Monday, September 6

Coal Sky

Forgotten about global warming? Here is one to ponder: 29 billion tons of CO2 emitted into our atmosphere in 2007. Photo from Bullfrog Builders; sobering following our summer travels through some of the most scenic land in America.

Since the Industrial Revolution concentrations of most greenhouse gasses have increased rapidly. In 2007, the Intergovernmental Panel on Climate Changed found the three primary GHGs - carbon dioxide, methane, and nitrous oxide - had risen 35%, 148% and 18%, respectively, when comp'd to pre-industrial levels. These levels are significantly higher than any time during the last 650,000 years based on data from Antarctic ice cores (Siegenthaler, Urs; et al). Moreover, recent data suggests key GHGs are increasing at an accelerated rate - in the 1960s, the average GHG concentration was 37% of what it was from 2000 to 2007 (Dr. Peter Tans, "Annual C02 Mole Fraction Increase from 1959-2007").

CO2 is the leading GHG and a primary cause of global warming, whose rise in atmospheric levels directly attributable to human activities. Fossil fuel combustion alone is responsible for roughly 75% of emissions, which have grown 145-fold since 1850. The IEA estimates atmospheric CO2 will grow by another 54% by 2030 in absence of regulation. At their current trajectory, rising GHG concentrations threaten to push temperatures upward by as much as 11-degrees Fahrenheit (Intergovernmental Panel on Climate Change, 2007)

Coal, not surprisingly, is the villain accounting for 26% of the world's primary energy supply and 42% of the CO2 emissions. More specifically, coal in power generation produces aprox. 1,100 grams of CO2/kWh followed by oil (900) and natural gas (650). Wind power, geothermal and hydroelectricity are less than 50. Coal is by far the most abundant and most accessible carbon on Earth with estimates that the existing supply may last 250 years (McKinsey & Co). It is also the cheapest energy source at nearly a quarter of solar and 60% nuclear (Source: EIA, 2010; MIT). Coal will be with us for a long time - we have made tremendous investment in our coal-fired infrastructure to enable global electricity demand, which is set to grow 76% from 2007 to 202 (IEA World Energy Outlook, 2009)

I suppose if there is any good news, governments are reacting despite Copenhagen's failure: 72 countries have legislated or continue to use renewable forms of energy to mitigate climate change. Germany's goal is 22% renewable by 2020, UK 15% and Japan 18%; the US in limbo as the Senate refuses to take up climate control though 27 states have mandated renewable minimums from 15-40% including California at 33% (source: Renewable Energy Policy Network). Let us hope for China and India.

"The world's energy system is at a crossroads. Current global trends in energy supply and consumption are patently unsustainable-- environmentally, economically, socially.... What is needed is nothing short of an energy revolution."
--International Energy Agency, 2008