As of 2013, the warming effect of long-lived greenhouse gases in Earth's atmosphere has increased by approximately 34% since 1990.

NOAA’s updated Annual Greenhouse Gas Index (AGGI), which measures the direct climate influence of many greenhouse gases such as carbon dioxide and methane, shows a continued steady upward trend...

Carbon dioxide remains the undisputed king of recent climate change, but other greenhouse gases measurably contribute to the problem. A new study, conducted by NOAA scientists and published online...