UN officials also submitted ambitious programs in agriculture, forestry, energy, transportation and finance, to fight the greenhouse gasses that are blamed for contributing to climate change.
All this is geared to a conference in Paris next year, at which specific climate change agreements are to be endorsed.
But recent efforts, such as 2009's meeting in Copenhagen, Denmark, have left promises broken and documents unsigned, and raises the question of how much will get done.
"The politics for climate change are so toxic," said Doreen Stabinsky, a professor at the College of the Atlantic and an expert in climate change politics.
"It's hard to step into the international space when many countries, like the U.S., have trouble agreeing at home on what to do," she explained.
Stabinsky said that making a strong commitment to climate change efforts is difficult for many nations because they would have to admit responsibility for climate change, something she said that many countries are loath to do.
There's also being able to agree on what plans should be implemented, said Lynn Wilson, academic chair at Kaplan University and who serves on the climate change delegation for the United Nations.
"We're not talking to the average farmer about what's best for them," she argued. "There's a lot of divisions over climate change and we still have to come to agreement on common goals."
The UN says that climate change increases risk and stress to water, sewer, food supplies, the world's forests, drainage and transportation systems as well as infrastructure.
That's because "these systems are more exposed to the impact of increasingly powerful hurricanes, typhoons and other natural disasters."
But the cost to avoid severe weather events won't be cheap.
There are various estimates but switching from fossil fuels to low-carbon sources of energy will cost $44 trillion between now and 2050, according to a report released last May by the International Energy Agency.
A UN report from the Intergovernmental Panel on Climate Change last April said that efforts to stabilize levels of greenhouse-gas emissions would require investments of about $13 trillion through 2030.
But a study in the Proceedings of the National Academy of Sciences estimates that damages from uncontrolled climate change—an increase of 3.4 degree celsius—could cost $12 trillion or 2.8 percent of global output by 2095.
And delaying action could increase costs by 40 percent every decade, making it ever more costly to do what what's needed.
That's causing some in the financial world to start looking at climate change in a different light, said Paula DiPerna, a special adviser, to the Carbon Disclosure Project, an environmental risk management firm.
"Banks are shying away from companies who don't know how to manage their climate change risk," she said. "And companies are getting better returns on equity over time for investing in green technology."
It's the bottom line that's creating a bigger response to climate change, said Mark Kenber, CEO of The Climate Group, a non-profit environmental organization that works with business and government partners.
"I think the climate change fight will accelerate going forward," he said. "We're seeing countries and companies going beyond just thinking about going green as it's more economical to do so now."
But Kaplan University's Wilson said that it "can't just be all about the money."
Wilson said that calls for increased financial investments in areas such as crop insurance and green energy projects shouldn't come at the expense of strategies like teaching farmers in drought-ridden areas how to plant crops that use less water.
Sincere or not, some countries and businesses are taking bigger steps against climate change.
Forty companies, including Kellogg, L'Oreal and Nestle signed a declaration this week pledging to cut tropical deforestation by half in 2020, and to stop it completely by 2030.
Some 1,000 businesses and investors signaled their support for pricing carbon, to cut greenhouse emissions, in a declaration published by the World Bank Group, It was also signed by 73 countries.
In his speech on Tuesday, President Obama said climate change is not just an "urgent and growing threat" but is "the most important and consequential issue of the 21st Century."
Obama listed steps his administration has taken to stop climate change, such as promoting tougher fuel efficiency standards. He also said he wants to cut American greenhouse emissions.
That's not enough for Kaplan University's Wilson.
"Germany is leading the way on climate change efforts," she said. "The U.S. is still one of the most powerful countries, and if we want to retain that position it's best for us to lead."
Experts say that there is a more awareness of climate change, simply because there are more severe weather events occurring.
Added to that is a bigger grass-roots movement to do something about climate change, said The Climate Group's Kenber.
"The leadership on this is coming from below rather that so much from the top," he said.
What countries do in Paris next year on climate change is still a guessing game, analysts said.
Beyond the speeches and pledges of action this week, there is some hope to go on, said Karl Rábago, executive director of the Pace Energy and Climate Center at Pace Law School.
"From what I saw at the climate march and other events, I believe the needed changes are increasingly seen as unavoidable," Rábago said.
But for College of Atlantic's Stabinsky, it's a struggle to find a bright side.
"I'm generally pessimistic on this," she said. "But on the other hand I have to be optimistic at the same time. We're not going to have a planet if we don't start acting."