Column: Who will be next to lead the UN?

As any New Yorker knows from the traffic disruptions, last week marked the opening of the 71st General Assembly of the United Nations. At the end of the year, Secretary-General Ban Ki-moon will step down after a decade of service, making this the last time the former South Korean foreign minister presides over the event.

It’s also the last General Assembly for President Barack Obama. In his speech Tuesday, Obama made an impassioned defense of liberal democracy and globalization, while acknowledging that countries need to combat rising inequality. In addition to this broad ideological vision, he also discussed a number of specific challenges the global community must address together in the coming years, including climate change, human displacement and pandemics.

WATCH: Obama sounds optimistic note in final U.N. speech

The secretary-general is also stressing these mounting problems. One of Ban’s top priorities for his final meeting is climate change. During the Assembly, he has been trying to get countries to accept the Paris climate accords as legally binding. In particular, he wants the U.S. locked in before the presidential election, which Donald Trump, a global warming skeptic, could win. To ratify the agreement, Ban needs “at least 55 countries representing 55 percent of climate-change emissions,” according to The New York Times

The U.S. and China have signed on, but India, the third biggest emitter, has been reluctant. Ban garnered the support of 31 more countries, bringing the total to 60 and closer to the needed world emissions threshold. If it does go into force, the Paris accord would create a framework for limiting emissions and setting temperature goals as well as providing aid to less developed countries.

READ MORE: 31 more countries ratify Paris climate pact, including Argentina and Brazil

Another major concern hanging over this year’s General Assembly is the migrant crisis. The U.N. estimates that today there are 65 million people displaced worldwide, more than at any time since World War II. It is appropriate that migration and climate change are sharing the spotlight this year, since global warming is an underappreciated factor driving the rise of displacement.

During a Monday session devoted to refugee and migrant issues, world leaders adopted the New York Declaration, a resolution to be more proactive in helping refugees. Prior to the meeting, Secretary of State John Kerry announced that America would voluntarily accept 30 percent more refugees in 2017 than it did in 2016. And the private sector pitched in as well, led by a $500 million commitment from billionaire George Soros to invest in helping refugees and migrants. Fifty-one other companies, including Airbnb and Western Union, said they would help improve access to jobs and education for refugees across 20 countries.

A third headline issue at the General Assembly is antimicrobial resistance. The rampant use of antibiotics in medicine and agriculture has enabled the rise of drug-resistant bacteria known colloquially as superbugs. The phenomenon already claims 700,000 lives each year. If left unaddressed, the cumulative global cost of superbugs could reach $100 trillion.

The U.N. recognizes the magnitude of the problem and is trying to raise its profile. According to Scientific American, “this month’s high-level UN meeting represents only the fourth time in the international body’s history that its General Assembly…has held a meeting to tackle a health topic.” Officials do not expect anything legally binding to pass, but member states could formally declare their commitment to addressing the issue as a step toward more formal measures.

READ MORE: UN leaders to put superbugs on world stage

Reflecting on his decade of leadership, Ban is proud of the progress he helped drive on issues like these. But his tenure has not been without its frustrations. For example, the secretary-general has pointed to leaders threatening to cut off funding for U.N. programs if he did not remove Israeli and Saudi Arabian forces from a list of armies that kill and maim children. In both cases, he relented.

Ban defends his actions as partly due to inherent limitations in the way the U.N. makes decision. As he recently stressed to the Associated Press, because the U.N. is a consensus-driven organization, individual countries have outsized power to blackball issues they don’t like. This constrains what the U.N. can accomplish. Unsurprisingly, the secretary-general recently hinted he would like to see the decision structure of the U.N. altered to increase its effectiveness.

Institutional shortcomings aside, Ban himself is not without critics. The Economist called him “painfully ineloquent, addicted to protocol and lacking in spontaneity and depth,” adding that he is “widely regarded as a failure in both administration and governance.” Critics say he has at times failed to stand up for human rights.

He’s also been called a “powerless observer” in the face of tragedies like the 2009 civil war in Sri Lanka, and more recently in Syria. And it took Ban six years to publicly acknowledge the role his organization played in bringing on the 2010 cholera outbreak in Haiti that claimed 9,000 lives. So while Ban believes the institution of the U.N. requires reform, others see a more assertive leader as an equally urgent need.

So who might be the next leader of the U.N.? Ban’s opinion is that it should be a woman. Unfortunately, countries have to date failed to rally around a female candidate, despite a record number vying for the post. I strongly agree with the need for gender diversity, particularly in high profile positions such as this. An organization representing humanity should have a leadership that is representative of humankind.