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This blog is expressly directed to readers who do not have strong training or backgrounds in science, with the intent of helping them grasp the underpinnings of this important issue. I'm going to present an ongoing series of posts that will develop various aspects of the science of global warming, its causes and possible methods for minimizing its advance and overcoming at least partially its detrimental effects.

Each post will begin with a capsule summary. It will then proceed with captioned sections to amplify and justify the statements and conclusions of the summary. I'll present images and tables where helpful to develop a point, since "a picture is worth a thousand words".

Tuesday, October 12, 2010

Why We Need A Massive Effort for Alternative Energy

Summary:  Previous postings (http://warmgloblog.blogspot.com/2010/09/todays-co2-emitting-devices-add-to.html; http://warmgloblog.blogspot.com/2010/10/we-need-to-achieve-alternativesustainab.html) discussed the current status of global warming arising from man-made greenhouse gas emissions arising from man-made greenhouse gas emissionsarising from man-made greenhouse gas emissionsarising from man-made greenhouse gas emissions.  Davis and coworkers have shown that even if installation of all new energy facilities worldwide that rely on fossil fuels were to abruptly stop right now, the continued emissions from existing facilities and items would continue feeding new greenhouse gas (mainly carbon dioxide, CO2) into the atmosphere, and continue to lead to further global temperature rise.  In contrast to this hypothesis, Hoffert, in his commentary on the Davis article, emphasizes the very dire situation that we will actually face in the future.  Recent predictions of future global warming from the United Kingdom and the United Nations suggest that average global temperatures could rise 4 deg C (7 deg F) or more from today by the end of the century.  Such a drastic change in climate would lead to serious unfavorable effects on human populations around the world.  Therefore massive governmental and private programs are needed to counter these trends and help stabilize the earth’s temperature.

Introduction: Before the industrial revolution, the atmospheric concentration of CO2 was relatively constant over the years, maintaining a “virtuous cycle” of CO2 production and removal.  Green plants undergoing photosynthesis convert atmospheric CO2 into cellulose, starches and soluble sugars.  On decay or as nutrients for animal life, this vegetation releases CO2 back into the atmosphere.  Animals, including humans, that feed on green plants or on other animals likewise metabolize their food for energy, thereby releasing CO2 as the end product.  Still further, humans burned surface vegetation for energy, also producing CO2, for cooking and heating.  These opposing processes went on in an endless cycle for eons, maintaining the atmospheric CO2 concentration relatively unchanged.  During this period the concentration of CO2 in the air remained at about 280 parts per million (ppm; molecules of CO2 per million molecules of all the gases present in air).

The industrial revolution broke the CO2 virtuous cycle.  Beginning in the mid 1800’s humanity began burning fossil fuels (coal, oil and natural gas) to provide additional useful work (the steam engine; the internal combustion engine) on a scale much larger than had been provided by the human body and domesticated animals.  Some anecdotal examples include railroads, factory mills, and electrical power generation.  This released new, unbalanced amounts of CO2 into the atmosphere.

Modern usage of fossil fuels.  In recent decades the use of these energy sources has expanded exponentially (i.e., increasing by multiples, rather than merely by addition).  Briefly, this is due to the following factors.  Our modern lifestyle favors extensive individual use of personal cars burning fossil fuels, with its underlying demand for highways to accommodate them.  There is a strong trend to live in larger homes that require more energy for heating and cooling.  Work spaces likewise have expanded greatly with still more needs for heating and cooling.  In developing countries, especially China and India, there is strong pressure for the populace, starting from minimal energy demands akin to the pre-industrial revolution period, to join the middle class with all the energy demands summarized above.  For example, China has been adding about two new coal-fired electricity plants a week for many years, since coal is abundantly available domestically (Library of Parliament of Canada, F. Beauregard-Tellier, 2007) .  In summary, on a world-wide scale, there has been profound expansion in energy demand, and fulfillment of that demand using fossil fuels. 

Increased CO2 will produce large increases in average global temperature.  This unprecedented growth in fossil fuel usage has caused a concomitant increase in atmospheric CO2 concentrations, which exceed the level that prevailed before the industrial revolution began.  Currently the CO2 concentration is about 390 ppm (Davis, Caldeira and Matthews, Science Vol. 329, pp. 1330-3, 2010; see Note 1), much higher than the level that prevailed prior to the industrial revolution; it is growing at about 2 ppm each year because of the expanded demand described above.  The present CO2 concentration has already led to increased global average temperature of about 0.9 deg C (1.6 deg F) over the temperature prevailing prior to the industrial revolution (Davis and coworkers). 

The United Kingdom National Weather Service (Met Office)  reported in 2009 that emissions are proceeding at a higher rate than was thought earlier.  It predicts that the global average temperature could be 4 deg C (7 deg F) higher than today (note: 4.7 deg C higher than preindustrial revolution times) by 2100, using a “high-end emissions scenario”.  Global climate patterns are such that polar regions and certain desert areas will warm more than others (see the graphic below).

Comparison of surface temperature projections from the high-end emissions scenario, without carbon cycle feedbacks. Temperature increases between 1961-1990 and 2090-2099, averaged over all high-end members. (United Kingdom National Weather Service).



The color coding in this graphic, superimposed on a map of the globe, is intended to show the extent of the increase in temperature in deg C above the baseline averaged over the 30 years from 1961-1990, that may be reached by the decade of 2090-2099.  The predicted temperature increases are shown starting with violet-purple shadings for predictions less than 1 deg C (1.8 deg F), up to strong reds and crimsons for predictions in the range 12-16 deg C (22-29 deg F).  The graphic shows that changes are greatest over the Arctic and northern temperate regions.  These results are in broad agreement with predictions made in 2007 by the Intergovernmental Panel on Climate Change (IPCC) , the United Nations consortium of thousands of climate scientists from around the world.

Negative effects of increased global temperatures.  Both the Met Office report and the IPCC analysis point out that higher average global temperatures of such magnitude will produce negative consequences for the wellbeing of humanity, including
Increases in high temperature extremes,
Increased extents of heavy rain and snow,
Melting of glaciers, snow and ice cover, and polar sea ice, leading to even more warming by direct absorption of sunlight, and to a significant rise in sea level, and
Decreased rainfall in regions closer to the equator such as Africa, Central America, the Mediterranean area and Australia.

A major reorientation of energy policy on a worldwide basis is called for.  The economic and social impacts of the predicted worldwide increases in the temperature of the climate are potentially severe in many regions of the world where large human populations live. In view of these effects, massive national and international projects are called for at the earliest possible date to minimize the effects of global warming, both already occurring and, more importantly, those predicted over the rest of this century.  Hoffert has characterized this as requiring a “Manhattan project”-like effort, referring to the massive U. S. program during World War II to develop the atomic bomb.  Another analogy might be the intensive U. S. space program to land men on the moon.  Only massive efforts on such scales, involving both governmental and private endeavors, can succeed in displacing all the fossil fuel-dependent installations world-wide with alternative technologies that fulfill our demand for energy without adding greenhouse gases to the atmosphere.


Note 1. Abstract available online free, or the full article for a fee or through personal or institutional subscription.  Many public libraries, and university libraries open to the public, receive the journal.

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