Influences of the clearness index for the whole spectrum and of the relative optical air mass on UV solar irradiance for two locations in the Mediterranean area, Valencia and Cordoba

Ultraviolet solar irradiance (290-385 nm) was analyzed in Valencia and Cordoba, Spain, during 1996-1997. Its relation to the instantaneous atmospheric clearness index k t , the relative optical mass m r , the time of the year, and the total or global irradiance on a horizontal surface was established. The maximum values of UV irradiance for each optical mass exponentially diminished with the optical mass, thus for Cordoba and Valencia, G uv = 62.23 m -1.34 r and G uv = 52.84 m -1.30 r , respectively. The UV irradiance in Cordoba represented 4.2% of the total irradiance while in Valencia this percentage was 4.9%. In the case of cloudy days (k t < 0.4), these percentages ranged between 5.6% and 6.8% in Valencia and between 5.1% and 5.5% in Cordoba.

[1]  S. Dilmac,et al.  A study of solar ultraviolet radiation at Istanbul , 1996 .

[2]  Benjamin Y. H. Liu,et al.  The interrelationship and characteristic distribution of direct, diffuse and total solar radiation , 1960 .

[3]  J. Orgill,et al.  Correlation equation for hourly diffuse radiation on a horizontal surface , 1976 .

[4]  J. Staehelin,et al.  Influence of snow and clouds on erythemal UV radiation: Analysis of Swiss measurements and comparison with models , 2000 .

[5]  C. Riordan,et al.  Influences of atmospheric conditions and air mass on the ratio of ultraviolet to total solar radiation , 1990 .

[6]  Sami D. Alaruri.  The empirical relationship between global radiation and global ultraviolet (0.290–0.385) μm solar radiation components , 1990 .

[7]  M. Iqbal.  An introduction to solar radiation , 1983 .

[8]  mCkenzie.  APPLICATION OF A SIMPLE MODEL TO CALCULATE LATITUDINAL AND HEMISPHERIC DIFFERENCES IN ULTRAVIOLET RADIATION , 1991 .

[9]  Sethu Raman,et al.  Effects of clouds and haze on UV‐B radiation , 1996 .

[10]  D. Häder.  Impact on Marine Ecosystems , 1997 .

[11]  Global Ozone Change and Possible Climate Implications , 1997 .

[12]  M. A. Mosalam Shaltout,et al.  Ultraviolt solar radiation over Egypt , 1994 .

[13]  K. Stamnes,et al.  Measurements of solar u.v., visible and near i.r. irradiance at 78° N , 1989 .

[14]  A. Khogali,et al.  A study of solar ultraviolet radiation at Makkah solar station , 1992 .

[15]  Stuart A. McKeen,et al.  Effect of anthropogenic aerosols on biologically active ultraviolet radiation , 1991 .

[16]  A. T. Young,et al.  Revised optical air mass tables and approximation formula. , 1989, Applied optics.

[17]  M. Blumthaler,et al.  A comparison of ultraviolet radiation measured at an Arctic and an alpine site , 1991 .

[18]  B L Diffey,et al.  Solar ultraviolet radiation effects on biological systems. , 1991, Physics in medicine and biology.

[19]  M. P. Utrillas,et al.  MEASUREMENT AND ANALYSIS OF ULTRAVIOLET SOLAR IRRADIATION IN VALENCIA, SPAIN , 1996 .

[20]  José A. Martínez-Lozano,et al.  Comparison of global ultraviolet (290–385 nm) and global irradiation measured during the warm season in valencia, spain , 1994 .

[21]  P. Németh,et al.  Effect of weather conditions on UV-B radiation reaching the earth's surface , 1996 .

[22]  Jerónimo Lorente,et al.  Influence of urban aerosol on spectral solar irradiance , 1994 .

[23]  W. Beckman,et al.  Diffuse fraction correlations , 1990 .

[24]  Christos Zerefos,et al.  Spectral measurements of solar UVB radiation and its relations to total ozone, SO2, and clouds , 1993 .

[25]  M. Molina,et al.  Absolute absorption cross sections of ozone in the 185- to 350-nm wavelength range , 1986 .

[26]  J. Duffie,et al.  Estimation of the diffuse radiation fraction for hourly, daily and monthly-average global radiation , 1982 .

[27]  M. A. Elhadidy,et al.  Ultraviolet solar radiation at Dhahran, Saudi Arabia , 1990 .

[28]  C. Rao,et al.  Near ultraviolet radiation at the earth's surface: measurements and model comparisons , 1984 .

[29]  Ellsworth G. Dutton,et al.  UV measurements at Mauna Loa: July 1995 to July 1996 , 1997 .