Whether the Paris climate agreement motivates humanity to avert a climate apocalypse is a story only the coming years will tell.  I do believe, however, that any encouraging forecasts about the future of life on Earth will depend largely on the individuals and communities who choose a clean energy path.  If such a future comes to pass, I believe the Paris Agreement will have been a catalyzing force.

On December 12, representatives from nearly 200 nations adopted the first international agreement to slow the causes of human-created climate change. Far more ambitious and successful than any previous climate conference, the agreement made at this year’s United Nations Climate Summit incorporated the world: both wealthier northern nations (including the greatest carbon emitters) and southern developing nations, whose carbon footprint is projected to soon surpass that of the north. 

What exactly does the agreement say?
The summit’s 31-page deal outlines a complex plan to cap global greenhouse gas emissions. The plan is to be accomplished primarily by preserving Earth’s intact forests and planting new ones. This is a logical priority: trees are some the world’s most robust absorbers of greenhouse gas. The agreement also addresses the need to focus climate mitigation attention on island nations, where flooding and storms destroy land far more radically than anywhere else. As for a budget, the agreement calls for developed nations to lead the way in financing a clean energy system (primarily wind- and solar-based), which is intended to encourage developing nations away from relying on oil and coal power sources.   

Perhaps most significantly, the agreement outlines a close monitoring of all these plans. Nations will be expected to return with new emission reduction goals every five years beginning in 2023, and will be held accountable for the goals ratified this December.

What precisely will these plans do?
As a whole, the Paris Agreement aims to limit global warming to less than 2 degrees Celsius, or 3.6 degrees Fahrenheit. (Since the Industrial Revolution, Earth has already warmed about 1 degree.) Even more ambitious, the agreement urges nations to cap warming off at 1.5 degrees Celsius. To meet this target, by the end of 2050 industrial greenhouse gas emissions must completely cease. These ambitious goals provide the best odds of averting the temperature at which the massive Greenland and West Antarctic ice sheets will likely melt and radically raise global sea levels. 

What happens now? 
Landmark goals established, “now comes the hard part” as the New York Times stated in its reports on the conference (Dec.14).  Nations must enact their plans and most importantly, stick to them. Hedge fund billionaire-turned-climate activist Tom Steyer, speaking to Times reporter John Schwartz in an interview stated that he believes that the fight to halt greenhouse gas emissions must spread beyond just activist communities to “people doing things in the real world.” In other words, everyone needs to become a climate activist. 

As a 25-year-old native of Portland, Oregon, I see my home community doing exactly that. Portland Mayor Charlie Hales recently passed two resolutions to stop coal industry plans to transform portions of the Northwest U.S.— which would include Portland, where a primary international port is based—into a major fossil fuel export hub. As Jonathan Fink, the interim direction of the Institute for Sustainable Solutions at Portland State told the west coast-based magazine, Pacific Standard, last week (Dec. 10): Portland’s action shows that "cities and regions are where climate leadership is most active today." It’s reassuring that the Paris Agreement has called for the globe to follow this west coast lead to divest from coal- and oil-based energy systems.

The Paris Agreement is a sign that warnings sent to Congress nearly 30 years ago by climate scientists such as James Hansen are trickling into the psyche of global leaders and citizens. In fact, some of the same scientists expressed a lot of optimism for the agreement’s outcome. Leading American climate scientist Christopher B. Field told The Times’s Justin Gilles that “this Paris outcome is going to change the world. We didn’t solve the problem, but we laid the foundation.” (Dec. 12) In the same article Hans Joachim Schellnhuber, the pioneering environmental scientist and climate adviser to Pope Francis, even referred to the agreement as “a turning point in the human enterprise, where the great transformation towards sustainability begins.” 

The world is waking up to the strange reality that human dependence on greenhouse gases has caused seas to rise, severe storms to grow more frequent, agricultural resources to wilt, and our own citizens to flee their homes. For me, the Paris Agreement is a reference point to support conversations about global warming. I can connect the agreement’s emission cap plans to the Pope’s plea for global climate justice, or the refugees who have been forced to leave their land due to changing weather patterns. 

The Paris Climate Agreement means that remarkable environmental success stories like San Diego, California’s unanimous City Council vote to transition to an entirely renewable energy system by 2035 will be taken seriously, and perhaps will provide our global community with some much-needed inspiration. 

Becca Cudmore is a freelance writer and a master's graduate of NYU's science journalism program.