World leaders call it a historic climate pact. Others say the agreement does not go far enough and might remain an empty shell. DW takes a closer look.
The actual treaty is made up of 11 pages and 29 articles. They set out in black and white how 195 nations plan to tackle climate change in the future.
French Foreign Minister Laurent Fabius called it "ambitious and balanced." adding that it would mark a "historic turning point." United States Secretary of State John Kerry said that the pact would "prevent the worst, most devastating consequences of climate change from ever happening."
Nongovernmental organizations were less satisfied with the agreement, and warn that "the treaty might become an empty shell." It defines the goal, but not the pathway to reach that goal, they say.
"It won't contribute to stopping climate change at all," Andreas Link of BUND Jugend, a German conservationist youth group, told DW. He added that only civil society itself was able to prevent climate change.
Kumi Naidoo, International Executive Director of Greenpeace, was more optimistic in a DW interview: "It's certainly not what we dreamt of - but what is significant is that every country in the world now agrees that we are in a climate crisis, that we have to act and that we have to act with urgency."
Limiting temperature rise
That 195 nations were able to work out such a document together is indeed a big achievement. For the first time, there is a treaty that obliges all nations of the world to protect the climate.
In article 2, the parties agree to "limit the increase in the global average temperature to well below 2 degrees Celsius above preindustrial levels and to pursue efforts to limit the temperature increase to degrees Celsius above preindustrial levels." We have already reached a rise of nearly a degree.
Article 4 reads that parties aim "to reach global peaking of greenhouse gas emissions as soon as possible."
An increase of "only" 1.5 degree Celsius, though, might already be too much, scientists say. Ice sheets are already starting to melt, and extreme weather events have increased around the world. And warming to date might cause loss of the planet's coral reefs.
However, if the climate deal succeeds in reducing emissions, it would at least prevent the worst, slowing down some of the most severe consequences of an overheated planet.
The new agreement starts only at the end of 2020 when the Kyoto protocol ends. But experts warn that action must be taken as soon as possible.
They stress that there is a time lapse between the emission of a certain amount of greenhouse gases and temperature rise. So even after we stop our emissions completely, the temperature will still increase. To keep to an increase of 1.5 degrees Celsius, we would have to reduce our emissions to zero now.
The treaty aims at "a balance between anthropogenic emissions by sources and removals by sinks of greenhouse gases in the second half of this century."
Tougher formulations such as "decarbonization" or "zero emissions" didn't find their way into the Paris Agreement.
In other words: Nations will still be allowed to burn coal and oil and emit greenhouse gases from such activities, they would just have to neutralize these emissions somehow - for example by planting new forests, or with as yet experimental technical means like carbon capture and storage.
Achieving a balance in emissions and removal has to happen "in the efforts to eradicate poverty," the treaty reads.
India is said to have insisted on this text passage. The country doesn't want to give up on cheap electricity from coal - it says that it is needed to free hundred of millions of Indians from poverty.
Loss and damage
Yes, climate change does cause loss and damage, article 8 reads - and it is important to avert and minimize these.
Developed countries thus acknowledge that climate change - caused by greenhouse gases, which up to now have been emitted mainly by developed nations - may ruin cities and homes, and destroy lives due to extreme weather events and other developments. This acknowledgement alone is a small victory for developing nations.
"Action and support" are needed, the agreement says, which include early warning systems and risk-insurance facilities. A climate change-related insurance facility supported by developed countries might be a solution.
Not all binding
The Paris Agreement includes a promise by rich countries to channel at least $100 billion annually from 2020 to help climate-vulnerable countries.
This, however, is not part of the legally binding treaty portion. It was shifted into the "decisions," the second part of the agreement, which is without obligation.
Media and observers say that this was a trick to bypass US Congress, which would have to approve the treaty if the $100-billion payout were to have been legally binding.
The same goes for the actual greenhouse gas emissions that a country is allowed to make - the treaty holds no figures for these amounts. According to experts, this is also a way to circumvent US Congress.
Instead, every five years, each country has to report its individual climate goals. Transparency rules on reporting, however, are binding - an important point that can help make sure nations fulfill their emission reduction obligations.
US on the brink?
Critics say that the United States, the world's biggest economy, might back away from the targets set in the Paris climate agreement if the Republican Party wins next year's presidential election in the US.
The Republican majority in Congress has repeatedly and clearly shown what it thinks of protecting the climate: nothing at all.
Republican US Senator Mitch McConnell told the media on Sunday the agreement would be subject "to being shredded" after the election. The politician from Kentucky, a coal-producing state, said the agreement would hurt US employment and raise utility rates.
Environmentalists, though, remain surprisingly calm in saying that it won't be easy - even for a future US president - to cancel international obligations pegged to the Paris Agreement.
Economy and businesses
The Paris Agreement is very good news for companies involved in renewable energies. They might be able to expand their markets.
Goldman Sachs' analysts said the Paris Agreement would boost the world's low carbon economy, which it estimated as a fast-growing $600-billion-plus market.
European renewable energy stocks already rallied on Monday, two days after the climate deal was agreed upon. Norway's REC Silicon, which makes the key raw material for solar panels, surged 10 percent. Shares in wind turbine makers, constructors of solar power generators and of biofuel technology firms also climbed.
The fossil-fuel industry, though, will be less happy about the climate deal.
Where to go from here
Heads of state will sign the treaty on April 22, 2016, in New York. At least 55 nations that are responsible for at least 55 percent of the global greenhouse gas emissions have to sign to make the document legally binding. But since the agreement was painstakingly hammered out in a consensus process, it is expected that countries that participated in this process will sign.