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.
It is virtually certain our world will continue to warm over this century and beyond. The exact amount of warming that will occur in the coming century depends largely on the energy choices that we make now and in the next few decades.
From the African savanna to North America’s boreal forests, NOAA’s CarbonTracker tool provides insight into what natural and human processes affect the uptake, release, and transport of carbon dioxide in Earth’s lower atmosphere.
Meeting internationally discussed targets for limiting atmospheric greenhouse gas concentrations and associated increases in global average temperatures will require a major departure from business as usual in how the world uses and produces energy. This report from the America’s Climate Choices suite of studies recommends that a U.S. policy goal be stated in terms of a budget for cumulative greenhouse gas emissions over the period 2012 to 2050.