Dear Arsenal Football Club,

We write to you as supporters of our beloved football club and/or responsible citizens of the world.

It has come to our attention that Emirates, the airline which acts as Arsenal’s most prominent sponsor, is not on the Airline Contrail Index. This is a list of airlines, now numbering 40, which have taken some form of action on non-CO2 climate impacts (contrails). Contrails, the white lines which form behind airplanes, are now understood by the scientific community and the UK Government to be a major contributor to global warming, with some estimating that non-CO2 impacts constitute up to 66% of aviation’s total climate impact. While there is some uncertainty regarding the exact magnitude of the warming created by contrails, there is a consensus that they have enough of an impact to necessitate immediate action, and that the greatest risk associated with contrails is inaction.

Emirates, in spite of being the world's fourth-largest airline in terms of Available Seat Kilometres and the second-largest in terms of freight tonne-kilometers flown, has not even publicly acknowledged the climate effects of contrails, nor has it joined with other major airlines, like British Airways​, American Airlines and Etihad Airways in:

1. Amending sustainability webpages to be transparent about the non-CO2 impacts the airline is responsible for.
2. Collaborating on, or supporting, research projects on contrails.
3. Participating in contrail mitigation research and contrail avoidance trials, which have shown potential to be effective (reducing the climate effects of contrails by 69%). Emirates operates many flights over the Indian Ocean and South Atlantic, where there are relatively low levels of air traffic and so would be ideal places for contrail avoidance manoeuvres.

This is made all the more regrettable by the fact that Emirates was ranked as 9th in the world for contributing the most warming contrails, according to the Contrail Opportunity Index produced by Estuaire.com. This index also points out that the Emirates flight Singapore Changi (WSSS) → Dubai International (OMDB) is the 2nd worst for producing warming contrails of any flight globally.

Because of this, we ask that Arsenal makes (at the very least) the public acknowledgement of the climate effects of contrails by Emirates, by the end of 2026, a condition of ongoing collaboration between the two organisations. Transparency and action on contrails is necessary, urgent and possible.

Yours sincerely,

The undersigned