Some of the chemicals that replaced ozone-harming CFCs are long-lived greenhouse gases. At NOAA's lab in Boulder, Colorado, chemist Steve Montzka leads the effort to monitor the concentration of CFC-substitutes and their potential impact on global warming.
For 800,000 years before the twentieth century, carbon dioxide levels in Earth’s atmosphere never exceeded 300 parts per million. In March 2015, the monthly average went above 400 ppm for the first time.
Charles Keeling's measurements of carbon dioxide from the summit of Mauna Loa have become a landmark for mankind’s impact on the Earth. In this video, NOAA scientists talk about the history of the observations that allow us to connect Earth's warming climate to the greenhouse gases from burning fossil fuels.
Restoring a healthy balance between sea otters and their sea urchin prey comes with a modest but meaningful bonus: halting the overgrazing of kelp forests and increasing their ability to remove excess carbon dioxide from the atmosphere.
The annual average concentration of carbon dioxide (CO2) in the atmosphere stood at 395.3 parts per million (ppm) in 2013—a 27 percent increase compared to conditions before the Industrial Revolution. On May 9, 2013, the daily average concentration of CO2 surpassed 400 ppm for the first time at the Mauna Loa Observatory in Hawaii.
Since 2004, researchers in NOAA’s Global Monitoring Division have released the Annual Greenhouse Gas Index: a single value that compares the total warming effect of each year's concentrations of heat-trapping gases to 1990 levels.
CarbonTracker is a tool for modelling sources and sinks of carbon dioxide. Users can download the code, carbon dioxide data, and the tool's carbon flux estimates to conduct their own analyses or to help improve the system.