Image copyright Getty Images Image caption Last month Switzerland's Pizol glacier, which has lost 80% of its volume since 2006, was remembered in a "funeral march"

Climate change has risen to the top of Switzerland's political agenda and observers are eyeing a possible "green tsunami" in 20 October elections.

For decades Switzerland has been dominated by four main parties; the Swiss People's Party, the Social Democrats, the FDP liberals and the Christian Democrats.

But as the glaciers melt, the president of the Green party's youth wing sees an opportunity.

"This is our year," says Maja Haus.

"There is a climate crisis, and for the Green party this is a huge chance, because we have the answers to this problem: 2019 will be the climate elections."

How big is the green wave?

In the run-up to the vote the Green party has overtaken the Christian Democrats in the opinion polls. If those polls translate into seats, the Christian Democrats' place in Switzerland's seven-member government looks shaky.

Including the more fiscally conservative Green Liberals, who are also polling well, greens could be a significant force in parliament. Latest opinion polls give them a combined 18% of the vote, a comfortable second place.

How are Greens doing in Europe?. [ 74 out of 751 seats in European Parliament ],[ 20.5% of German vote in May 2019 Euro elections ],[ 16% in Finnish European vote ],[ 13.5% in French EU vote ],[ 14% in Austrian election on 29 September ], Source: Source: EP/ORF, Image: Green party poster in Berlin, May 2019

But this election is about more than just a rise in support for green parties. "There was a lot going on in Switzerland during the last year," says Fabian Molina, who at the age of 29 is already a member of parliament for the Social Democrats.

"We had a women's strike, we had a climate strike, people want change."

In June this year hundreds of thousands of women across Switzerland took to the streets to call for equal pay and conditions, and an end to discrimination.

Video caption Socialist MP Flavia Wasserfallen told Imogen Foulkes in June why women were taking to the streets

It was, the Swiss Trades Union Federation said, the biggest political demonstration Switzerland had ever seen.

All year climate strikes have been taking place, culminating in a huge rally in Bern in September, with 100,000 people taking part.

Image copyright Getty Images Image caption Climate change could cause the biggest glacier in the Alps, the Aletsch in Switzerland, to vanish by the end of the century

The protests are a sign, says political analyst Barbara Perriard, that voters are energised, and some voters in particular.

"We have a lot more women candidates this year," she says. "An increase of 40% on the last elections. And we have more than 450 candidates who were not eligible to vote in 2015, so that means young citizens want to participate in politics."

How has climate change influenced young candidates?

Among those standing is 21-year-old Alicia Badnod. For her, climate change and the environment are the top issues.

Image caption Alicia Badnod is not standing for the Greens but puts climate change at the top of her agenda

She is not standing for the Green party, but rather as an independent because, she believes, young people have lost '"hope in the mainstream parties".

Kelmy Martinez, also 21, is taking a different approach.

"Climate has no borders, the environment is global. This is not a question of whether you are in France or Germany or Switzerland. You will face the climate crisis", Source: Kelmy Martinez, Source description: Social Democrat candidate, Image: Kelmy Martinez, Social Democrat candidate

He too puts climate at the top of his political priorities, but he is standing for the Social Democrats, one of Switzerland's oldest parties, and currently the second biggest in parliament.

What is striking is that key issues that have mobilised Swiss voters in the past, specifically immigration, and relations with the European Union, are just not cutting through with these young people.

Alicia remembers being put off, during the last election in 2015, by the focus, particularly from the right-wing Swiss People's Party, on the dangers of immigration.

"It's easier to tell someone you are scared," she explains, "and then to tell them we will make your fears disappear, but the reality of Europe right now is multicultural."

Is Swiss populism in decline?

The Swiss People's Party remains the largest in parliament. It has campaigned for over a decade on two key messages: restrictions on immigration and asylum seekers, and limiting non-EU member Switzerland's ties with Brussels.

When President Donald Trump's former adviser Steve Bannon came to Zurich last year, he praised Switzerland, and the Swiss People's Party, for being the cradle of populism. But this year, even among older voters, other issues seem more important: the cost of healthcare, pensions and, again, climate change.

When the People's Party unveiled an eye-catching campaign poster, showing a perfect Swiss red apple being eaten by worms, one of which wore the blue flag and gold stars of the EU, there was widespread criticism, even from within the party.

Still the party hopes to retain a big share of the vote and has, some would say belatedly, come out with a policy on climate change, one that will appeal to its traditional supporters in the farming community.

"What we believe would be beneficial for the climate is that people buy local," says People's Party member of parliament Andreas Ott. "And buy seasonal, that is one of the main levers for the Swiss to reduce our climate footprint."

Who will win?

When all the votes are counted on Sunday, there will be, as ever in Switzerland, no outright winner. The entire system is designed, explains political scientist Andreas Ladner, to give all views a voice, but no single party too much power.

Image copyright Getty Images Image caption Green candidates are aiming to capitalise on Swiss worries about climate change

"If you want to understand the Swiss system you have to know this culture. We are a small country. We don't like strong leaders. It is more important to integrate everybody, into government, into political responsibilities."

There will be no green tsunami, then, but, if the polls are right, a drop in votes for the Swiss People's Party, and an increase for the Greens.

No big overnight change, but a gradual shift towards more environmental policies. Many eager new members of parliament, and the old, will have to work together, to find compromises. It's the Swiss way, and suggests Andreas Ladner with a wry smile, it might "be an example for other countries".