Attenuation of ultraviolet irradiance in North European coastal waters

• Main Authors: Niels K. Højerslev, Eyvind Aas
• Format: Article
• Language: English
• Published: Elsevier 2001-06-01
• Series: Oceanologia
• Subjects: UV irradiance; Attenuation; Coastal waters; Fjords; Straits; Optical properties
• Online Access: http://www.iopan.gda.pl/oceanologia/43_2.html#A0

A total of 439 measurements of downward ultraviolet irradiance in North European coastal waters have been analysed, half of which have been taken from other authors. The depths <i>Z</i>(10%) where the irradiance is reduced to 10% of its surface value vary by one order of magnitude in the open coastal waters, both at wavelengths of 310 nm (0.3&#8211;10.4 m) and 380 nm (1.2&#8211;13.0 m). In the fjords and estuaries the depth ranges are reduced to 0.08&#8211;6.1 m at 310 nm and 0.18&#8211;7.7 m at 380 nm. Mixing with saline ocean waters can increase these light penetration depths to more than 10 m, while river water can reduce them to a few centimetres.