A lot can change in nine months.

In January, when the World Economic Forum released its list of the biggest threats to world stability, the group seemed to cover a pretty wide spectrum. But the ensuing months have seen several new crises emerge.

Some are offshoots of broad categories the WEF warned about. Some are things they didn't imagine. But each have become significant enough to warrant concern. No wonder some are major topics being widely discussed at the United Nations—and even by Pope Francis. Today, at the annual Clinton Global Initiative in New York City, CEOs and other leading thinkers will also ponder on the dire consequences of these risks.

—By Chris Morris, special to CNBC.com
Posted 26 September 2015

While refugees have been fleeing the Middle East, Africa and Asia for a while, the April sinking of five boats, drowning more than 1,200 people, put it on people's radars. And the horrific image of Aylan Kurdi, a 3-year-old who drowned in the waters off Greece, made it front-page news. Hundreds of thousands of people, fleeing war-torn regions like Syria and South Sudan, are seeking asylum, forcing countries to reestablish border controls and some, like Hungary, to close down their borders. Germany alone said it expects 1 million migrants to arrive this year.

What's the threat? Beyond the obvious risk to the refugees themselves, an uncontrolled influx of people could overwhelm social welfare systems and cause an economic crisis. The influx is also creating significant tension among the European Union as countries disagree about their humanitarian responsibilities. Member states are fighting among themselves. Germany is urging members to welcome the refugees. But countries like Hungary, the Czech Republic and Slovakia are reticent to do so. That in turn has prompted Austria to suggest putting financial pressure on countries that reject quotas. And some political analysts say this could be an issue that causes governments to fall.

The Islamic State militant group was one of the things the WEF warned about earlier this year, citing the threat of both "state collapse" and "failure of national governance." But the group's threat level has risen considerably this year. In February, militants captured part of the Libyan countryside near Sabha. In March, Boko Haram pledged allegiance to the group, expanding its presence to Nigeria, Chad and other parts of Africa. And ISIS currently holds roughly one-third of the Syrian territory and sizable areas in Iraq.

What's the threat? The threat of ISIS causing a state collapse remains very real, despite heavy casualties to the group by a U.S.-led joint task force (which says it's killing about 1,000 ISIS fighters per month). And recent audio messages from al Qaeda leader Ayman al-Zawahiri seem to indicate the terror organization is open to settling its differences with ISIS and has called on its affiliate in Syria, Jabhat al-Nusra, to cooperate with ISIS in the battle for that country.

In a two-day period in late July, China's stock market stumbled badly, with the Shanghai Composite falling nearly 15 percent. Between mid-June and early August, it fell twice that much, wiping out $4 trillion in market value. Foreign investors are avoiding the country. And on Aug. 24, "Black Monday," the markets lost another 8.49 percent of its value, triggering selloffs around the globe. In the U.S., the Dow started the day tumbling more than 1,000 points before regaining some ground and closing down at 588 points.

What's the threat? China is the world's second-largest economy. The ripple effect from an economic crisis there could affect businesses in the U.S. and other countries. The country's growth in recent years lifted economies that were trying to shake off things like the downgrade of America's credit rating and Greece's economic troubles. And the free fall of stocks has raised questions about whether China will continue with its free-market reforms. Should that happen, it could slow world trade.

Created when the equatorial waters in the Pacific Ocean warm significantly, El Niño can have a big impact on global weather patterns. And forecasters say this one could be one of the strongest ever.

What's the threat? It could be considerable or negligible, depending on where you live. For instance, people along the East Coast of the U.S. can thank it for the relatively weak Atlantic hurricane season. And part of the West Coast could see a lessening drought, with mudslides and intense storms taking its place. Britain, meanwhile, is bracing for its coldest winter in 50 years. South Africa, Indonesia and Australia are all preparing for droughts. And it's even being blamed for a surge in snakebites.

The landmark agreement between Iran, the U.S. and other world powers this summer is aimed at curbing the nuclear program in the country. The deal puts very strict limitations on Iran's nuclear programs for the next 10 years. Following that, the restraints will ease over a five-year period. President Obama has praised the deal, saying he is "confident that this deal will meet the national security interests of the United States and our allies." Public support for the agreement has been eroding, though, since it was announced.

What's the threat? Opponents argue the $150 billion in sanctions relief that Iran will receive under the deal can be used to finance terror operations. And they're skeptical that the nuclear inspections requirement is sufficient. Iran will be allowed to continue enrichment, even though it must give up its centrifuges (which enrich uranium) and rebuild its heavy-water reactor. Opponents, such as Republican Speaker of the House John Boehner, say the deal could "fuel a nuclear arms race around the world."

Talks aimed at ending North Korea's nuclear program have been stalled since 2009, and earlier this year, satellite images suggested the country has restarted its nuclear program, which has been shuttered since 2007. North Korean officials this month said the company was prepared to use those weapons against the U.S. if it continues its "reckless hostile policy" toward leader Kim Jong-un. The country has also announced it is planning more satellite launches, which are viewed as a way of testing ballistic missiles.

What's the threat? The state of North Korea's nuclear program is fairly unclear, and while most officials do not believe the nation has the ability to target the U.S. mainland, it can still reach the nation's allies and outlying states, like Alaska and Hawaii. And officials in Washington have called North Korea's nuclear weapons program a threat to world security. The renewed threats come weeks after North Korean and South Korean troops exchanged artillery fire across the border. The skirmishes did not result in any casualties.