The Paris Agreement, a global plan to combat climate change, was adopted in December 2015. The United States was one of the signatories to the agreement and committed to reducing its greenhouse gas emissions by 26-28% below 2005 levels by 2025. This commitment was known as the Nationally Determined Contribution (NDC) and was a key part of the agreement.

However, in 2017, the Trump administration announced that the United States would withdraw from the Paris Agreement, citing concerns about the impact on the U.S. economy. The withdrawal was completed in November 2020, but President Biden immediately began the process of rejoining the agreement upon taking office in January 2021.

The Biden administration has also announced a new NDC for the United States, which aims to reduce greenhouse gas emissions by 50-52% below 2005 levels by 2030. This is a significant increase in ambition compared to the previous NDC and reflects the urgency of the climate crisis.

The new NDC includes a range of measures to achieve the emissions reduction target, including:

- Increasing the use of renewable energy and phasing out coal power

- Encouraging the adoption of electric vehicles and investing in charging infrastructure

- Improving energy efficiency in buildings and appliances

- Supporting the development and deployment of new technologies, such as carbon capture and storage

The Biden administration has also announced plans to host a Leaders Summit on Climate in April 2021, where world leaders will come together to discuss further action on climate change.

The Paris Agreement and the NDCs are important tools in the global effort to combat climate change. While the United States has a significant role to play in this effort, it is also important for all countries to work together to achieve the shared goal of limiting global warming to 1.5 degrees Celsius above pre-industrial levels. By committing to ambitious targets and taking bold action, we can build a more sustainable and resilient future for all.