The first big international gathering of the year is the annual meeting of the World Economic Forum in the Swiss ski resort of Davos. Politicians, academics, businessmen and a smattering of billionaires make up the guest list, while campaigners and activists lobby on the fringes. So what have we learned from their week in the snow?

1 Davos has lost its mojo

Love him or hate him, Donald Trump created a buzz at the 2018 annual meeting, but this year the atmosphere was flat. Ken Rogoff, a Harvard economics professor and Davos regular, said he could not recall the mood being so muted. Without Trump, Xi Jinping of China or Vladimir Putin, Davos lacked a headline act. The format – panels of experts discussing the world’s problems – looks tired.

2 Unlikely showstoppers

The stars at this year’s WEF had a distinctly un-Davos feel about them. The broadcaster Sir David Attenborough (a sprightly 92) and climate activist Greta Thunberg (a resolute 16) both used the forum’s spotlight to promote climate activism (and in Sir David’s case his new Netflix documentary too).

Prince William and the New Zealand PM, Jacinda Ardern, were a hot ticket and there was an unseemly scramble to get into their discussion session on mental health. The Duke of Cambridge revealed he hadn’t been able to get any celebrities to sign up to help launch the Heads Together campaign fronted by him, his wife and his brother. He criticised the British stiff-upper-lip approach of the wartime generation, and said it was partly to blame for the stigma around mental health problems.

3 Climate change is unavoidable but have delegates really got the message?

Delegates who took the trip up Davos’s funicular railway met Arctic scientists warning of a climate change catastrophe unless urgent action is taken to “bend the curve” on rising greenhouse gas emissions.

Phasing out burning coal would be a good start, but environmentalists were disappointed when Angela Merkel said Germany would need coal for “a certain time” (and more Russian gas otherwise).

Davos, meanwhile, was gridlocked with limos all week, suggesting that CEOs need to walk the walk as well as talk the talk. Or, indeed, just walk.

4 Unease about the global economy

Davos has three settings. There are years, such as 2009, when the attendees are panic-stricken. There are years, such as 2007, when they are insufferably bullish. And there are years in between, such as this one. There was concern about the recent weakness of the global economy – but not that much. If a recession is in the offing, Davos has not realised it yet.

5 Growing concern about Brexit

Philip Hammond stood in for Theresa May this year and the chancellor had a series of meetings with business chiefs and policymakers in an attempt to reassure them that the government was doing its utmost to avoid a no-deal Brexit on 29 March. He would have needed a tin ear not to have picked up on the growing business worries.

His key message was that the vote to leave had to be respected – but that a no-deal Brexit would be a betrayal of the hopes for a better future of those who voted leave.

Facebook Twitter Pinterest Zurich Insurance’s blue bobble hat giveaway proved a hit. Photograph: @Zurichinsurance/Twitter

6 The Davos bobble hat

Even the global elite like a freebie, and few giveaways are more popular than the blue Davos bobble hats, sponsored by Zurich Insurance, and available from a special hole-in-the-wall bobble dispenser outside the conference centre.

So much more than a mere beanie, they have a discreet logo which can advertise the wearer’s importance on the school run or a family ski holiday. Hundreds are handed out every year and by Thursday they had to post a sign saying they’d run out – but to come back next year.

7 Nobody likes Davos

While everyone who’s anyone is expected to be at Davos, few seem to really enjoy it, and the four days can be a slog. Politicians are expected to come back with some tangible deals, lest they be criticised for simply quaffing champagne. Many of the corporate elite spend their days in back-to-back meetings with clients and investors: one executive said he had attended no fewer than 17 in one day.

But, as Oscar Wilde might have said: there’s only one thing worse than being invited to Davos – and that’s not being invited.

8 Populism hits the world stage

Trump may have been missing out on the action, but the latest poster-boy for rightwing populism, Jair Bolsonaro, made his international debut. The new Brazilian president delivered a six-minute pro-business speech, promising to balance economic growth with preserving his country’s unique environment. That, however, prompted alarm among activists worried about the environmental threat.

9 Hierarchy is everything

The first thing to learn at Davos is the tiered badge system. It gives the top boss class – who get white badges with a hologram – an easy way to decide if you’re worth talking to. Pesky journalists, for the record, are highlighted with yellow badges.

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There’s a hierarchy of dinners and parties too. Organisers trying to impress invite celebs and politicians to parties in swanky buildings. JP Morgan had a very popular bash at the Kirchner Museum while Aberdeen Standard set up a posh scotch whisky bar. But the best parties are often the ones you don’t know about.

10 And now the good news…

Carping aside, there was some good news out of Davos. Seven top businesses backed the new Partnership for Global LGBTI Equality, for example, while 25 are supporting a new recycling drive.

Japan’s prime minister, Shinzō Abe, pledged action on global data governance, and the UK pushed on antimicrobial resistance. The WEF also brought leaders together to discuss “key global faultlines” including the western Balkans and Syria. All areas where progress was welcome.