Scientists are observing changes in the Earth’s climate in every region and across the whole climate system, according to the latest Intergovernmental Panel on Climate Change Report. Many of the changes observed in the climate are unprecedented in thousands, if not hundreds of thousands of years, and some of the changes already set in motion — such as continued sea level rise — are irreversible over hundreds to thousands of years, according to the IPCC.
However, strong and sustained reductions in emissions of carbon dioxide and other greenhouse gases would limit climate change. While benefits for air quality would come quickly,
