Radiation measurements were carried out during a research cruise of theN. Palmerin August and September 1993, from the tip of South America to Antarctica. As the measurements were carried out on a moving platform their validity had to be confirmed. This was undertaken for hourly data. Some of the main results are as follows:The radiation levels changed substantially during the cruise, as both latitude and season changed. Daily values of global, UV-A and UV-B radiation are presented.The mean value of the clearness indexKt(total transmissivity) was found to be 0.44. This is rather a low value, however, the cloudiness was high (mean value 78). The clearness index increased with decreasing cloudiness from 0.41 for overcast conditions to 0.62 for clear sky conditions. Individual daily values varied even more, but always ranged between 0.2 and 0.8.The UV-A and UV-B radiation levels were related to the global radiation. However, correlation coefficients improved substantially when the analysis was carried out for different cloudiness classes. Clouds produced the largest reduction in global radiation and reduced UV-A and then UV-B to a lesser extent.As can be deduced from the previous bullet point therelativeintensity of the UV radiation increased with cloudiness. This was more pronounced for UV-B than for UV-A.Ozone concentrations during the trip varied between 160 to 290 DU (Dobson Units). We passed under the “Antarctic ozone hole” several times during the cruise.UV-B radiation levels were affected by ozone levels and cloudiness. A 3-dimensional presentation is presented for UV-B versus ozone and cloudiness.UV-B radiation levels were, on average, more than double the average whilst under the “Antarctic ozone hole”, whereas UV-A radiation levels were hardly a
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