Carbon Dioxide Rise in 2012 Second Highest in Modern Record

By Tom Yulsman | March 6, 2013 9:07 pm

The annual mean growth rate in atmospheric carbon dioxide from 1959 through 2012, as measured atop Mauna Loa in Hawaii. (Graph:

The graph above tells the tale: Last year, concentrations of heat-trapping carbon dioxide in the atmosphere jumped by the second highest amount since modern monitoring began in 1959.

According to Pieter Tans, a National Oceanic and Atmospheric Administration scientist who leads the effort to track CO2 levels, the rise was driven mostly by increasing emissions of the greenhouse gas, thanks in large measure to more coal-burning power plants in the developing world.

As reported by the Associated Press, Tans said the new findings suggest that the prospects for limiting average global warming to less than 2 degrees C over preindustrial levels are fading. Beyond that threshold, the odds of dangerous climatic impacts rise significantly, in the view of many scientists.

The graph below charts the rise in CO2 in parts per million, as measured on Hawaii’s Mauna Loa, since 2009:


The dashed red line represents the monthly mean values. The oscillation results from the growth cycle of plants in the Northern Hemisphere (which has more landmass than the Southern Hemisphere, and thus more vegetation).  The black line charts the rise in CO2 with the seasonal cycle removed.



ImaGeo is a visual blog focusing on the intersection of imagery, imagination and Earth. It focuses on spectacular visuals related to the science of our planet, with an emphasis (although not an exclusive one) on the unfolding Anthropocene Epoch.

About Tom Yulsman

Tom Yulsman is Director of the Center for Environmental Journalism and a Professor of Journalism at the University of Colorado, Boulder. He also continues to work as a science and environmental journalist with more than 30 years of experience producing content for major publications. His work has appeared in the New York Times, Washington Post, Audubon, Climate Central, Columbia Journalism Review, Discover, Nieman Reports, and many other publications. He has held a variety of editorial positions over the years, including a stint as editor-in-chief of Earth magazine. Yulsman has written one book: Origins: the Quest for Our Cosmic Roots, published by the Institute of Physics in 2003.


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