In 2015 in Paris, France, nearly 200 countries signed a landmark agreement aimed at limiting global warming to 1.5 degrees Celsius and avoiding its worst consequences.
Despite some progress in areas such as renewable energy, global temperatures are still rising rapidly.
A recent United Nations report said that global warming is likely to exceed 1.5 degrees Celsius in the next few years, and that "urgent and drastic" action is needed to bring global warming back to less than 1.5 degrees Celsius.
What is the Paris Climate Agreement?
The Paris Agreement is at the heart of the international community's commitment to combat rising global temperatures.
The agreement came into effect on November 4, 2016, with nearly all countries agreeing to reduce emissions of greenhouse gases that contribute to global warming.
However, the United States, the world's second-largest emitter of greenhouse gases, withdrew from the agreement in January 2026 under President Donald Trump.
The United States also withdrew during Trump's first term as president, but rejoined in 2021 after his successor, President Joe Biden, took office.
Among United Nations member states, only Iran, Libya and Yemen have not joined the Paris Agreement.
What does the Paris Agreement stipulate?
The Paris Agreement sets out a series of commitments:
"Efforts" to limit global temperature rise to 1.5 degrees Celsius and to keep the increase to "well below" 2.0 degrees Celsius above pre-industrial levels - generally thought to refer to the late 19th century;
Achieve a balance between the greenhouse gases humans emit into the atmosphere and the gases we actively remove in the second half of this century, so-called net zero;
Each country should set its own emissions reduction targets, with a review every five years to improve them;
Richer countries should provide finance (i.e. climate finance) to help poorer countries adapt to climate change and shift to renewable energy.
It is generally believed that the 1.5 degrees Celsius target refers to the average level over 20 years, rather than a specific year.
Therefore, although temperatures in 2024 will be more than 1.5 degrees Celsius higher than pre-industrial times, this does not mean that the Paris Agreement threshold has been breached.
Why is it so important to limit global warming to 1.5 degrees Celsius?
Climate scientists say that every 0.1 degree Celsius of temperature increase puts the planet at greater risk, such as longer heatwaves, more intense storms and wildfires.
But U.N. scientists say there is overwhelming scientific evidence that warming of 2 degrees Celsius or more will have far greater impacts than those of 1.5 degrees Celsius.
These include:
More people exposed to extreme heat
Melting glaciers and ice caps cause sea levels to rise
The increase in extreme weather has led to increased food security risks in some areas
Certain climate-sensitive diseases, such as dengue fever, are more likely to spread
More species are threatened with extinction
Almost all coral reefs disappeared
If so-called "tipping points" are crossed, some changes may become irreversible.
Exactly where these tipping points lie is unclear, but once they are crossed, changes are likely to be accelerated and irreversible.
These could include the collapse of the Greenland ice sheet, the Atlantic Ocean Current or further loss of the Amazon rainforest.
What can the Paris Agreement bring to poorer countries?
The Paris Agreement reiterates a 2009 pledge that richer countries should provide $100 billion (667.4 billion yuan; NT$3.28 trillion) per year by 2020 to help developing countries cope with the effects of climate change and build greener economies.
Although only $83.3 billion was raised in 2020, OECD data shows that the target was reached in each of the three years after 2022.
In recent years, nearly two-thirds of funding has gone to efforts to limit global warming, while about a quarter has been used to help countries adapt to climate change.
In 2023, for the first time, countries reached a consensus to establish a fund specifically to deal with loss and damage. The funding will be used to help countries recover from the impacts of climate change.
Nepal became the first country to be approved to receive funds from the fund after flash floods killed more than 1,400 people in August 2026.
At the 29th Conference of the Parties to the United Nations Framework Convention on Climate Change (COP29) in 2024, wealthier countries pledged to provide developing countries with US$300 billion (2.22 trillion yuan; NT$9.84 trillion) per year by 2035. Developing countries, which had hoped for more aid, criticized the amount as "paltry".
What has happened since the Paris Agreement was signed?
World leaders come together every year to discuss their climate commitments at an international summit called the Conference of the Parties (COP).
Since 2015, successive COPs have tracked how countries are implementing the commitments they made in Paris.
At COP28 in 2023, countries agreed for the first time to "contribute" to the "transition away from fossil fuels", although countries were not asked to take any specific actions.
Countries have also agreed to triple the global installation capacity of renewable energy sources such as wind and solar by 2030.
But the final COP30 agreement in 2025 does not directly mention fossil fuels. Instead, conference host Brazil has released a voluntary roadmap for phasing out fossil fuels, which will be discussed at the 31st Conference of the Parties (COP31).
From November 9 to 20, 2026, COP31 will be held in Antalya, Turkey (COP31), and Australia is a co-host.
A "coalition of the willing" of 57 countries has also organized its own meeting, separate from the COP process, to discuss the gradual transition away from fossil fuels. The first meeting will be held in Santa Marta, Colombia, in April 2026, and another meeting is scheduled for July 2027 in Tuvalu.
Can the world achieve the goal of 1.5 degrees Celsius warming as planned?
The long-term goal of limiting global warming to 1.5 degrees Celsius has yet to be exceeded.
But the latest United Nations Emissions Gap Report says that limit is likely to be exceeded in the coming years after "decades of inadequate climate action".
The report said that even under the "lowest possible" scenario, global warming will still reach 1.7 to 1.8 degrees Celsius by the middle of this century.
