It is that time of the year when world leaders, business and economic elite and civil and cultural society figure-heads all converge on the Swiss mountain resort of Davos for the World Economic Forum's annual meeting.

Here are five things to know about the event, which opens formally later today:

1. President Trump is to attend

Last year US President Donald Trump was due to attend Davos, but cried off at the last minute because of the controversy around the shutdown of the federal government.

This year we are told he is due to attend again, with an address pencilled in for 11.30am local time (10.30am Irish time) tomorrow. It is not clear yet what he is likely to talk about.

World trade issues are a strong possibility given the forum in which he will be speaking, and the US's recent progress in achieving phase one of a new trade deal with China.

Also, climate change will be high on the event's agenda, so it may be politically difficult for him to dodge it.

Political tensions in the Middle East may also come up, although its perhaps interesting to note that the Iranian government delegation that was due to attend has pulled out.

One thing he probably won't speak about is his own impending impeachment trial which is due to get underway in the Senate in Washington this week.

Indeed, it is perhaps not beyond the bounds of possibility that Trump may yet pull out of Davos in order to be around for the trial.

However, he may also decide to send a signal to Democrats about his views of their efforts to get him removed from office, by continuing about his normal presidential business. In Switzerland.

2. The Irish Government won't be there

While the US government will be there in force (Steve Mnuchin and Robert Lighthizer will also be in town), the Irish Government will be conspicuous by its absence.

Taoiseach Leo Varadkar, Tánaiste Simon Coveney and Minister for Finance Paschal Donohoe were all named on early participant lists.

However, in the past week it is understood they all opted not to travel, because of the start of the General Election campaign.

The decision means it will be the first time since Fine Gael came into Government in 2011 that Ireland hasn't been ministerially represented at Davos.

It is a bit of a surprise, given the significant issues that will be up for discussion at this year's meeting, including trade tensions, Brexit, climate change and reform of the international tax regime, which may hit Ireland hard in the pocket in years to come.

The decision left the IDA with a bit of a last minute problem, as the Taoiseach was due to be the host at its annual dinner for business leaders and other partners with an interest in foreign direct investment in Ireland.

However, it is understood that Ireland's Phil Hogan, EU Commissioner for Trade, will attend, not on the Irish Government's behalf of course, but in the context of his new European brief.

3. Climate front and centre

It will come as no great shock to hear that climate change will be front and centre at Davos 2020. The great global issue of our time, it would be amazing if it weren't.

"Stakeholders for a Cohesive and Sustainable World" is the laudable hem of this year's event. Greta Thunberg, the Swedish teen climate activist will likely be the big headline grabber on the subject.

Known for not mincing her words and for putting pleasantries to one side in such settings, she can be expected to make her points forcefully to those leaders in attendance.

But she won't be alone. Other notable attendees from the sustainability space will include Marco Lambertini, Director-General of the World Wildlife Fund, Jennifer Morgan, the Executive Director of Greenpeace International, former US Vice-President Al Gore, Frans Timmermans, the Executive Vice-President for the European Commission's Green Deal and many more.

A raft of reports are also set to be released on the topic. The World Economic Forum has gone out of its way this year to talk up the sustainability efforts it has gone to in planning this year's event after stinging criticism last year of the hypocrisy of leaders talking about climate change, but traveling there by private jet.

It claims Davos 2020 will be carbon neutral as a result of the offsetting measures it has put in place to make up for the many hundreds of aircraft that will fly specially into the area over the week, as well as the other gas guzzling consumption that goes along with such a meeting.

These measures include using locally-sourced food suppliers, introducing alternative sources of protein to reduce meat consumption, sourcing 100% renewable electricity, reducing or eliminating the use of materials that cannot easily be recycled or re-used, such as carpets and introducing more electric vehicles.

It has also asked all participants to commit themselves to achieving net zero carbon emissions by 2050 or earlier.

Climate change demonstrations in the vicinity of Davos seem likely though. Yesterday, climate activists set off on a three-day hike from Landquart in eastern Switzerland to Davos to draw attention to global warming.

They will be let as close as neighbouring town Klosters, but won't be allowed to bring their message right to the heart of Davos.

UK Prime Minister Boris Johnson (L) and Taoiseach Leo Varadkar will not be attending the forum

4. Where are the British?

If everyone else is going to Davos, then the British will be notable absentees. Prime Minister Boris Johnson has banned his ministers from attending, a Downing Street source said last week.

He had promised to run a "people's government" that would deliver Brexit and repay trust placed in him by voters, particularly traditional Labour ones, and apparently "champagne with billionaires" doesn't fit with this narrative or image.

Chancellor Sajid Javid has, however, been given a pass on the issue. He will come on Thursday to attend a lunch being hosted by the Confederation of British Industry and he will also take part in a panel on the global economy on Friday, the programme states.

But it doesn't just appear to be the British government who are, for the most part, staying away. According to the Telegraph newspaper the number of British delegates at this week's summit is the lowest for at least a decade.

Just 239 UK attendees will be there, down 30% on the peak of 339 in 2011. Quite why the Brits are staying away is not clear.

Perhaps they know something the others don't, or maybe they are cannily hoping that while all their competitors are living it up on the piste they can pull off some spectacularly clever deals under the radar. Or maybe, they are just too busy thinking about and preparing for Brexit.

5. Where are the women?

Davos has long been "male, pale and stale". Indeed in 2004 Samuel P. Huntington, a Harvard based political scientist, wrote a paper about elites and "an emerging global superclass of Davos men".

The phrase "Davos Man" has stuck ever since. This year, 24% of those attending will be women - a pretty poor reflection on the event itself. But the WEF claims that the fact the participation in Davos is overwhelmingly male is not just a problem for it, it's reflective of a problem for world leadership.

And at 24% women attendees its record is better than the total of ministerial positions held worldwide held by women (21%) and a lot more than the proportion of Fortune 100 CEOs, at 6%. In fairness to it, the WEF has committed to doubling the number of women attendees over the next ten years.

It is also making other diversity efforts, like for example holding a teenage "Changemakers" event, to which young people making a positive difference to the world have been invited. Like for example, 13-year-old Naomi Wadler, who campaigns against gun violence in the US.

Business Editor Will Goodbody will be reporting from Davos throughout the week on all RTÉ platforms.