EJERS, European Journal of Engineering Research and Science Vol. 3, No. 10, October 2018 DOI: http://dx.doi.org/10.24018/ejers.2018.3.10.903 21 Abstract—The spatial distribution of Erythemal Ultraviolet Dose Rate (EUV) at noon in mW/m 2 observations gotten from the Ozone Monitoring Instrument (OMI) are presented over Egypt covering the geographical domain (22.5°–31.5°N, 25.5°– 35.5°E) during twelve years from 2005 to 2016. With the end goal of mapping contour, with a spatial resolution of 1°×1° the results illustrated by monthly, seasonally and all period contour maps indicate high similarity of EUV in all years. Monthly correlation (R 2 ) relationship between EUV and Latitude also estimated in simple linear form. High R 2 was found in December and January (97%) were low one was found in July (53%). In the frame of the variability, Egypt was considered as an average area; the box-whisker plots were created for average monthly and annual values of EUV. The monthly mean of EUV values are lower in the winter months (December to February) 116.17±2.30 mW/m 2 compared to those in the summer months (June to August) 282.36±2.87 mW/m 2 . The annual mean of EUV values are lower in 2015 (204.15±60.41 mW/m 2 ) and higher in 2013 (213.13±60.34 mW/m 2 ). Index Terms—Contour Maps; Egypt; Erythemal UV Dose Rate; OMI Satellite Data; Variability. I. INTRODUCTION Recently, the sunburn in human’s skin (erythema) is the destructive effect that has gotten most attention. Thus, this impact is usually quantified the weighing solar UV radiation with the erythemal spectral response, so it resulting in the ultraviolet erythemal radiation (EUV). Erythemal UV was evaluate of the potential for harmful biological effect causes by solar ultraviolet radiation also it is an estimate of the day by day integrated UV irradiance, calculated for susceptibility of the Caucasian skin to erythema (sunburn). Also it is called Erythemal Daily Dose, Erythemal Dose Rate, Erythemal UV Daily Dose and Erythemal UV Exposure. The curve adopted in 1987 by the Commission Internationale del’Eclairage (CIE) [1] is currently recommended as a standard erythemal action spectrum [2]. So, the variable EUV is seen as international standard for deciding the risk associated to UV radiation. The effectiveness of solar radiation in causing a specified biological effect, or its biologically effective irradiance, erythemal UV (EUV), can be determined once the solar spectral radiation and the action spectrum of a specified biological response are known across a predetermined waveband [3]. Erythemally weighted solar radiation (EUV) ranges from 280 to 400 nm. As the weighting function [4] Published on October 8, 2018. E. F. El-Nobi was with South Valley University, Qena, Faculty of Science, Department of Physics, Egypt (e-mail: eman.fouad@sci.svu.edu.eg). allows only for a marginal effect of higher wavelengths, the properties of EUV are well comparable with Ultraviolet-B (UV-B) radiation (280–320 nm). In this manner, biologically effective terrestrial solar irradiance is the result of the power of the solar spectrum and the action spectrum in question. The area under the resultant curve is the biologically effective irradiance (EUV) and may be given as:   400 280 ) ( ). (     d E EUV (1) where ) ( E is the spectral irradiance distribution (W/m 2 .nm), ) (  is the relative effectiveness of radiant energy at that wavelength in producing the specified biological effect (unit less), or its action spectrum and  d is the band width (nm) of the measurement interval over the wavelength range 280–400 nm [5]-[12] . The standard erythema action spectrum gives a global accepted concept of the erythema due to UV effective ness wavelengths region of the spectrum. Since the 1990s, UV Index (UVI) has been acquainted as a helpful way to inform the public about the possibly destructive impacts of ultraviolet radiation and it is directly calculated using EUV radiation [13]-[16]. UV index is unit less number and calculated by EUV, has units of W/m 2 , and multiplying the result by the constant equal to 40 m 2 W −1 [17]: EUV UVI   40 (2) Information about the EUV radiation is therefore very interesting and useful for experts from various fields. In recent years, study of the spatial distribution and temporal variations of EUV has attracted considerable attention around the world such as; Slovakia [18], Thailand [19], Tibetan Plateau [20]-[21], China [22] and Peninsular Malaysia [23]-[24]. Therefore, the aim of this publication is to create maps of the Erythemal Ultraviolet Dose Rate daily noontime for the whole territory of Egypt (22.5°–31.5°N, 25.5°–35.5°E), employing available satellite data derived from the Ozone Monitoring Instrument (OMI) during thirteen years from 2005 to 2016. The spatial distribution of Erythemal Ultraviolet Dose Rate expressed in map form can be useful for future local studies on UV index in order to inform the public about the possible harmful effects of UV radiation over-exposure impact on the human beings. In section II, the instrumentation and the data used in this paper are described. Finally, in section III describes the results followed by its discussion. Erythemal UV Dose Rate Spatial Distribution using Ozone Monitoring Instrument Satellite Data over Egypt Eman F. El-Nobi