[Vision2020] NOAA: Carbon Dioxide, Methane Rise Sharply in 2007
starbliss at gmail.com
Wed Apr 23 21:48:13 PDT 2008
Carbon Dioxide, Methane Rise Sharply in 2007
April 23, 2008
Last year alone global levels of atmospheric carbon dioxide, the primary
driver of global climate change, increased by 0.6 percent, or 19 billion
tons. Additionally methane rose by 27 million tons after nearly a decade
with little or no increase. NOAA scientists released these and other
preliminary findings today as part of an annual update to the agency's
greenhouse gas index <http://www.esrl.noaa.gov/gmd/aggi>, which tracks data
from 60 sites around the world.
The burning of coal, oil, and gas, known as fossil fuels, is the primary
source of increasing carbon dioxide emissions. Earth's oceans, vegetation,
and soils soak up half of these emissions. The rest stays in the air for
centuries or longer. Twenty percent of the 2007 fossil fuel emissions of
carbon dioxide are expected to remain in the atmosphere for thousands of
years, according to the latest scientific assessment by the International
Panel on Climate Change.
Viewed another way, last year's carbon dioxide increase means 2.4 molecules
of the gas were added to every million molecules of air, boosting the global
concentration to nearly 385 parts per million (ppm). Pre-industrial carbon
dioxide levels hovered around 280 ppm until 1850. Human activities pushed
those levels up to 380 ppm by early 2006.
The rate of increase in carbon dioxide concentrations accelerated over
recent decades along with fossil fuel emissions. Since 2000, annual
increases of two ppm or more have been common, compared with 1.5 ppm per
year in the 1980s and less than one ppm per year during the 1960s.
Methane levels rose last year for the first time since 1998. Methane is 25
times more potent as a greenhouse gas than carbon dioxide, but there's far
less of it in the atmosphere—about 1,800 parts per billion. When related
climate affects are taken into account, methane's overall climate impact is
nearly half that of carbon dioxide.
Rapidly growing industrialization in Asia and rising wetland emissions in
the Arctic and tropics are the most likely causes of the recent methane
increase, said scientist Ed Dlugokencky from NOAA's Earth System Research
"We're on the lookout for the first sign of a methane release from thawing
Arctic permafrost," said Dlugokencky. "It's too soon to tell whether last
year's spike in emissions includes the start of such a trend."
Permafrost, or permanently frozen ground, contains vast stores of carbon.
Scientists are concerned that as the Arctic continues to warm and permafrost
thaws, carbon could seep into the atmosphere in the form of methane,
possibly fueling a cycle of carbon release and temperature rise.
NOAA is dedicated to enhancing economic security and national safety through
the prediction and research of weather and climate-related events and
information service delivery for transportation, and by providing
environmental stewardship of our nation's coastal and marine resources.
Through the emerging Global Earth Observation System of Systems
NOAA is working with its federal partners, more than 70 countries and the
European Commission to develop a global monitoring network that is as
integrated as the planet it observes, predicts and protects.
Vision2020 Post: Ted Moffett
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the Vision2020