As Michael Bloomberg decides to whether to run for president, he continues to spread a message on global warming.

The former Mayor has a simple request: Keep pushing for change.

“The public is upset with all of those who say there's nothing going on, and then there's a flood where there wasn't water before, and then there's a drought where there used to be lots of water, and the ski resort that they want to go to doesn't have any snow.”

Bloomberg said the private sector and cities across the United States have made significant progress,by closing 200 out of the 500 coal-fired power plants in the country.

He also praised the Chinese government for its recent initiatives on climate change, including closing four power plants in Beijing.

Also addressed investors, Christiana Figueres, of the U.N. Framework Convention on Climate Change, said by 2030, the chapter on high carbon fossil fuels must be closed.

“There is a huge impact if we put money into the wrong fuels, into the wrong energy systems.”

The summit's organizer, Ceres-a nonprofit sustainability advocacy organization—hopes to accomplish what it calls the “Clean Trillion” challenge:a renewable energy investment goal of $44 trillion, or $1 trillion per year, by the world's leading businesses and investors.

Former U.S. Vice President Al Gore, with champion the cause of climate change action,has argued that the cost of renewable energy will sharply decline in coming years, providing nations with a ability to do more to curb global missions.

The investment community, Gore says, has an important role in leading that effort.