Manya Rathore
Research expert covering India
GHG emissions in the U.S. - statistics & facts
The United States is considered the largest contributor to human-caused climate change, a result of being the biggest emitter in history. It is also the world's second-largest emitter of greenhouse gases on an annual basis, accounting for around 11 percent of global emissions in 2023. Nevertheless, the world’s largest economy has made progress in cutting its emissions, with GHG levels almost 20 percent below what they were in 2005. However, a new president with a “drill baby drill” mantra has raised concerns that the U.S. will retreat entirely from global climate action in the next four years.
The U.S. has made good progress in cutting emissions in recent decades, but a sharp shift in climate policy may impact the country’s net zero goals and setback global efforts in limiting rising temperatures.
U.S. CO₂ emissions trends
CO₂ emissions from energy consumption in the U.S. have decreased by almost 20 percent since peaking in 2005, to 4.8 GtCO₂ in 2023. America’s emission reductions over the past two decades have, in large part, been a result of changes within the country’s power industry. Once the biggest polluter in the U.S., emissions from electricity generation have fallen by more than 35 percent since 2005, following a shift away from coal-fired power in favor of natural gas and renewables. While the power sector has achieved considerable CO₂ emission reductions, those from transportation – the most polluting sector since 2016 – have seen little change in recent years, with the only reductions over the past decade occurring in 2020.Emissions progress at risk
The U.S.’ drive toward a low-carbon economy was set to be driven by the Inflation Reduction Act (IRA) – the largest climate investment in U.S. history, expected to direct billions in federal spending toward clean technologies like electric vehicles, carbon capture, and renewables. In a bid to accelerate decarbonization efforts further, former president Joe Biden set a new Nationally Determined Contribution before leaving office, committing to reducing economy-wide net GHG emissions by 61 to 66 percent below 2005 levels by 2035. However, within hours of reclaiming the presidency, President Trump once again withdrew from the Paris Agreement and pledged to rollback key environmental policies and boost fossil fuel production. Under pre-Trump policies, U.S. emissions were projected to be around 50 percent below 2005 levels by 2035, but if the new Administration were to repeal all components of the IRA and roll back other key climate regulations as announced , U.S. emissions would be only 30 percent below 2005 levels by that same year.The U.S. has made good progress in cutting emissions in recent decades, but a sharp shift in climate policy may impact the country’s net zero goals and setback global efforts in limiting rising temperatures.
