The Paris Agreement is an international agreement on climate change, adopted by 196 parties at the 21st Conference of the Parties (COP21) in Paris in 2015. The agreement aims to limit global warming to well below 2 degrees Celsius above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5 degrees Celsius.

The Paris Agreement went into effect on November 4, 2016, after it was ratified by at least 55 countries representing at least 55% of global greenhouse gas emissions. This milestone was reached on October 5, 2016, when the European Union ratified the agreement, pushing the total number of ratifications over the required threshold.

Since then, the Paris Agreement has been in force for four years, during which time parties to the agreement have been working to implement their commitments. These commitments are referred to as Nationally Determined Contributions (NDCs), which are targets set by individual countries to reduce their greenhouse gas emissions and adapt to the impacts of climate change.

The Paris Agreement also established the Global Stocktake, which will take place every five years starting in 2023. The Global Stocktake will assess the collective progress towards the goals of the Paris Agreement and identify areas where additional action is needed.

In addition to the Global Stocktake, there are several important milestones and events related to the Paris Agreement that will take place in the coming years. In 2020, parties were due to submit updated and enhanced NDCs, but the deadline was pushed to 2021 due to the COVID-19 pandemic. The next COP, COP26, is slated to take place in November 2021 in Glasgow, Scotland, where parties will assess progress towards the goals of the Paris Agreement and set new targets for the next five years.

Overall, the Paris Agreement is a vital tool in the fight against climate change, and its implementation is crucial for the future of our planet. As more and more countries continue to ratify the agreement and work towards their NDCs, we can hope for a sustainable and resilient future for all.