Estimating carbon emissions at CFHT: a first step toward a more sustainable observatory

Abstract. As the crisis of climate change affects more people every year and leads to more severe weather patterns with unprecedented socio-economical consequence, all actors on the planet need to understand their responsibility and contribute to solving this generational problem. To tackle this issue, individuals and corporations first need to assess their carbon footprint, which then represents the groundwork for the future implementation of significant changes required to reduce that footprint. We present the carbon emissions attributed to the Canada–France–Hawaii Telescope (CFHT) for the year 2019. We partnered with CarbonBuddy and followed their method to break down the greenhouse gas (GHG) emissions of various activities at CFHT for the entire year of 2019: air travel in and out of state, ground vehicle usage, electricity consumption, and other fossil fuel utilization. The total GHG emissions of CFHT for the year 2019 amount to about 749 tons of CO2 equivalent, which corresponds to more than 16 tons per employee. About 63% of the emissions are related to electricity usage at the summit facility, about 25% to out-of-state travel, about 6% to the use of our fleet of vehicles, and about 5% to electricity usage at headquarters. We show that significant improvements have occurred in the recent past at CFHT, with the installation of solar panels and a remarkable reduction in electricity consumption at headquarters. We list suggestions to further decrease the GHG emissions in the short to long term: offset current emissions by support local projects, invest in more efficient equipment, and establish environmentally friendly habits. The fundamental work presented will facilitate the official planning at CFHT for a drastic reduction in GHG emissions with the goal to meet the objectives laid out in the 2015 Paris Accord. It will also support the design of the Maunakea Spectroscopic Explorer (MSE), the future transformation of CFHT, and allow the project to seize this opportunity and incorporate the fight against climate change as one of its core missions. By choosing to implement those changes, CFHT and MSE can become part of the solution to climate change and lead the way, locally and in the world of astronomy.