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Abstract Global solar UV measurements performed with high-resolution SUV-100 spectroradiometers in Antarctica and Alaska are compared with results of the radiative transfer model UVSPEC/libRadtran. The instruments are part of the National Science Foundation's Office of Polar Programs (NSF/OPP) UV monitoring network, and are located at the South Pole (90 degree(s)S), McMurdo (78 degree(s)S), Palmer Station (65 degree(s)S), and Barrow, Alaska (71 degree(s)N). A new algorithm to retrieve total column ozone from the ratio of measured and modeled UV spectra is presented, which is then used to uncover biases in column ozone data from different sources (Earth Probe TOMS Version 7, Dobson, GOME, TOVS) at the previously mentioned high-latitude locations. The analyses suggest that EP/TOMS overestimates total column ozone at all Antarctic sites by 4-10%, which is consistent with recent findings reported elsewhere. SUV-100 and Dobson total column ozone measurements at the South Pole, Barrow and McMurdo agree to within +/- 1.5%, +/- 2%, and +/- 1%, respectively. GOME measurements at Palmer and McMurdo Station are 2% and 6% lower than the SUV-100 data. TOVS ozone values show in general a larger deviation. The data further reveal that ozone and temperature profiles used in the model have an important influence, particularly at low sun elevations. This is quantified by comparing the UV measurements with model calculations using either standard profiles or actual profiles measured by balloon sondes. When using Dobson ozone measurements and actual ozone profiles, and correcting SUV- 100 UV measurements for the cosine error of the entrance optics, spectral clear-sky measurements typically agree with model results to within +/- 5% for solar elevations greater than 5 degrees.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.