Validation of Satellite Estimated Solar Ultraviolet Radiation Data with Ground Based data in Kathmandu, Nepal

The main objective of this study is to validate the satellite estimated solar Ultraviolet radiation data with ground based data in Kathmandu (27.72 N, 85.32 E), located at an elevation of 1350m, from the sea level. The ground based measurement and the satellite estimation were performed by NILU-UV irradiance meter and EOS Aura OMI satellite respectively. The NILU-UV irradiance meter is a six channel 0 0 radiometer designed to measure hemispherical irradiances on a fat surface. Meanwhile the Ozone Monitoring Instrument (OMI) on board, the NASA EOS Aura space craft is a nadir viewing spectrometer that measures solar refected and back scattered light in ultraviolet and visible spectrum. The study is based on OMI and ground based (GB), Ultraviolet Radiation (UVR) data. Considering these data the relative differences between predicted OMI and ground based Ultraviolet Index (UVI) assuming normal distribution ±1σ was found to be 24.8±13.7% in July. Further study showed that the ratio of predicted OMI, UVI to that determined from ground based measurement is 1.14. Also the relative difference in UVI in corrected condition in summer season was found to be 5.8%. The correlation between predicted UVI and ground based UVI was found to be signifcant. Journal of the Institute of Engineering, 2015, 11(1): 101-107

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Solar UV Index at Different Altitudes of Nepal

Journal of the Institute of Engineering ◽

10.3126/jie.v14i1.20085 ◽

2018 ◽

Vol 14 (1) ◽

pp. 200-205

Author(s):

Niranjan Prasad Sharma

Keyword(s):

Flat Surface ◽

Scattered Light ◽

Visible Spectrum ◽

Ozone Monitoring Instrument ◽

Uv Index ◽

Uv Irradiance ◽

Solar Uv ◽

Ozone Monitoring ◽

Solar Ultraviolet ◽

Ultraviolet Index

The main objective of this research is to study the satellite estimated solar Ultraviolet data alongside the ground based data in Nepal. Kathmandu (27.72°N, 85.32°>E), Pokhara (28.22°N, 83.32°E) Biratnagar (26.45°N, 87.27°E) and Lukla (27.69°N, 86.73°E) are located at an elevation of 1350m, 800m, 72m and 2850m respectively from the sea level. The ground based measurements and the satellite estimation were performed by NILU-UV irradiance meter and EOS Aura OMI satellite respectively. The NILU-UV irradiance meter is a six channel radiometer designed to measure hemispherical irradiances on a flat surface. Meanwhile the Ozone Monitoring Instrument (OMI) on board, the NASA EOS Aura space craft is a nadir viewing spectrometer that measures solar reflected and back scattered light in ultraviolet and visible spectrum. The study was performed for 3 years Ultraviolet Radiation (UVR) data. This study showed that the ratio of predicted OMI Ultraviolet Index (UVI) to that determined from the ground based measurement was less than 1.21 except in Lukla.Journal of the Institute of Engineering, 2018, 14(1): 200-205

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Spatiotemporal analysis of solar ultraviolet radiation based on Ozone Monitoring Instrument dataset in Iran, 2005–2019

Environmental Pollution ◽

10.1016/j.envpol.2021.117643 ◽

2021 ◽

pp. 117643

Author(s):

Reza Gholamnia ◽

Mehrnoosh Abtahi ◽

Sina Dobaradaran ◽

Ali Koolivand ◽

Sahand Jorfi ◽

...

Keyword(s):

Ultraviolet Radiation ◽

Spatiotemporal Analysis ◽

Ozone Monitoring Instrument ◽

Solar Ultraviolet Radiation ◽

Monitoring Instrument ◽

Ozone Monitoring ◽

Solar Ultraviolet

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Comparison of OMI ozone and UV irradiance data with ground-based measurements at two French sites

Atmospheric Chemistry and Physics ◽

10.5194/acp-8-4517-2008 ◽

2008 ◽

Vol 8 (16) ◽

pp. 4517-4528 ◽

Cited By ~ 63

Author(s):

V. Buchard ◽

C. Brogniez ◽

F. Auriol ◽

B. Bonnel ◽

J. Lenoble ◽

...

Keyword(s):

Total Ozone ◽

Relative Difference ◽

Ozone Monitoring Instrument ◽

Dose Rates ◽

Clear Sky ◽

The North ◽

Uv Irradiance ◽

Relative Differences ◽

Sky Conditions ◽

Better Than

Abstract. Ozone Monitoring Instrument (OMI), launched in July 2004, is dedicated to the monitoring of the Earth's ozone, air quality and climate. OMI is the successor of the Total Ozone Mapping Spectrometer (TOMS) instruments and provides among other atmospheric and radiometric quantities the total column of ozone (TOC), the surface ultraviolet (UV) irradiance at several wavelengths, the erythemal dose rates and the erythemal daily doses. The main objective of this work is to compare OMI data with data from ground-based instruments in order to use OMI products (collection 2) for scientific studies. The Laboratoire d'Optique Atmosphérique (LOA) located in Villeneuve d'Ascq (VdA) in the north of France performs solar UV measurements using a spectroradiometer. The site of Briançon in the French Southern Alps is also equipped with a spectroradiometer operated by Interaction Rayonnement Solaire Atmosphère (IRSA). The OMI total ozone column data is obtained from the OMI-TOMS and OMI-DOAS algorithms. The comparison between the TOC retrieved with ground-based measurements and OMI-TOMS data shows good agreement at both sites for all sky conditions with a relative difference for most of points better than 5%. For OMI-DOAS data, the agreement is generally better than 7% and these data show a significant dependence on solar zenith angle. Comparisons of spectral UV on clear sky conditions are also satisfying with relative differences smaller than 10% except at solar zenith angles larger than 65°. On the contrary, results of comparisons of the erythemal dose rates and erythemal daily doses for clear sky show that OMI overestimates surface UV doses at VdA by about 15% and that on cloudy skies, the bias increases. At Briançon, such a bias is observed if data corresponding to snow-covered surface are excluded.

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Solar Ultraviolet Radiation in Pretoria and Its Relations to Aerosols and Tropospheric Ozone during the Biomass Burning Season

Atmosphere ◽

10.3390/atmos12020132 ◽

2021 ◽

Vol 12 (2) ◽

pp. 132

Author(s):

D. Jean du Preez ◽

Hassan Bencherif ◽

Thierry Portafaix ◽

Kévin Lamy ◽

Caradee Yael Wright

Keyword(s):

Ultraviolet Radiation ◽

Biomass Burning ◽

Tropospheric Ozone ◽

Relative Difference ◽

Atmospheric Composition ◽

Future Research ◽

Radiative Effect ◽

Solar Ultraviolet Radiation ◽

The Impact ◽

Solar Ultraviolet

Biomass burning has an impact on atmospheric composition as well as human health and wellbeing. In South Africa, the biomass burning season extends from July to October and affects the aerosol loading and tropospheric ozone concentrations which in turn impact solar ultraviolet radiation (UVR) levels at the surface. Using ground-based observations of aerosols, tropospheric ozone and solar UVR (as well as modelled solar UVR) we investigated the impact of aerosols and tropospheric ozone on solar UVR in August, September, and October over Pretoria. Aerosol optical depth (AOD) and tropospheric ozone reached a peak between September and October each year. On clear-sky days, the average relative difference between the modelled and observed solar Ultraviolet Index (UVI) levels (a standard indicator of surface UVR) at solar noon was 7%. Using modelled UVR—which included and excluded the effects of aerosols and tropospheric ozone from biomass burning—aerosols had a larger radiative effect compared to tropospheric ozone on UVI levels during the biomass burning season. Excluding only aerosols resulted in a 10% difference between the modelled and observed UVI, while excluding only tropospheric ozone resulted in a difference of −2%. Further understanding of the radiative effect of aerosols and trace gases, particularly in regions that are affected by emissions from biomass burning, is considered important for future research.

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