Average surface albedo measurements in the UV, IR, and TSR on the Holy Mosque and places in Makkah, Saudi Arabia

Abstract

Average albedo values were measured at three broad wavebands; UV region (295 - 385 nm), Total Solar Radiation, TSR, (305 - 2800 nm), and IR region (3500 - 50000 nm), over different surfaces in the Holy Mosque and Places in Makkah (21°.25 N, 39°.49 E). The Eppley Laboratory Radiometers of TUVR and PIR were used for UV and IR measurements respectively, while Kipp & Zonen Pyranometer of CM3 was adopted for the TSR observations. Measurements were performed during two different periods (summer 28/7-10/8/2004 at Holy Mosque and winter 18-30/1/2005 at Holy Places). Summer measurements showed that the average surface albedos of the Holy Mosque white marbles were 0.45, 0.70 and 1.14 at UV, TSR and IR regions respectively. These values have decreased to 0.12 and 0.18 at UV and TSR regions respectively over the Holy Mosque brown marbles. However, the average albedo value has increased to 1.38 at IR region due to the large Longwave radiation emission from the brown marble surfaces. The albedo values of the Holy Mosque red carpets were determined. The average albedo values were also measured over the Holy Places surfaces (18 m) of pilgrimage, (Muna and Arafat sites) during winter 2005. The observed average surface albedo values over Arafat selected area were 0.00, 0.22 and 1.18 at UV, TSR and IR regions respectively. The average albedo values over Muna selected area and Muna tents were also presented. The effect of clouds and solar zenith angle (SZA) on the measured albedo were investigated in this study.