Observations and model calculations of direct solar UV irradiances in the Schirmacher region of east Antarctica

• Main Authors: Ghude, SD, Singh, S, Kulkarni, PS, Kumar, A, Jain, SL, Singh, R, Arya, BC
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Taylor & Francis 2008
• Subjects: Meteorology and Climatology; East Antarctica; Antarc*; Antarctica
• Online Access: http://moeseprints.incois.gov.in/1828/; http://www.tandfonline.com/doi/pdf/10.1080/01431160802108505

Measurements of direct UV irradiances (using a MICROTOPS II Sunphotometer) carried out from a high-latitude site, Antarctica are presented. The instantaneous irradiances at 305 ± 0.9, 312 ± 0.9 and 320 ± 1.0 nm during a no-ozone-hole (13 December 2004) and an ozone-hole (4 October 2004) period have been observed to be about 0.031, 0.150 and 0.299 W m-2 and 0.010, 0.049 and 0.102 W m-2, respectively at local noontime. The observations of the direct UV irradiances at 305 ± 0.9, 312 ± 0.9 and 320 ± 1.0 nm are compared with tropospheric ultraviolet visible (TUV) radiation transfer model calculations. The model estimate shows that, during the ozone-hole period, a loss of ozone of the order of 44 leads to an increase in irradiance of the order of 410, 90 and 25 at 305 ± 0.9, 312 ± 0.9 and 320 ± 1.0 nm, respectively. The relationship between change in UV irradiance due to a change in column ozone is obtained using a TUV model and irradiances thus estimated from this relationship are found to compare well with the observed irradiances.