NOAA indicated in a release that carbon dioxide pumped into the atmosphere by fossil fuel burning and other human activities is the most significant greenhouse gas (GHG) contributing to climate change. Its concentration has increased every year since scientists started making measurements on the slopes of the Mauna Loa volcano more than five decades ago. The rate of increase has accelerated since the measurements started, from about 0.7 ppm per year in the late 1950s to 2.1 ppm per year during the last 10 years. NOAA senior scientist Pieter Tans, with the Global Monitoring Division of NOAA's Earth System Research Laboratory in Boulder, CO said, "That increase is not a surprise to scientists. The evidence is conclusive that the strong growth of global CO2 emissions from the burning of coal, oil, and natural gas is driving the acceleration."
NOAA indicated that before the Industrial Revolution in the 19th century, global average CO2 was about 280 ppm. During the last 800,000 years, CO2 fluctuated between about 180 ppm during ice ages and 280 ppm during interglacial warm periods. Today's rate of increase is more than 100 times faster than the increase that occurred when the last ice age ended.
Researcher Charles David Keeling of the Scripps Institution of Oceanography, UC San Diego, began measuring carbon dioxide at Mauna Loa in 1958, initiating now what is known as the "Keeling Curve." His son, Ralph Keeling, also a geochemist at Scripps, has continued the Scripps measurement record since his father's death in 2005. Ralph Keeling said, "There's no stopping CO2 from reaching 400 ppm. That's now a done deal. But what happens from here on still matters to climate, and it's still under our control. It mainly comes down to how much we continue to rely on fossil fuels for energy." NOAA scientists with the Global Monitoring Division have made around-the-clock measurements there since 1974. Having two programs independently measure the greenhouse gas provides confidence that the measurements are correct.
Moreover, similar increases of CO2 are seen all over the world by many international scientists. NOAA, for example, which runs a global, cooperative air sampling network, reported last year that all Arctic sites in its network reached 400 ppm for the first time. These high values were a prelude to what is now being observed at Mauna Loa, a site in the subtropics, this year. Sites in the Southern Hemisphere will follow during the next few years. The increase in the Northern Hemisphere is always a little ahead of the Southern Hemisphere because most of the emissions driving the CO2 increase take place in the north. Once emitted, CO2 added to the atmosphere and oceans remains for thousands of years. Thus, climate changes forced by CO2 depend primarily on cumulative emissions, making it progressively more and more difficult to avoid further substantial climate change.
The Executive Secretary of the UN Framework Convention on Climate Change (UNFCCC) Christiana Figueres called for a greatly stepped-up response to climate change by all parts of society. She said, "With 400 ppm CO2 in the atmosphere, we have crossed an historic threshold and entered a new danger zone. The world must wake up and take note of what this means for human security, human welfare and economic development. In the face of clear and present danger, we need a policy response which truly rises to the challenge. We still have a chance to stave off the worst effects of climate change, but this will require a greatly stepped-up response across all three central pillars of action: action by the international community, by government at all levels, and by business and finance." UNFCCC indicated that governments will be meeting June 3 - 14, in Bonn for the next round of climate change talks under the umbrella of the UNFCCC. A central focus of the talks will be negotiations to build a new global climate agreement and to drive greater immediate climate action.
"The people with their foot on the gas pedal are the dirty fuel and logging industries, with the coal industry alone responsible for two thirds of recent frantic emission growth. And they have no intention of slowing down. Massive coal expansions are planned in Australia, China and the U.S., that would lock in increasing emissions for decades. Stopping or scaling back these projects is absolutely necessary to keep global warming from accelerating further out of control."
Access a release from NOAA with links to monitoring data, the Maua Loa Observatory, animation and images (click here). Access a release from UNFCCC (click here). Access the 400.350.org (click here). Access a release from Greenpeace (click here). [#Climate]