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arXiv · 1305.0615

Astronomical seeing and ground-layer turbulence in the Canadian High Arctic

P. Hickson·R. Gagne·T. Pfrommer·E. Steinbring
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Abstract

We report results of a two-year campaign of measurements, during arctic winter darkness, of optical turbulence in the atmospheric boundary-layer above the Polar Environment Atmospheric Laboratory in northern Ellesmere Island (latitude +80 deg N). The data reveal that the ground-layer turbulence in the Arctic is often quite weak, even at the comparatively-low 610 m altitude of this site. The median and 25th percentile ground-layer seeing, at a height of 20 m, are found to be 0.57 and 0.25 arcsec, respectively. When combined with a free-atmosphere component of 0.30 arcsec, the median and 25th percentile total seeing for this height is 0.68 and 0.42 arcsec respectively. The median total seeing from a height of 7 m is estimated to be 0.81 arcsec. These values are comparable to those found at the best high-altitude astronomical sites.

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P. Hickson, R. Gagne, T. Pfrommer, E. Steinbring. 2013-05-03. Astronomical seeing and ground-layer turbulence in the Canadian High Arctic. https://doi.org/10.1093/mnras%2Fstt729

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