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arXiv · 2212.08093

Global Extinction: Combined Gemini North and South GMOS Photometry Relative to the Gaia Catalog, and Long-Term Atmospheric Change

Eric Steinbring
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Abstract

Effects of long-term atmospheric change were looked for in photometry employing the Gemini North and South twin Multi-Object Spectrograph (GMOS-N and GMOS-S) archival data. The whole GMOS imaging database, beginning from 2003, was compared against the all-sky Gaia object catalog, yielding ~10^6 Sloan r'-filter samples, ending in 2021. These were combined with reported sky and meteorological conditions, versus a simple model of the atmosphere plus cloud together with simulated throughputs. One exceptionally extincted episode in 2009 is seen, as is a trend (similar at both sites) of about 2 mmag worsening attenuation per decade. This is consistent with solar-radiance transmissivity records going back over six decades, aerosol density measurements, and more than 0.2 deg C per decade rise in global air temperature, which has implications for calibration of historic datasets or future surveys.

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Eric Steinbring. 2022-12-15. Global Extinction: Combined Gemini North and South GMOS Photometry Relative to the Gaia Catalog, and Long-Term Atmospheric Change. https://arxiv.org/abs/2212.08093

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