Friday, August 17, 2012

CO2 Emissions Drop to 20-Year Low. A Cause to Rejoice?

A barely noticed (especially by climate scientists) report by the U.S. Energy Department Information Agency this month, stated that energy-related CO2 emissions in the U.S. for the first 4 months this year, fell to 1992 levels.

The report went on to indicate that the primary factor and reason is that cheaper (and cleaner)  natural gas led many power plants to switch from much dirtier coal burning (which also generates mercury in the atmosphere).

Evidently, many of the world's climate scientists didn't see the drop coming because it occurred as a result of "market forces" (according to an AP report) "rather than direct government action against carbon dioxide" - say by imposing carbon taxes, or gasoline taxes.

According to Michael Mann, a professor at Penn State University and Director of its Earth System Science Center, the shift is "a reason for cautious optimism" about ways to deal with climate change. He suggested that "ultimately people follow their wallets in dealing with climate change".

Maybe. While it is indeed true that coal -fired power plants produce more than 90 times as much sulphur dioxide (SO2) and five times as much nitrogen oxide and twice as much CO2 as those running on natural gas, we must bear in mind that most of this natural gas was obtained via shale gas drilling and fracking, which has often taken a fearful toll on water sources. (Especially at a time when nearly 57% of the U.S. watershed is already contaminated by assorted nasties such as potassium percholorate, aka rocket fuel. Cancer anyone? Breast? Prostate? Pancreas? Liver? We must be aware here that the "pocket book" saving elicited may return to bite us in a different way - as in higher medical and other costs!)

So the question remains: does this news warrant real celebration that we've suddenly won the war against global warming? Not really. First the data extracted pertains to only the first four months of this year. A better barometer would be for the entire year - so let's wait and see how the figures look for all of 2012. Next,  even a 20-year low for the whole year doesn't make much of a dent in the total CO2 already accumulated.

Recall the segment of The American Geophysical Union position statement(cf. Eos, Vol. 84, No. 51, December, 2003, p. 574):

"Atmospheric carbon dioxide concentrations have increased since the mid-1700s through fossil fuel burning and changes in land use, with more than 80% of this increase occurring since 1900. Moreover, research indicates that increased levels of carbon dioxide will remain in the atmosphere for hundreds of thousands of years."

  This is cognizant of the fact that CO2 accumulates because earlier depositions remain even as new burdens are added yearly! Thus, the CO2 warming we’re now experiencing is not the result of just one year – but 100 years’ progressive accumulation. The process may be described something like a series with terms being added, viz: to describe the CO2 content in the atmosphere by the end of this year, we must initiate the series with x= 1 (for 1912), viz.

CO2( 2012) = x_1 + x_2 + x_3 + x_4 +.............+ x_100

E.g. terminating at the last term 100 years later. Here each ‘x’ denotes the CO2 burden added for each year in succession.

Thus, the CO2 effect for a given year is not just for that year, but rather inclusive of the cumulative additions for all the years - starting up to 100 years before!  In more precise terms, a 4 month abatement that represents a "20-year low" - relative to say 1992, will register in the total scheme of accumulation as barely more than 1/300 of the total aggregation. By way of reference,  Terry Gerlach  in his paper Volcanic Versus Anthropogenic Carbon Dioxide  appearing in Eos: Transactions of the American Geophysical Union( Vol. 92, No. 24, June 14, 2011, p. 201) showed that typical yearly volcanic contributions amount to some 0.26 gigaton per year of CO2 compared to 35 gigatons per year for primarily anthropogenic sources. As noted therein:

"For a few hours individual volcanoes may emit as much or more CO2 than human activities. But volcanic emissions are ephemeral while anthropogenic CO2 is emitted relentlessly from from ubiquitous sources.."

Which means human activity is a vastly more significant source of CO2 and the major reason we are approaching a CO2 concentration (taken to be from 550- 600 ppm)that marks the threshold to the runaway greenhouse effect. Thus do we have an "ACM" or anthropogenic carbon dioxide CO2 multiplier calculated from time series data on anthopogenic CO2 emission rates.

Or to put it into a more concrete frame of description: the reduction of CO2 in the U.S. this year arising from 4 months of 'market forces" (i.e. driven by power plants changing to natural gas fracked from shale) was almost certainly nullified and eliminated by the gigatons of CO2 generated in the past three months from the massive forest fires burning in the American West - and now raging in the Pacific Northwest, after the ravaging fires that swept Colorado (and New Mexico)  in June.

This means things can only get worse and what we really need (by the end of the calendar year) is a total assay of all the CO2 generated in the country, from all sources,  not just minor "savings" for four months. To do anything less is to encourage people to live in that proverbial abode called a "fool's paradise".

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