When the world's most powerful political, cultural and business leaders gathered for climate talks, among other global issues, around 1,500 individual private jets flew to and from airfields serving the Swiss ski resort of Davos from Jan 22 to 25.

The World Economic Forum's global risk report, released ahead of the annual meeting, put environmental challenges, including the failure to mitigate climate change, at the top of the list of dangers facing the world economy.

The conclusion was evidenced by two insurance companies' reports.

The economic costs of last year's 394 natural catastrophic events came to $225 billion, with insurance covering $90 billion of the total. It was the fourth-costliest year of insured losses, according to Aon Corp's Weather, Climate & Catastrophe Insight－2018 Insight Report.

The biggest driver of catastrophes in 2018 was the tropical cyclone peril following several significant storms that made landfall, including Hurricanes Michael and Florence (United States); Typhoons Jebi and Trami (Japan); Typhoon Mangkhut (Philippines and China); and Typhoon Rumbia (China).

Aon's report noted that 2017 and 2018 were the costliest back-to-back years on record for both economic losses solely due to weather-related events ($653 billion), and for insured losses covering all perils ($237 billion).

Last year was the fourth-warmest on record since 1880 and the second-warmest (after 2017) without the direct influence of an El Nino event.

German reinsurer Munich Re also released a report that said natural disasters claimed 10,400 lives and caused $160 billion worth of damage to the global economy last year.

Munich Re counted 850 "natural catastrophes" last year, up from 740 in 2017. The average annual cost of disasters over the past 30 years, $140 billion, is still lower than last year's relatively modest total.

The Carbon Disclosure Project, a UK-based nonprofit organization, asked companies to report their environmental impact, including the risks and opportunities they believe climate change presents for their businesses. More than 7,000 companies worldwide filed reports for 2018.

The project found that storms, floods, drought and heat waves worry even the largest companies, while at the same time, Merck, Apple and Home Depot also see new revenue opportunities.

For the vast majority of the companies, the threat is real and serious. Of the 25 companies whose submissions were reviewed by Bloomberg, 21 said they had identified "inherent climate-related risks with the potential to have a substantial financial or strategic impact" on their business.

More frequent hurricanes and wildfires could force AT&T to spend more money on repairing damage to its network, as well as "proactively relocating equipment or additional network hardening". The company noted that disasters cost it $627 million in 2017.

But climate change isn't only a downside for the largest US companies. Many of those that filed reports with CDP said they believe climate change can bolster demand for their products.

More disasters will make iPhones even more vital to people's lives, Apple predicted.

"As people begin to experience severe weather events with greater frequency, we expect an increasing need for confidence and preparedness in the arena of personal safety and the well-being of loved ones,'' the company wrote.

While Google, Facebook and Microsoft have publicly acknowledged the dangers of global warming, they also sponsored LibertyCon, the annual convention of the libertarian group Students for Liberty, which took place in Washington in mid-January. The group promotes denial of climate change.

Google, which was a platinum sponsor, gave $25,000. Facebook and Microsoft each contributed $10,000 as gold sponsors. The donations put the tech companies in the top tier of the event's backers.

Microsoft said in a statement that its commitment to sustainability is not altered or affected by its membership or sponsorship of an organization.

Two independent surveys were conducted late last year on US attitudes on human-driven global warming－one focused on perceptions of risk and the other on possible responses.

The one, conducted by Yale University and George Mason University, found a big rise in the acceptance of scientific evidence of global warming and of humans as the major cause of the change. The percentage of US citizens who say global warming is important to them personally is at a record high, 72 percent, up by 9 percentage points since March, the survey found.

The other poll, by the University of Chicago and the Associated Press, also found increasing acceptance of evidence pointing to human-driven climate change. Among those who said they have become more convinced in the past five years, 76 percent described extreme weather events as the most influential factor shifting their views. The survey also found that 44 percent of respondents would support a carbon tax.

Meanwhile, the United Nations Security Council held an open debate on Friday, discussing the climate's impact on peace and security, and focused on tangible ways to diminish the effects of global warming. Scientists, political representatives and others from around the world also recognized climate change as a "threat multiplier".