of harm from unprotected sun exposure. Take extra precautions because unprotected skin and eyes will be damaged and can burn quickly.

Minimize sun exposure between 10 a.m. and 4 p.m. If outdoors, seek shade and wear sun-protective clothing, a wide-brimmed hat, and UV-blocking sunglasses. Generously apply broad spectrum SPF 15+ sunscreen every 1.5 hours, even on cloudy days, and after swimming or sweating. Bright surfaces, such as sand, water, and snow, will increase UV exposure.

11+ Violet "Extreme" A UV index reading of 11 or more means extreme risk of harm from unprotected sun exposure. Take all precautions because unprotected skin and eyes can burn in minutes.

Try to avoid sun exposure between 10 a.m. and 4 p.m. If outdoors, seek shade and wear sun-protective clothing, a wide-brimmed hat, and UV-blocking sunglasses. Generously apply broad spectrum SPF 15+ sunscreen every 1.5 hours, even on cloudy days, and after swimming or sweating. Bright surfaces, such as sand, water, and snow, will increase UV exposure.

See also

References

  1. ^ "UV Index Overview". U.S. Environmental Protection Agency. 2022.
  2. ^ Hanneman, K. K.; et al. (January 2006). "Ultraviolet immunosuppression: Mechanisms and consequences". Dermatologic Clinics. 24 (1): 19–25. doi:10.1016/j.det.2005.08.003. PMID 16311164.
  3. ^ Heckman, C. J.; Liang, K.; Riley, M. (2022). "Awareness, Understanding, Use, and Impact of the UV Index: A Systematic Review of Over Two Decades of International Research". Preventive Medicine. 123: 71–83. doi:10.1016/j.ypmed.2019.03.004. PMC 6534479. PMID 30844501.
  4. ^ a b Fioletov, V.; et al. (July–August 2010). "The UV index: Definition, distribution and factors affecting it". Canadian Journal of Public Health. 101 (4): I5–I9. doi:10.1007/BF03405303. PMC 6974160. PMID 21033538.
  5. ^ "UV Index: Is it Validated?". NOAA/National Weather Service. 2006.
  6. ^ Engelsen, Ola & Kylling, Arve (April 2005). "Fast simulation tool for ultraviolet radiation at the earth's surface". Optical Engineering. 44 (4). 041012. Bibcode:2005OptEn..44d1012E. doi:10.1117/1.1885472.
  7. ^ a b McKinlay, A. F. & Diffey, B. L. (1987). "A reference action spectrum for ultraviolet induced erythema in human skin". CIE Journal. 6 (1): 17–22.
  8. ^ a b "UV Spectral Irradiances & Erythemal Action Spectrum". NOAA. 2006.
  9. ^ a b . SunWise. U.S. Environmental Protection Agency. 2015-08-21. Archived from the original on November 29, 2012.
  10. ^ a b . Smithsonian Institution. Archived from the original on June 13, 2010. (This source contains some numerical errors.)
  11. ^ Kerr, J. B.; et al. (1994). "The Canadian Ozone Watch and UV-B advisory programs". Ozone in the Troposphere and Stratosphere, Part 2: Proceedings of the Quadrennial Ozone Symposium 1992. NASA/Goddard Space Flight Center: 794–797. N95-11093.
  12. ^ (Press release). Environment Canada. May 27, 2002. Archived from the original on July 14, 2014.
  13. ^ Report of the WMO Meeting of Experts on UV-B Measurements, Data Quality and Standardization of UV Indices, 1994. Global Atmosphere Watch (Report). World Meteorological Organization. 1995. WMO/TD-No. 625.
  14. ^ a b c Organization, World Meteorological (2002). "Global Solar UV Index: A Practical Guide". World Health Organization. hdl:10665/42459.
  15. ^ "A Guide to the UV Index" (PDF). U.S. Environmental Protection Agency. 2022.
  16. ^ Oskin, Becky (July 8, 2014). "Blazing World Record: Strongest UV Rays Measured in South America". LiveScience.com.
  17. ^ Cabrol, Nathalie A.; et al. (July 8, 2014). "Record solar UV irradiance in the tropical Andes". Frontiers in Environmental Science. 2 (19). 19. Bibcode:2014FrES....2...19C. doi:10.3389/fenvs.2014.00019.
  18. ^ McKenzie, Richard L.; et al. (April 8, 2015). "Comment on "Record solar UV irradiance in the tropical Andes, by Cabrol et al."". Frontiers in Environmental Science. 3. 26. doi:10.3389/fenvs.2015.00026.
  19. ^ . SunWise. U.S. Environmental Protection Agency. 2015-08-21. Archived from the original on October 14, 2011.
  20. ^ . SunSmart. Cancer Council Victoria. Archived from the original on January 26, 2016.
  21. ^ . World Meteorological Organization. October 2007. Archived from the original on July 14, 2014.
  22. ^ "SunSmart Global UV App helps protect you from the dangers of the sun and promotes public health". World Health Organization. 2022.
  23. ^ a b Dresbach, Sereana Howard & Brown, Wanda (2008). (PDF). The Invisible Environment Fact Sheet Series. The Ohio State University. CDFS-199-08. Archived from the original (PDF) on January 17, 2009.
  24. ^ "UV Index Scale". Sun Safety. U.S. Environmental Protection Agency. 2013-02-04. Retrieved June 28, 2019.

External links

  • Real-time Global Ultraviolet Index - A graphical view of the current UV index for the globe.
  • Radiation: The ultraviolet (UV) index - World Health Organization
  • Europe UV Index Forecast - European Climate and Health Observatory
  • Australian UV Index Forecast - Australian Bureau of Meteorology
  • United States UV index forecast - National Weather Service: Climate Prediction Center
  • UV Index Forecasts - UV Index Today: Hourly USA UV Index Forecasts

January 09, 2023
ultraviolet, index, ultraviolet, index, index, international, standard, measurement, strength, sunburn, producing, ultraviolet, radiation, particular, place, time, primarily, used, daily, hourly, forecasts, aimed, general, public, index, designed, open, ended,. The ultraviolet index or UV index is an international standard measurement of the strength of the sunburn producing ultraviolet UV radiation at a particular place and time It is primarily used in daily and hourly forecasts aimed at the general public The UV index is designed as an open ended linear scale directly proportional to the intensity of UV radiation that causes human skin to sunburn 1 Using the Fitzpatrick scale a light skinned individual would experience sunburn in about 30 minutes at UV index 6 without sunscreen citation needed That same individual would experience sunburn in only 15 minutes if the UV index was at 12 The purpose of the UV index is to help people effectively protect themselves from UV radiation which has health benefits in moderation but in excess causes sunburn skin aging DNA damage skin cancer immunosuppression 2 and eye damage such as cataracts The scale was developed by Canadian scientists in 1992 and then adopted and standardized by the UN s World Health Organization and World Meteorological Organization in 1994 3 Public health organizations recommend that people protect themselves for example by applying sunscreen to the skin and wearing a hat and sunglasses if they spend substantial time outdoors when the UV index is 3 or higher see the table below for more detailed recommendations Contents 1 Description 2 Technical definition 3 History 4 Index usage 5 See also 6 References 7 External linksDescription EditThe UV index is a linear scale each increase in value corresponds to a constant decrease in time to sunburn Higher values represent a greater risk of sunburn which is correlated with other health risks due to UV exposure An index of 0 corresponds to zero UV radiation as is essentially the case at night An index of 10 corresponds roughly to midday summer sunlight with a clear sky when the UV index was originally designed now summertime index values in the tens are common for tropical latitudes mountainous altitudes areas with ice water reflectivity and areas with above average ozone layer depletion 4 While the UV index can be calculated from a direct measurement of the UV spectral power at a given location as some inexpensive portable devices are able to approximate the value given in weather reports is usually a prediction based on a computer model Although this may be in error especially when cloud conditions are unexpectedly heavy or light it is usually within 1 UV index unit as that which would be measured 5 Typical variation of UV index by time of day and time of year around 40 71 74 01 based on FastRT UV Calculator 6 When the UV index is presented on a daily basis it represents UV intensity around the sun s highest point in the day called solar noon halfway between sunrise and sunset This typically occurs between 11 30 and 12 30 or between 12 30 and 13 30 in areas where daylight saving time is being observed Predictions are made by a computer model that accounts for the effects of sun earth distance solar zenith angle total ozone amount tropospheric aerosol optical depth elevation snow ice reflectivity and cloud transmission all of which influence the amount of UV radiation at the surface 4 The calculations are weighted in favor of the UV wavelengths to which human skin is most sensitive according to the CIE standard McKinlay Diffey erythemal action spectrum 7 8 The resulting UV index cannot be expressed in pure physical units but is a good indicator of likely sunburn damage Unlike other common environmental scales such as decibels or the Richter scale which are logarithmic the severity multiplies for each step on the scale growing exponentially the UV index is linear and increase at a constant rate This means that an index of 10 is twice as strong as an index of 5 Technical definition Edit Sunburn effect as measured by the UV index is the product of the sunlight power spectrum radiation intensity and the erythemal action spectrum skin sensitivity across the range of UV wavelengths 7 8 The UV index is a number linearly related to the intensity of sunburn producing UV radiation at a given point on the Earth s surface It cannot be simply related to the irradiance measured in W m2 because the UV of greatest concern occupies a spectrum of wavelengths from 295 to 325 nm and shorter wavelengths have already been absorbed a great deal when they arrive at the earth s surface However skin damage from sunburn is related to wavelength the shorter wavelengths being much more damaging The UV power spectrum expressed as watts per square meter per nanometer of wavelength is therefore multiplied by a weighting curve known as the erythemal action spectrum and the result is integrated over the whole spectrum This gives a weighted figure sometimes called Diffey weighted UV irradiance or DUV or erythemal dose rate typically around 250 mW m2 in the midday summer sunlight For convenience this is divided by 25 mW m2 to produce an index 9 10 nominally from 0 to 11 though ozone depletion is now resulting in higher values To illustrate the spectrum weighting principle the incident power density in midday summer sunlight is typically 0 6 mW nm m2 at 295 nm 74 mW nm m2 at 305 nm and 478 mW nm m2 at 325 nm Note the huge absorption that has already taken place in the atmosphere at short wavelengths The erythemal weighting factors applied to these figures are 1 0 0 22 and 0 003 respectively Also note the huge increase in sunburn damage caused by the shorter wavelengths e g for the same irradiance 305 nm is 22 as damaging as 295 nm and 325 nm is 0 3 as damaging as 295 nm Integration of these values using all the intermediate weightings over the full spectral range of 290 nm to 400 nm 9 produces a figure of 264 mW m2 the DUV which is then divided by 25 mW m2 to give a UV index of 10 6 10 History EditAfter sporadic attempts by various meteorologists to define a sunburn index and growing concern about ozone depletion Environment Canada scientists James B Kerr C Thomas McElroy and David I Wardle invented the modern UV index in Toronto Ontario Environment Canada launched it as part of the weather forecast on May 27 1992 making Canada the first country in the world to issue official predictions of UV levels for the next day 11 12 Many other countries followed suit with their own UV indices Initially the methods of calculating and reporting a UV index varied significantly from country to country A global UV index first standardized by the World Health Organization and World Meteorological Organization in 1994 13 gradually replaced the inconsistent regional versions specifying not only a uniform calculation method the Canadian definition but also standard colors and graphics for visual media 14 In the United States the WHO standards officially replaced the original US standards in 2004 15 On December 29 2003 a world record ground level UV index of 43 3 was detected at Bolivia s Licancabur volcano 16 17 though other scientists dispute readings higher than 26 18 In 2005 the United States 19 and Australia 20 launched the UV Alert While the two countries have different baseline UV intensity requirements before issuing an alert their common goal is to raise awareness of the dangers of over exposure to the Sun on days with intense UV radiation In 2007 the United Nations honored UV index inventors Kerr McElroy and Wardle with the Innovators Award for their far reaching work on reducing public health risks from UV radiation 21 In the same year a survey among meteorologists ranked the development of the UV index as 11 on The Weather Channel s 100 Biggest Weather Moments In 2022 a new mobile phone application that provides localized information on ultraviolet UV radiation levels has been launched by the World Health Organization WHO the World Meteorological Organization WMO the United Nations Environment Programme UNEP and the International Labour Organization ILO 22 Index usage EditThe recommendations below are for average adults with lightly tanned skin citation needed Fitzpatrick scale Type II Those with darker skin Fitzpatrick scale Type IV are more likely to withstand greater sun exposure while extra precautions are needed for children seniors particularly fair skinned adults and those who have greater sun sensitivity for medical reasons 23 or from UV exposure in previous days When the day s predicted UV index is within various numerical ranges the recommendations for protection are as follows 14 24 UV index Media graphic color Risk of harm from unprotected sun exposure for the average adult Recommended protection0 2 Green Low A UV index reading of 0 to 2 means low danger from the Sun s UV rays for the average person Wear sunglasses on bright days If you burn easily cover up and use broad spectrum SPF 15 sunscreen Bright surfaces 23 sand water and snow 14 will increase UV exposure 3 5 Yellow Moderate A UV index reading of 3 to 5 means moderate risk of harm from unprotected sun exposure Stay in shade near midday when the Sun is strongest If outdoors wear sun protective clothing a wide brimmed hat and UV blocking sunglasses Generously apply broad spectrum SPF 15 sunscreen every 1 5 hours even on cloudy days and after swimming or sweating Bright surfaces such as sand water and snow will increase UV exposure 6 7 Orange High A UV index reading of 6 to 7 means high risk of harm from unprotected sun exposure Protection against skin and eye damage is needed Reduce time in the sun between 10 a m and 4 p m If outdoors seek shade and wear sun protective clothing a wide brimmed hat and UV blocking sunglasses Generously apply broad spectrum SPF 15 sunscreen every 1 5 hours even on cloudy days and after swimming or sweating Bright surfaces such as sand water and snow will increase UV exposure 8 10 Red Very high A UV index reading of 8 to 10 means very high risk of harm from unprotected sun exposure Take extra precautions because unprotected skin and eyes will be damaged and can burn quickly Minimize sun exposure between 10 a m and 4 p m If outdoors seek shade and wear sun protective clothing a wide brimmed hat and UV blocking sunglasses Generously apply broad spectrum SPF 15 sunscreen every 1 5 hours even on cloudy days and after swimming or sweating Bright surfaces such as sand water and snow will increase UV exposure 11 Violet Extreme A UV index reading of 11 or more means extreme risk of harm from unprotected sun exposure Take all precautions because unprotected skin and eyes can burn in minutes Try to avoid sun exposure between 10 a m and 4 p m If outdoors seek shade and wear sun protective clothing a wide brimmed hat and UV blocking sunglasses Generously apply broad spectrum SPF 15 sunscreen every 1 5 hours even on cloudy days and after swimming or sweating Bright surfaces such as sand water and snow will increase UV exposure See also EditFitzpatrick scale Health effects of sunlight exposure Sun protective clothing SunscreenReferences Edit UV Index Overview U S Environmental Protection Agency 2022 Hanneman K K et al January 2006 Ultraviolet immunosuppression Mechanisms and consequences Dermatologic Clinics 24 1 19 25 doi 10 1016 j det 2005 08 003 PMID 16311164 Heckman C J Liang K Riley M 2022 Awareness Understanding Use and Impact of the UV Index A Systematic Review of Over Two Decades of International Research Preventive Medicine 123 71 83 doi 10 1016 j ypmed 2019 03 004 PMC 6534479 PMID 30844501 a b Fioletov V et al July August 2010 The UV index Definition distribution and factors affecting it Canadian Journal of Public Health 101 4 I5 I9 doi 10 1007 BF03405303 PMC 6974160 PMID 21033538 UV Index Is it Validated NOAA National Weather Service 2006 Engelsen Ola amp Kylling Arve April 2005 Fast simulation tool for ultraviolet radiation at the earth s surface Optical Engineering 44 4 041012 Bibcode 2005OptEn 44d1012E doi 10 1117 1 1885472 a b McKinlay A F amp Diffey B L 1987 A reference action spectrum for ultraviolet induced erythema in human skin CIE Journal 6 1 17 22 a b UV Spectral Irradiances amp Erythemal Action Spectrum NOAA 2006 a b How UV Index is Calculated SunWise U S Environmental Protection Agency 2015 08 21 Archived from the original on November 29 2012 a b How Is the UV Index Calculated Smithsonian Institution Archived from the original on June 13 2010 This source contains some numerical errors Kerr J B et al 1994 The Canadian Ozone Watch and UV B advisory programs Ozone in the Troposphere and Stratosphere Part 2 Proceedings of the Quadrennial Ozone Symposium 1992 NASA Goddard Space Flight Center 794 797 N95 11093 Environment Canada s UV Index Celebrates Ten Years Now Bringing Sun Safety Messages to 26 Countries Press release Environment Canada May 27 2002 Archived from the original on July 14 2014 Report of the WMO Meeting of Experts on UV B Measurements Data Quality and Standardization of UV Indices 1994 Global Atmosphere Watch Report World Meteorological Organization 1995 WMO TD No 625 a b c Organization World Meteorological 2002 Global Solar UV Index A Practical Guide World Health Organization hdl 10665 42459 A Guide to the UV Index PDF U S Environmental Protection Agency 2022 Oskin Becky July 8 2014 Blazing World Record Strongest UV Rays Measured in South America LiveScience com Cabrol Nathalie A et al July 8 2014 Record solar UV irradiance in the tropical Andes Frontiers in Environmental Science 2 19 19 Bibcode 2014FrES 2 19C doi 10 3389 fenvs 2014 00019 McKenzie Richard L et al April 8 2015 Comment on Record solar UV irradiance in the tropical Andes by Cabrol et al Frontiers in Environmental Science 3 26 doi 10 3389 fenvs 2015 00026 UV Alert SunWise U S Environmental Protection Agency 2015 08 21 Archived from the original on October 14 2011 What is UV SunSmart Cancer Council Victoria Archived from the original on January 26 2016 Ozone awards World Meteorological Organization October 2007 Archived from the original on July 14 2014 SunSmart Global UV App helps protect you from the dangers of the sun and promotes public health World Health Organization 2022 a b Dresbach Sereana Howard amp Brown Wanda 2008 Ultraviolet Radiation PDF The Invisible Environment Fact Sheet Series The Ohio State University CDFS 199 08 Archived from the original PDF on January 17 2009 UV Index Scale Sun Safety U S Environmental Protection Agency 2013 02 04 Retrieved June 28 2019 External links EditReal time Global Ultraviolet Index A graphical view of the current UV index for the globe Radiation The ultraviolet UV index World Health Organization Europe UV Index Forecast European Climate and Health Observatory Australian UV Index Forecast Australian Bureau of Meteorology United States UV index forecast National Weather Service Climate Prediction Center UV Index Forecasts UV Index Today Hourly USA UV Index Forecasts Retrieved from https en wikipedia org w index php title Ultraviolet index amp oldid 1121224425, wikipedia, wiki, book, books, library,

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