A new ranking of cities' plans to combat climate change finds only 43 of nearly 600 cities around the world now earn a top "A" rating.



North America is home to 24 of the cities making an "A" grade.

The new data comes at a time of great global urgency to stem the effects of climate change.

Just 43 of 596 urban areas around the globe earn an "A" rating for measures aimed at cutting emissions and strategies to combat climate change. That's according to new rankings from CDP, a nonprofit that runs a global disclosure system for cities, states, regions, companies and investors. CDP's ratings run from "A" at the top to "D-" at the bottom.

North America was home to 24 top-ranked urban areas worldwide. They include New York, Boston, Toronto, Calgary, Minneapolis and West Palm Beach, a city next door to President Donald Trump's Mar-A-Lago club in Florida. A cluster of nine cities in Northern California near and including San Francisco also made the high end of the list.

CDP's database provides a structure that lets anyone evaluate a city's plans to cut carbon emissions or mitigate climate change -- and how their record stacks up against other municipalities. The group decided to make its city rankings and data public just as the world's population shifts toward urban areas and climate change worsens economic inequality.

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In a recent report, the U.N. predicted almost 70 percent of the global population will live in cities by 2050. In North America, the U.N. said cities are already home to 82 percent of the population. That makes tracking efforts to mitigate emissions and other planet-warming practices vitally important.

Since Mr. Trump announced in 2017 that the U.S. would withdraw from the 2015 Paris Climate agreement, alliances of U.S. cities and states have pledged to stand by the accord's goals to combat the planet's rising temperatures. Under the terms of the Paris agreement, signatories committed to "holding the increase in the global average temperature to well below 2 degrees celsius above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5 degrees celsius above pre-industrial levels."

The Paris deal requires countries to set their own targets for reducing emissions by 2020. But the world isn't yet on the path to reach the agreement's limit. Instead, it's trending toward 3 degrees of warming, according to recent research from Carbon Tracker.In October, a report from the Intergovernmental Panel on Climate Change included measures for urban policymakers that helped spur action.

Some 40 U.S. municipalities submitted data and a questionnaire to the CDP for the first time last year, a "striking" figure, Katie Walsh, who oversees cities, states and regions for the organization in North America, told CBS MoneyWatch. That helped prompt release of the public database and top-ranking cities as examples for the world's urban governments, Walsh said.

"City residents, businesses, leaders -- they're committed to upholding the Paris Agreement and working on climate and reducing pollution," Walsh said. Participants "recognize the benefits from that, despite what the federal government is doing or not doing, [and are] really driving driving that action at the local level," she said.

Similar to elements in CDP's corporate database, the CDP urban database includes a detailed questionnaire and other public disclosures covering climate management, governance, city planning, emissions and even how cities approach areas like social risk and economic benefits. Of global cities earning an "A," 13 aim to be climate-neutral or carbon-neutral by 2050. In North America they include Boston, Indianapolis, Seattle, Washington, D.C., and West Palm Beach, Florida. Those seeking 100 percent renewable energy targets include Minneapolis and San Francisco, according to the CDP.

The data comes at a time of great global urgency. The U.N.'s Panel on Climate Change in a massive report last year detailed how weather, health and ecosystems would be in better shape if the world's leaders could limit future human-caused warming.

Here are the North American cities earning an "A":

Canada

Calgary, Alberta



Toronto

North Vancouver, British Columbia





U.S.