UV intensity near the AOS and OSF sites in northern Chile was measured with handheld UVA and UVB radiometers and was compared with that taken at Socorro AOC, Nobeyama, and Mitaka. Typical UVA opacity was about 0.4 at Pampa La Bola near the AOS site, about 0.6 both at San Pedro de Atacama near the OSF site and at Nobeyama, and about 0.7 at Mitaka (best conditions), respectively. The UVA intensity toward the Sun measured at Pampa La Bola near the sunset (elevation ~20 degrees) was still comparable with the highest value recorded at Mitaka. The difference becomes even more outstanding in UVB. The UV Index, which chiefly reflects UVB intensity, measured with a handheld UVB radiometer is in reasonable agreement with that predicted with the satellite data, and both consistently indicate that the UVB is extremely high at the AOS and OSF sites. The UV Index typically exceeds 7 (high) for 6 hours near the AOS site.
View a pdf version of ALMA Memo #448.
Last modified: 2003-03-24
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