For the fifth time in nine seasons the Champions League final will be contested by teams from the same country.

And for the fifth time in nine seasons, players, officials and supporters will travel en masse to a different country for European football's showpiece event.

After much deliberation, Uefa moved the 29 May match between Manchester City and Chelsea from Istanbul to Porto because of coronavirus restrictions in Turkey, cutting travelling time and cost for fans in the process.

But having taken drastic action because of Covid, have they failed to suitably consider the environmental impact of thousands of supporters flying almost 1,000 miles for a game which could have been played in England?

Fans travelling to those past nine finals have sent an estimated 133m kg of carbon dioxide into the atmosphere - that's the equivalent of burning 734 railway wagons worth of coal, or the contents of 1,761 fully loaded petrol tanker lorries. If those games had been played at a suitable neutral venue, that figure could have been cut to an estimated 27.7m kg - the same as saving the emissions from a whole year's energy use by over 12,600 homes.

"The scale of these avoidable emissions is desperately disheartening," said Andrew Simms, Rapid Transition Alliance co-ordinator and co-director of New Weather Institute.

"Getting real reductions means all of us doing things differently and we need rapid substitutions of clean energy and low impact behaviour, and not a slow, begrudging walk off the carbon pitch."

Why does it matter?

The United Nations secretary general has called on every country to declare a climate emergency amid rising global temperatures and Uefa itself says "if action is not taken to significantly reduce harmful greenhouse gas emissions, the impacts of climate change will continue to put future generations at risk".

As part of that, climate experts and campaigners say we need to avoid or reduce flying because greenhouse gases, produced when fuel is burned, are "the root cause of global warming".

Scientists have warned that such warming could have a catastrophic effect on the planet.

And broadcaster Sir David Attenborough said last week that "the problems that await us within the next five to 10 years are even greater" than those presented by the pandemic.

Manchester City and Chelsea have both been given an allocation of 6,000 tickets for the Champions League final, with the Portuguese government saying they will have to fly in and out of the country on the day of the match.

That number of fans flying on half-full planes from Manchester and London would put roughly the same amount of pollution into the air as you would get from burning the contents of 85 fully loaded petrol tankers.

'Football could take a bold step and others would follow'

Uefa, UK government officials and the Football Association met to talk about Wembley hosting this season's final but it was Covid considerations that were at the forefront of those talks, rather than climate concerns.

Porto was eventually chosen to stage the match as no agreement could be reached on quarantine exemptions for sponsors, VIPs and broadcasters.

"This is a step in the wrong direction," said Elliot Arthur-Worsop, founder of Football For Future, an organisation aiming to promote sustainability through football. "It's a brilliant opportunity to localise this match. If this Champions League final in Istanbul didn't make sense from a Covid, fan or environmental point of view, then what is the motive for holding it in Porto?

"When two teams are set to play on the other side of the continent, this would set an important precedent for what we need to see from the authorities.

"When the argument was being made to move it to England and the venues are there, the fans are there, the willingness is there, the operational logistics are there and the teams are there and then they move it to Portugal instead, that tells me that money is the driving factor.

"That's upsetting from a football fan point of view - after the European Super League announcement, Uefa was the first to criticise the breakaway as a move which came from financial greed. It doesn't take a climate scientist to see that the decision to move the Champions League final to Porto is one being made with the same motive.

"If football took this first bold step to factor the environment into hosting decisions, then other competitions, leagues and teams would follow and that's what we need in this decade. Climate wasn't on the football agenda a few years ago but now those two worlds are colliding and we need to make sure that happens in a way that respects the climate and respects football culture."

Jen Beattie, Scotland and England defender, told BBC Radio 5 Live: "As players you're consumed by your daily business but it's time to open our eyes and play our part in tackling these issues.

"I'm curious as to why the final can't happen in England to stop that foreign travel. Those are the decisions where the higher powers will hopefully make the right ones."
What does Uefa say?

Uefa is a signatory to the United Nations Sports for Climate Action Framework, an initiative to minimise the dangers posed by climate change.

And European football's governing body insists it "places a special emphasis on promoting climate action within the scope of its competitions" and "encourages stakeholders to place due consideration towards environmental sustainability issues that are connected with activities in and around football".

Uefa told the BBC it will offset carbon emissions related to the travel of staff, the teams and supporters for the final, though the legitimacy of offsetting is disputed - and the practice is described as "dangerously misleading"

by Kevin Anderson, Professor of Energy and Climate Change at the University of Manchester.

A Uefa spokesperson said: "In regards to where the finals are staged, Uefa finals are usually reserved for a limited number of countries whose clubs are particularly competitive. However, when the appropriate infrastructure exists and is built also in this perspective, it is fair and due not only to give other fans the possibility of a unique live experience, but also to stage events, which can greatly boost the promotion of football in an entire region.

"That is why Uefa would consider it utterly unfair to exclude certain venues just based on their decentralised geographical position."
Why a flexible approach could make a difference

Having already reacted to the pandemic by moving consecutive Champions League finals - last season's switched to Lisbon and this year's to Porto - could Uefa and other organisations take a more flexible approach to awarding host status for these major events?

Champions League and Europa League final host cities are usually decided around two years in advance, allowing plenty of time for planning and the organisation of logistical issues such as corporate facilities, hotel allocations, transport arrangements and ticketing.

But Simms believes the situation we find ourselves in - the UK parliament declared a "climate emergency" in May 2019 - means organisations must be more nimble and change their approach.

"It's a relatively simple operational decision for Uefa because we know there are a large number of football grounds which have the facilities to host finals like this," he said. "Why would you not have a situation where you have a number of stadiums on call and once you know the finalists, you choose one that would minimise the environmental impact through travel emissions?"

Here is an estimated climate impact of fan travel to the five finals from the past nine years which have featured teams from the same country - and how that could be reduced by choosing a suitable neutral venue between both clubs' home stadiums:
Table showing how C02 emissions from past five finals featuring teas from the same country could have been reduced by choosing a suitable neutral venue

"We know there is a high likelihood of same-country finalists but you could make it part of the design criteria, where you have as one of your fundamental points that you minimise travel distances," added Simms.

"Not only do you make it cheaper and more enjoyable for fans, you reduce the environmental impact so it's a double win. Why would you not do that?"

Additional reporting by Emlyn Begley