See the Tabbed Pages for links to video tutorials, and a linked list of post titles grouped by topic.

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".

Wednesday, September 29, 2010

Today’s CO2-Emitting Devices Add to Tomorrow’s Global Warming

Note:  This posting discusses an article by Davis and coworkers.  The posting immediately following this one discusses a commentary by Hoffert on the Davis article.

Summary:  The world-wide transportation, space heating and electric generating installations currently in use will continue to produce new CO2 (greenhouse gas) emissions for decades, adding to global warming.  Imagine that as of today we abruptly cease to manufacture new cars, planes, furnaces and air conditioning, and stop commissioning new electric power plants.  Even so, existing facilities and apparatuses, given their expected service times, would add sufficient new CO2 to the atmosphere    that the global mean temperature would likely rise about another 0.6 deg C (1.1 deg F) from today’s level by 50 years from now.  In actual fact, however, addition of new fossil fuel-burning facilities will not cease, and indeed will greatly expand, making global warming even worse.  Accordingly it is imperative to transform the world’s energy economy to one that relies mainly on alternative and sustainable energy sources and on devices adapted to use them.

Introduction.  The world’s nations already have enormous numbers of cars, airplanes, power generating plants, and heating and cooling facilities installed throughout their economies.  Yet as a consequence of globalization and human aspiration, there is a desire, if not a need, to add even more such facilities and items, probably increasing their numbers by large factors in the remainder of this century.  These new additions to global CO2-producing capacity constitute a critical danger exacerbating global warming.

Atmospheric CO2 will increase in the next 50 years due to existing installations.  In the September 10, 2010 issue of Science, Davis, Caldeira and Matthews (Vol. 329, p. 1330-3; see Note 1) report an analysis in which they imagine that no new CO2-generating facilities are added in the next 50 years.  They assess the future production of atmospheric CO2 (committed CO2) and its effect on global temperature from only CO2-producing equipment already in place.  This assessment was carried out using available data for world-wide fixed sources (e.g. power plants, residences and work places) and transportation equipment. They use a commonly accepted global climate model to make their projections.

Their analysis predicts that the global concentration of atmospheric CO2 will increase from the present 390 parts per million (ppm; parts by volume of CO2 gas per million parts by  volume of air total), to a predicted maximum of about 412 ppm at about 2037.  (A sense of how much CO2 is produced by burning one tankful of gasoline can be seen here.)  After 2037 the predicted CO2 concentration falls slightly to about 408 ppm by 2060. (See Fig. 1C from Davis and coworkers below). 


Gt CO2 stands for gigatons of CO2, where 1 gigaton is 1 billion tons, and 1 ton is a metric ton, 1000 kg, or about 2200 lbs.  In Figs. 1A and 1B the number for each colored band is the total committed Gt CO2 for that band. 
© American Association for the Advancement of Science.  Presentation of this Figure  here is believed to comply with the "Fair Use" limitations (sections 107 and 108) of US Copyright law.

In greater detail, the incremental increase in CO2 concentration in the atmosphere year by year starts out high, as all the facilities and equipment are active. (See Figs. 1A (graphed according to energy sector)  and 1B (graphed according to country/region) from Davis and coworkers).   Year by year as installations reach the ends of their predicted lifetimes and are taken out of service (based on historical useful lifetimes of comparable equipment) the annual increments diminish more or less in a straight line, falling to no further increment by about 2046 (i.e., 36 years from now).  These increments are superimposed on a baseline of CO2 annual additions that remain essentially constant throughout the 50 year span arising from “non-energy” sources, which are exemplified by cement and steel manufacture, and agriculture.  For this reason the annual CO2 increments never fall to zero. 

Global temperature is predicted to rise from its present level in the next 50 years.  Davis and coworkers depict the current average global temperature as being about 0.7 deg C (1.3 deg F) higher than it was in preindustrial times.  They predict that as a result of the increased atmospheric CO2 concentration arising from existing installations (Fig. 1C above) the average global temperature rises slowly over the next 50 years, reaching 1.3 deg C (2.3 deg F) above average preindustrial temperature by 2060. (See Fig. 1D above). 

Further detail: Predicted upper and lower bounds.  In Fig. 1, predicted upper and lower bounds to the changes shown are given by the dashed lines in Figs. 1A and 1B, and by the red and blue lines, respectively, in Figs. 1C and 1D.  These are based on higher and lower assumed production levels for CO2 than used in the median analysis.

Significance for global warming.  Davis and coworkers show that existing CO2-producing installations and devices lead to seemingly modest further increases in atmospheric CO2 levels and predicted further global temperature increases.  There is no comfort in these findings, however (see the next blog posting describing the article by Hoffert).  First, these predictions are due only to existing facilities.  There is no doubt that many more power generating plants, automobiles, and home heating and cooling capabilities that produce CO2 will be built over the 50 years covered.  This is because many areas of the world are only now passing from “undeveloped” to “developing” status, and currently developing countries are adding to demand for these devices and installations as well.  Second, as Davis and coworkers point out, other activities that lead to more burning of fossil fuels were not analyzed, but are significant.  These include transportation fuel distribution infrastructure, and highway development.

Conclusion. Davis and coworkers conclude “satisfying growing demand for energy without producing CO2 emissions will require truly extraordinary development and deployment of carbon-free sources of energy, perhaps 30 TW [terawatts, or trillion watts] by 2050 [citations omitted]. Yet avoiding key impacts of climate change depends on the success of efforts to overcome infrastructural inertia and commission a new generation of devices that can provide energy and transport services without releasing CO2 to the atmosphere.”

                                                *          *          *          *

Note 1. Available online for a fee or through personal or institutional subscription.  Many public libraries, and university libraries open to the public, receive the journal.

Saturday, September 25, 2010

Denying Global Warming

Summary: Global warming due to increasing greenhouse gas accumulation is considered by many to be among the most serious challenges facing humanity in the coming decades. Crucially, global warming is driven primarily by humanity’s burning of fossil fuels that produce the greenhouse gas carbon dioxide to provide energy.  There are, however, many individuals who deny the menaces posed by global warming, or even more fundamentally, deny that global warming is an actual phenomenon operating on the earth’s climate at all.  Significantly, many of these deniers are in positions wielding considerable political or economic power.  Here we examine some rationales given for the denial of global warming and seek to refute them.

1. “If I can’t feel it, here and now, it must not be happening!”  Some may require that, in order to accept the reality of global warming, they have to experience warmer weather in their localities on a daily basis. Global warming, however, is not a weather phenomenon, but rather a climatic phenomenon.  We experience weather daily and locally where we happen to be, as our television weather experts remind us every evening.


But climate is the long-term averaging of weather as experienced on all seven continents and over the oceans on long time scales such as a year or more.  Nowadays these climate data are gathered from hundreds of continental and island land-based observation stations (see graphic below) and from the oceans using buoys

Land- and island-based observation stations. http://oceanworld.tamu.edu/resources/oceanography-book/evidenceforwarming.htm

and ships (starting about 1850) and nowadays also by satellite.  It is this long-term average in global temperatures that climatologists have shown unambiguously to be changing: the global average temperatures experienced over recent years have been inexorably increasing.  The graphic below shows the deviation in global mean temperatures from a reference temperature calculated by averaging the years 1961-1990, in deg Centigrade (the vertical scale runs from -1.08 to +1.08 in deg Fahrenheit).

The global temperatures are all below the mean reference temperature prior to about 1935, and increase above the reference dramatically after 1980 in a clearly unmistakable trend that exceeds the variations in each year shown by the “I”-shaped error bars. 

The increases to date may seem small by the layman’s reference, on the order of 1ยบ F for this global average.  Such a change at the local level, experienced by our denier, may be imperceptible given the wide fluctuations in daily or weekly weather.  On a global level, however, such seemingly modest changes will have profound effects. 

The West of the US has suffered extreme drought and a high incidence of forest fires for several summers, to extents that exceed expectations from earlier historical records.  Record high temperatures were recorded in Russia, and in Pakistan, this summer (2010), and the last 12 months (as of July 2010) have been the hottest on record.  The catastrophic flooding in Pakistan is highly likely to be correlated with increasing ocean temperatures, due to global warming, according to the U. S. Center for Naval Analysis and World Meteorological Association.  Some areas will experience greater aridity and drought.  Others will experience more precipitation because warmer ocean temperatures permit more water to evaporate into the atmosphere to subsequently precipitate as an increased amount of rainfall.

Thus, in summary, the appropriate assessment of whether or not global warming is occurring is not what a sole denier may experience on the ground in her daily life, but rather the broad regional and planet-wide climate patterns that develop over periods of one to several years. 

2. “Warnings of global warming are made by climate scientists who stand to gain personal advantage by inciting the people of the world to act.”  According to this conspiratorial hypothesis, climate scientists have serious conflicts of interest between their discussions of the public welfare and potential financial or reputational gain arising from their work.  Nothing could be further from the truth.

The practice of science is fundamentally driven by open inquiry involving the gathering and interpretation of experimental data (see Climate Science, Global Warming and The Scientific Method). Climate scientists, as most scientists practicing in what may be termed “basic” science, are preponderantly employed by universities, government agencies, and similar not-for-profit organizations.  They, and their employers, are not driven by motives of financial gain, but rather by establishing, verifying, and extending our understanding of the physical world that we inhabit.  Essentially all results made public in climate science pass under the scrutiny of peer review prior to publication.  In the peer review process, the editor of a journal to which a scientist submits a manuscript for publication sends the manuscript to two or three scientists who are expert in the field of the manuscript for critical evaluation.  Importantly, the peer reviewers remain anonymous to the authors of the manuscript.  A reviewer can accept the work as is, reject it outright, or require responses to certain criticisms he/she may develop prior to acceptance.

Peer review ensures that no biased points of view, or inaccurate scientific conclusions, enter the public domain.  In addition, in contemporary scientific practice, the publishers of most journals require authors expressly to identify any interests they have that may be construed as being in conflict.

On the other hand, political conflict against practicing climatologists arose during the administration of President George W. Bush.  This actually represents a perversion of any conspiracy theories proposed by deniers of global warming.  Several of the most prominent climate scientists employed by the U. S. government had their work, as well as their personal appearances, suppressed or sequestered, presumably because their views concerning the urgency of the impending global warming crisis conflicted with interests and/or policies that the administration wished to promote.  Thus rather than scientists profiting from their writings and speeches, it was the federal government during the Bush administration, their employer, that in reality engaged in conflicting practices for the benefit of its policy implementation.

3, “We’ve always burned fossil fuels to power our way of life.  Why can’t we continue doing so without constraint?”  Sentiments such as this are common in the U. S. and abroad nowadays.  They represent an attitude of complacency or willful persistence in continuing past behaviors, even in the face of overwhelming evidence of the reality of global warming brought about by human activities.

Yet such behavior is dangerously reckless when considering the future changes to our planet that global warming is likely to bring about.  There are several considerations militating against such complacency.  First, this lifestyle has not “always” been so.  Little more than 100 years ago technologically developed countries were just emerging from a pre-industrial way of life that had persisted for millennia.  While I’m hardly advocating a return to that state, it’s important to note that our present comforts only arose within the past 3-4 generations.  In developed countries, the ubiquity of cars, and of central heating and air conditioning, both major users of fossil fuel-driven energy, has been a reality for only the last hundred years or so.

Second, the rest of the world’s population, not to be left out, is clamoring to enjoy the benefits of advanced energy-driven lifestyles as well, and those people vastly outnumber the population of the developed countries.  This thirst to join the Western world in its comforts and conveniences leads to increased demand for energy, currently derived from fossil fuels, that is not merely additive, but is growing by multiples over very short time spans. 

Third, not only is the population base for energy demand growing, but in established economies the per capita demand for energy is growing.  One only has to observe the unending expansion of highway systems, the growth of air travel, and the increase in the number and size of homes that need to be heated and cooled, to understand how this is occurring.

This expanding demand for energy thus gives the lie to the complacency of continuing past patterns of energy use.  Past energy consumption has not been as high as it is now, and starting now will continue to grow at ever-increasing rates in the future.

4. “Global warming is quite simply a hoax.  The planet is not warming!”  These sentiments are problematic on several fronts.  First, such fervor takes on an air of unshakeable faith, such that the statement that global warming is a hoax becomes the conclusion, in support of which half-truths, misrepresentations and unsubstantiated findings are adduced, frequently after the fact.  Many who engage in this practice pretend they are following a scientific approach; in fact they are perpetrating a travesty of the scientific method. The objective practice of science requires the unbiased gathering of data, evaluation of the results gleaned from the data, and finally, statement of conclusions based on the results and supported by them. 

Second, the tenacity with which opponents of global warming hold such anti-global warming beliefs makes it very difficult to engage in discussion with them.  A belief held on faith can be quite unshakeable, and is very difficult to rebut using arguments based on the science of global warming.

Third, energy legislation in Congress intended to counteract global warming has failed to progress because of the stance taken by many congresspersons and senators that global warming is a hoax and is not happening.  The (U. S.) Virginia Republican party scoffed at Congressional Democrats supporting the cap-and-trade bill this past winter (Feb. 2010) when the capital was hit with serial record-breaking snowstorms.  Sen. James Inhofe has stated climate change is “the greatest hoax ever perpetrated on the American people."  He has cited the severe Washington blizzards of the 2009-2010 winter as evidence.  )  Sen. Inhofe continued to deny that climate change was responsible for the subsequent severe heat wave in Washington the following summer (2010), in direct contradiction to the National Oceanic and Atmospheric Administration's National Climatic Data Center which cited the vast array of scientific evidence showing increasing global temperature trends.  

The adamancy of the anti-global warming position espoused by these legislators is critically significant for impeding U. S., and global, progress toward mitigating the effects of global warming caused by man-made greenhouse gases.

Conclusion:  Arguments denying that global warming due to man-made greenhouse gases do not hold up to critical analysis, and to the unambiguous conclusions of the world’s climatologists (Intergovernmental Panel on Climate Change) convened by the World Meteorolgical Organization and the United Nations Environmental Programme.  It is imperative to embark on meaningful policies and practices to minimize the growth in global warming and to overcome its effects at the earliest practical time.

Tuesday, September 21, 2010

Light And Heat – The Greenhouse Effect

Summary:  Global warming is attributed to a greenhouse effect occurring in the atmosphere as a result of the accumulation of excess amounts of carbon dioxide, methane, nitrogen oxides and other “greenhouse gases”.  Sound methods of objective scientific investigation have shown that the excess levels of these gases is due to human activity, namely, the burning of fossil fuels that produce CO2 on combustion.  This blog posting provides an explanation of the greenhouse effect in general, and shows why carbon dioxide is a greenhouse gas.  A brief discussion is presented in the paragraphs immediately following.  Expanded explanations are found in the Notes further below that are referenced in the discussion.

The Greenhouse Effect.  The greenhouse effect refers to the fact that a glass greenhouse (or a car interior) maintains a warmer temperature inside the greenhouse than outside when the sun shines on it.  This happens because glass is transparent to sunlight, permitting the sun’s light to reach the inside of the greenhouse.  Some of the heat released by the incident sunlight is trapped by the glass, retaining much of the heat inside the greenhouse.

Colored objects convert visible light to heat. Whenever light from the sun strikes a colored object on the face of the earth, the object absorbs some of that light (see Note 1).  All light is actually a form of energy.  The energy in visible light that is absorbed by the colored object is re-emitted as heat energy, invisible to the human eye, called infrared radiation (see Note 2).

Greenhouses trap some of the heat radiation. In a greenhouse, as we noted, the glass lets the sunlight through.  Plants, soil and other objects in the greenhouse absorb the sunlight, and re-radiate heat energy as a result.  If these objects were in the open, the heat would radiate out into the atmosphere.  But in a greenhouse, the glass panes actually absorb a part of the heat radiation and don’t let it radiate back out.  The glass traps the heat inside the greenhouse, keeping all its contents warmer than the outside air.

Greenhouse gases trap heat in the earth’s atmosphere. Greenhouse gases such as carbon dioxide (CO2) in the earth’s atmosphere work in exactly the same way.  They are transparent to visible sunlight, but absorb some of the heat radiation in the infrared portion of the spectrum, retaining the heat within the atmosphere and emitting some of it back to the surface (see the graphic below, and Notes 3 and 4).


http://www.hotindienews.com/2010/05/19/1023923


Rising CO2 levels result in global warming. Over the course of the eons during which CO2 concentrations were constant in the atmosphere, temperatures were within a range that permitted life forms to develop and branch out on our planet.  But now, in a relatively short period on the geologic time scale, man-made CO2 arising from the burning of fossil fuels  is being added to the atmosphere.  Climate scientists are finding that the greenhouse effect of the added CO2 is increasing, making global temperatures warmer.  This effect has been most pronounced over the past 50 or so years, and especially so in the recent two decades.  The graphic below shows superimposed measurements of CO2 concentrations in the air and global temperatures from 1880 to 2004. 


http://oceanworld.tamu.edu/resources/oceanography-book/evidenceforwarming.htm

It’s quite apparent that the two trends are fully correlated with each other, showing that it is highly likely that the higher CO2 concentration is directly responsible for the warming trend because of the greenhouse effect.

Other gases are also greenhouse gases.  Among the most significant is methane, the gas of natural gas (see Note 5). 

Conclusion: From this discussion we understand how atmospheric CO2, methane and certain other gases behave as greenhouse gases, and that the greenhouse effect is increasing as we burn more fossil fuels and release more and more CO2 into the atmosphere.  The greenhouse effect is leading to global warming.  Thus it should be a high priority for all of humanity to minimize the burning of fossil fuels, and to develop programs that combat the effects of the higher amounts of CO2 already present.

*  *  *  *

NOTES

Note 1. We all know that white objects absorb little or no sunlight.  But consider the light from the sun that does strike an object.  Sunlight is made up partly of visible light of all the colors of the rainbow, from violet all the way to red; this is called the visible spectrum.  This is also seen when light passes through, for example, a crystal chandelier or a glass prism, displaying the rainbow spectrum.  This is shown in the graphic below.

Dispersion of visible light by a prism
Objects we perceive as having color, such as a green leaf, or the orange color of autumn leaves, absorb some of the colors in sunlight but reflect back the remaining colors (see the graphic below).   
 
Greenhouse0-mrnice.nl

Chlorophylls and carotenoids are the pigments in green leaves that give them their color.  The chlorophylls a and b in the leaf absorb the violet-blue and red ends of the spectrum, reflecting back the unabsorbed greens and yellows (the higher the line, the more light of that color of the spectrum is absorbed).  These unabsorbed greens and yellows are the colors we see.  The carotenoids absorb the bluish and greenish parts of the spectrum and reflect back the oranges and reds, which are the colors we see in autumn.  Black objects appear black because they absorb all the colors of the visible spectrum; we should consider the black to be actually the absence of any light whatsoever.  The visible light absorbed is radiated back as heat, or infrared light (see Note 2).

Note 2. It’s known from physics that light is actually a transmission of energy.  The energy absorbed  by colored objects (Note 1) is converted to a different part of the energy spectrum, the infrared spectrum (infra means below, meaning below the  red light of the visible spectrum), which is felt as heat.  The light contained in the visible, or rainbow, spectrum is not heat energy in and of itself.  Rather, colored objects feel warm in sunlight because of the conversion to heat, or infrared radiation (see the graphic below, showing the infrared portion in the spectrum of light radiation).  Black objects absorb the most light and so feel the warmest, while light shades absorb considerably less and don’t feel warm in the sun. 


Portions of the spectrum including the infrared and visible portions.

Note 3. Over the lifetime of the earth, as life forms emerged and spread, over more than a billion years, the earth’s atmosphere accumulated a certain level of carbon dioxide partly as a result of metabolism of carbon compounds by the living beings.  Through the eons that carbon dioxide has been recycled out of the atmosphere partly by photosynthesis, which re-incorporated it back into plant matter, or biomass.  In the history of the earth, these balancing processes maintained the carbon dioxide level relatively constant within certain limits of variation, such that up to the beginning of the industrial revolution the amount of carbon dioxide in the atmosphere was about 280 parts per million (ppm).  Today however, as a result of man’s burning fossil fuels for energy, the CO2 concentration is now about 380 ppm, and growing.

Note 4. Why is CO2 a greenhouse gas?  Most molecules behave as if they have a “color” in the part of the unseen light spectrum that transmits heat.  This is called the infrared spectrum (see the graphic in Note 2).  Different molecules have different “colors” in the infrared part of the spectrum, just like different substances having different colors to our eyes in the visible spectrum (such as the chlorophylls and carotenoids in the graphic in Note 1).  Atmospheric CO2, while permitting the visible light of sunlight to pass unimpeded through the air to the ground, does have an infrared “color”, and partially absorbs heat radiated back into the atmosphere from the surface of the earth after colored objects have absorbed sunlight (see the graphic below; here absorbed infrared radiation is indicated in the downward troughs, and transmitted or unabsorbed light is shown by the flat portions at the top). 


The absorbed infrared radiation is re-released in all directions, including back into the atmosphere and down to the earth’s surface.  The heat absorbed by the CO2 would otherwise radiate without hindrance into outer space.  Thus atmospheric CO2 retains a portion of the heat ultimately provided by sunlight via the re-radiation of heat from the earth’s surface.  This retained heat keeps the atmospheric temperature somewhat warmer than it otherwise would be.  In this way CO2 and other greenhouse gases act just as the glass in a greenhouse does. 

Note 5. Methane has an infrared “color” that is much stronger than that of CO2.  Molecule for molecule, methane is about 25-40 more effective in absorbing heat than is CO2.  For this reason, scientists working on global warming are very concerned about methane, although its concentration in air is less than 1% of the concentration of CO2.  This is why there’s an interest in reducing the amount of methane arising from dairy cows and other domesticated animals that chew the cud.  The bacteria in the rumen of these animals produce large amounts of methane that are belched out by the animals.  Methane is also sequestered as a solid crystalline ice hydrate in arctic tundras.  This methane originated from the decay of organic matter in the tundra’s vegetation.  As the tundra melts due to global warming, large amounts of methane are melted out of the hydrate crystals and released into the atmosphere, which contributes to warming even more.  This is one way that global warming is accelerating its own progress on Earth.

Friday, September 17, 2010

Blunting California’s Global Warming Solutions Act

Summary: Global warming due to man-made greenhouse gases arising from burning fossil fuels is a major and growing problem.  Objective scientific studies have clearly established that man-made global warming is a real process.  A warming planet is arguably already affecting climate and severe weather events around the globe.  It behooves the citizens of all nations to act dramatically to stem the addition of greenhouse gases to the air, and indeed to seek to reduce the amounts already present.  California acted unilaterally in 2006 to undertake such a program.  This program is now being challenged by a ballot initiative to be voted on in the November election.  If the voters approve this initiative it would strike a critical blow against combating global warming.

California’s Proposition 23 seeks to prevent the Global Warming Solutions Act from being implemented. The New York Times reported on September 17, 2010 that major financial backing for the initiative to block implementation of California’s unprecedented program to reduce greenhouse gas emission comes from wealthy out-of-state donors.  Proposition 23 on the ballot for November would suspend the provisions of AB 32 (2006), the "Global Warming Solutions Act" until unemployment falls below 5.5% or less for four quarters in a row.  Specifically, it would suspend the statutory requirement (see the next paragraph) that greenhouse gas emissions be cut to levels prevalent in California in 1990 by the year 2020.  The Proposition would also terminate the statutory emission reporting requirements and the implementation of programs to reduce greenhouse gas production by supplanting fossil fuels as an energy source with renewable energy sources.  The language of the Proposition makes unemployment during this time of economic hardship its apparent motivation.  Clearly, however, approval of the Proposition would preserve the demand for and consumption of fossil fuels, which would be to the advantage of currently operating energy companies.

The Global Warming Solutions Act.  In more detail, the Global Warming Solutions Act requires in part
(1)   monitoring and annual reporting of all major sources of greenhouse gas emissions,
(2)   accounting for greenhouse gas emissions arising in particular from the generation of electricity used in the state, whether generated within or outside the state,
(3)   establishing the level of greenhouse gas emissions that occurred in 1990 and assuring that greenhouse gas emissions be lowered to that level by 2020,
(4)   establishing rules and regulations by means of public hearings and taking into account the technological feasibility and cost-effectiveness in order to achieve the Act’s objectives, for electricity generation, petroleum refining and fuel supplies by Jan. 1, 2010, subject to exclusions for small businesses whose emissions fall below a level to be determined; the rules must be adopted by Jan. 1, 2011, and
(5)   affording the option of adopting regulations that establish a market-based system with successively lower annual limits to greenhouse gas emissions in order to achieve the objectives of the Act.
Current progress and status of implementing the Act may be accessed here

The Global Warming Solutions Act has been actively supported by the Republican Governor, Arnold Schwarzenegger.  The 1990 limit represents about a 25% reduction in greenhouse gas emissions from the level estimated for the year of passage, 2006.  California’s progressive initiative in this regard makes a significant contribution to modalities for reducing greenhouse gas production from fossil fuel combustion in the U. S.  It clearly far supersedes efforts at the federal level, which are held in stalemate in Congress.

Opponents of the Act.  Proposition 23 is written in terms of unemployment statistics, suggesting that its proponents may be interested in protecting or promoting jobs in California.  According to the U. S. Bureau of Labor Statistics the last time that the California unemployment rate fulfilled the criterion set out in Proposition 23 ended July 2007, and is not likely to return to such low levels for many years.  Yet the backers of Proposition 23 appear to have little interest in the welfare of workers.  Rather, the New York Times reports that several out-of-state oil companies are contributing millions of dollars in support of Proposition 23.  The interests of these companies are best served by defeating any initiatives promoting alternative energy development.  The oil billionaires Charles and David Koch of Kansas have contributed $1 million, and the total for energy company contributions is $7.9 million, most of which has come from outside of California.  According to an extensive list of supporters of Proposition 23 Valero, Tesoro Companies and Flint Hills Resources alone have donated $6,575,000.  Other major contributors include other energy companies, the California Trucking Association, and the Howard Jarvis Taxpayers Association, which is responsible for several California initiatives to limit taxes.

Supporters of the Act. The Global Warming Solutions Act is supported by members of both parties.  Opponents of Proposition 23  include the group “Californians for Clean Energy and Jobs”, whose honorary co-chairman is George Schultz, Secretary of State under Pres. Ronald Reagan.  According to the linked article, he has stated “While some companies in California have said they’re worried about the cost of the planned greenhouse gas limits, the new regulations will boost the state’s economy by creating 'clean-tech jobs’".  Opponents of the Proposition have donated about $5 million.  These include Thomas Steyer, the National Resources Defense Council and the Environmental Defense Fund.  Thomas Steyer is a San Francisco hedge fund manager who was an active fund raiser for Barack Obama’s presidential campaign.

Conclusion. It’s important to weigh the effects of approval of the Proposition versus maintaining the Act in force in deciding how to vote in November.  The outcome would have major consequences for combating global warming in California.

Monday, September 13, 2010

Climate Science, Global Warming and The Scientific Method

Summary: Climate science investigations related to global warming are undertaken entirely according to the scientific method, which precludes developing preconceived conclusions and seeking biased data in support of those conclusions. Of two possible ways of conducting scientific investigations, most climate science research can be characterized as being descriptive in nature, and generally cannot be carried out with the use experimental controls that can be set by the investigator. The resulting data enhance our understanding of the global climate, and serve as the basis for models predicting future climate behavior.


Public perceptions of global warming. The American public is dramatically divided over the question of global warming. Many accept the findings that have been developed by our scientists as being accurate, and being based on sound scientific principles. Others oppose the notion that global warming, due to human activity and originating primarily in the burning of fossil fuels, is “real”, i.e. that the planet is actually undergoing an abrupt change in its climate due to greenhouse gas accumulation.

A simplified classification of scientific investigations. Climate scientists, as members of the broad community of physical and biological scientists, undertake their studies according to well-established principles of scientific investigation. Some of these principles are described here. This characterization is necessarily simplified here for the benefit of the general public.

Science is undertaken as an objective, unbiased inquiry. First, all scientific investigation is undertaken as an open inquiry. What this means is that a scientist engages in an investigation with an unbiased mind, avoiding any prior expression of what the result of the investigation should reveal. Valid science is not conducted by adopting a conclusion at the outset and seeking out those particular findings or results that bear out the preordained conclusion stated at the outset, or by designing a study in such a way as to provide those results.

Hypothesis-driven experimentation. In the simplified view presented here, scientific investigations in general can be classified in one of two distinct ways. In the first, a scientist will initially formulate a hypothesis, and conduct experiments to confirm or deny the accuracy of predictions based on the hypothesis. Hypotheses usually build on experimental results already in hand, and are constructed around particular unproven statements or assumptions about the experimental system being studied, using experimental variables subject to the control of the experimentalist. Experiments are then devised that change one or another of the variables to characterize the effect of the variation on the outcome of the study.

Hypothesis-driven experimentation is readily devised to include a second, reference, condition of the system, which is intended to characterize the system in the absence of the variation imposed in the first experiment. This reference is usually called a “control” condition, or the experimental manipulation involving the reference is called the “control” experiment, or just simply the “control”. Then two parallel experiments are conducted in which the variable is changed in the first experiment but is held constant in the control system. The results obtained in the first, varied, system are compared with those of the control system, and an objectively valid conclusion is drawn based on the finding of a difference, and/or on the amount of the difference, between the experimental system and its control. At this point, the investigator will conclude that the hypothesis is correct if the results bear out the predictions made according to the hypothesis, or else will conclude that the hypothesis was incorrectly drawn if the results contradict the prediction of the hypothesis.

Hypothesis-driven experiment, with a control for the variable C.
Descriptive investigations. A second class of scientific investigation can be called a descriptive study. Descriptive studies in general will examine an experimental system, providing a description of its nature without a preliminary formulation of a hypothesis. The scientific contribution consists in developing the new information, the new characterization, that was not available before. Generally descriptive investigations cannot be carried out using parallel controls, for any of a variety of reasons. Frequently, for example, a system cannot be contained in a sufficiently controlled environment for the scientist to knowledgeably and definitively to alter a single, particular variable. In such a situation, it may be necessary to consider the state of the system at some earlier time, and compare it with an altered state at some later time, to compensate for the inability to use controls. This is to be contrasted with the hypothesis-driven investigation, where single variables are changed under the control of the investigator, and parallel control and varied experiments are readily carried out. Examples of descriptive investigations include studies of volcanic activity, or of earthquakes, or studies in the changes observed in a series of paleontological fossils, or in current biological species variation.

Descriptive experiment showing the time dependence of the value of a variable.
Climate science is primarily a descriptive undertaking. Clearly climate studies such as those that characterize global warming fall into the class of descriptive investigations. Considering climate as a globe-wide phenomenon, the experimental system in question is necessarily the entire planet. In essence the excess burning of fossil fuels since the beginning of the industrial revolution has converted our entire planet into a single massive scientific experiment, one being conducted in the absence of a control. Since climate scientists cannot conjure up a parallel planet on which burning of fossil fuels is not occurring, much of climate science cannot be classified as being hypothesis-driven. In addition, studies undertaken in the framework of global warming investigations are precisely descriptive in nature. Various characteristics of the climate and of its effects are measured, catalogued, and trends with time are characterized. Some examples of measurable variables include land surface temperatures measured at locations across the planet, ocean water temperatures at the surface and at various depths, wind speeds and direction near the surface and at higher altitudes, and CO2 concentrations in the atmosphere and dissolved in ocean waters. Being descriptive, climate science and the study of global warming are necessarily objective in nature because the data collected are obtained in a totally naรฏve fashion. If conducted correctly, there cannot be any preconceived or prejudged result created before the fact, which may be sought to bias the outcome.


The time dependence of properties measured by climate scientists. Since climate science is a descriptive process, and control systems are not available, climate scientists draw conclusions from the results of the data collected based on the time development of those data. Thus, if there be a control experiment in climate science, it is the state of the planetary variables, such as temperature, atmospheric concentrations of CO2, and so on, that existed at an earlier time, and the trends for those variables as time advances up to the present. Here again, it is important to emphasize that all such measurements are conducted in an unbiased way, i.e., that the data collection is a naรฏve process that is not influenced by preconceived ideas about what those data should be.

Data-driven models are used to predict future trends. The contentious aspect of global warming and climate science, to the extent that it may indeed be contentious, is developing predictions of the future behavior of the climate in response to the burning of fossil fuels, and the consequent accumulation of atmospheric greenhouse gases. The models used in these predictions are extremely complex. They are formulated in advanced mathematical terms that require massive computational power to implement them, and to arrive at predictive results. The models use existing experimental data as a basis, and embody various ways of characterizing future climate changes that assume that certain climate processes will prevail over the predicted time frame. Climate scientists recognize that the details of these predictions may differ based on the assumptions made, and that there may be a range of probable outcomes from one model or another. What is certain, however, is the overall conclusion that continued accumulation of greenhouse gases in the atmosphere will have detrimental effects on the global climate as the decades pass. Importantly, sound principles employing the scientific method have been used to characterize our planet’s climate to date, and the best scientific models are being implemented to try to understand the future trends of our climate.

Saturday, September 11, 2010

Invisible Energy

Summary: Since CO2 is odorless and colorless, we cannot grasp how much of this greenhouse gas we generate in our daily activities. Here, I present some graphics and descriptions that easily permit such an understanding. An inevitable conclusion is that we must all strive to minimize our activities that contribute to the accumulation of CO2 and other greenhouse gases.


Why does a large fraction of the American public deny the truth of global warming? Well, for one thing, what is out of sight is out of mind. We heat our homes with gas or oil that we do not see. Once in a while, if we look inside the furnace, we’ll marvel at the beauty of the cool blue flame. But we have no sense of how much gas is actually flowing, or how much oil we’re actually consuming. So we, the warmed citizens of this country, can’t appreciate how much of that fossil fuel is actually being burned to CO2 gas and released into the atmosphere.


Likewise, we consume electricity in our homes for lighting, powering appliances, for air conditioning in the summer, and in some cases for space heating instead of gas or oil heating mentioned above. Here too, even more so, we as consumers are fully and effectively shielded from the vast amount of carbon based fuels burned to produce the electricity we use. Almost all electric power in the US is produced from coal and natural gas. Who among us has any sense of the vast tonnage of coal, or the millions of cu. ft. of gas, that are burned (with relatively poor efficiency) to generate that power? Electricity is delivered to us through wires hidden from view inside the walls of our houses, and of course we can’t count the electrons coursing through those wires to our homes as we go about our daily routines.


Third, gasoline- or diesel-fueled transportation effectively conceals any sense of consumption of liquid. We pump an invisible liquid through an opaque hose into an unseen gas tank, that mystical internal storage compartment in our cars, trucks and buses. But we really can’t grasp how much we’re pumping in, or how much it weighs. Gas stations aren’t equipped with auto scales so that we could actually measure the weight of gasoline added by filling up. Further, we have no sense of how much CO2 is actually produced when that weighty liquid is burned to CO2 and released into the atmosphere. So there’s no sense of the CO2 burden we’re imposing on the atmosphere with every fill-up at the gas station. And of course, that CO2 vapor is colorless and odorless, so we don’t sense the final product of our transportation consumption either.



Here’s a simple illustration intended to help us grasp how much CO2 we actually release when driving a car. Suppose your car is representative, and takes about 15 gallons of gasoline to fill up the tank. When you do so, you’ve added about 84 pounds of gasoline liquid (see the first figure, below).
Weighing a tankful gas in your car on a fulcrum balance.


When burned in your engine (and after the exhaust passes through the catalytic converter of the car) you’ve produced about 260 pounds of CO2. (You’ve also produced some water vapor, but that’s not significant for our discussion about the greenhouse gas effect.) CO2 can be liquefied by applying extra pressure and cooling it; as a liquid these 260 pounds would measure about 69 gal. If that were kept in an on-board pressurized tank, it would have to be much larger than the gas tank that you filled at the pump.


But in reality, without compression and cooling CO2 is a gas. These 69 gal. of liquid CO2 would actually occupy about 16,400 gal. of gaseous volume, if that volume contained the pure CO2 and no other components of air (see the second figure, further below). But in today’s atmosphere, the distributed concentration of CO2 in the air is about 360 parts per million (ppm), meaning that in 1 million gallons, for example, of air volume, 360 gallons would be CO2 (thus, 360 ppm) and the remainder would be the other components of our atmosphere, such as nitrogen, oxygen and water vapor. So if we now equilibrate the 16,400 gallons of CO2 vapor from burning our tankful of gas into the atmosphere, and considering a cubic volume, this CO2 would be distributed into a cube about 180 feet on a side. For comparison, most mature trees are about 60-80 feet tall (see the second figure); and a building this tall would have 12-18 stories.

Virtual cube 180 feet on a side showing the volume that would be occupied by liquid CO2,
by the same amount of pure CO2 gas, and by distributed skunk-odor-linked CO2
produced by burning one tankful of gasoline.  A mature tree is shown for comparison.
Now, suppose we could attach the smelly molecule that skunks emit to every CO2 molecule. The result of burning 15 gallons of gasoline from one fill-up at the gas station would produce a cube of skunk-smelling gas that is 180 feet on side. In fact the smelly odor of skunks is a very strong odorant; usually we can detect a few ppm in the air. So if you entered this virtual cube, with skunk odor at the 360 ppm concentration that characterizes atmospheric CO2, you would be overwhelmed, and might even start feeling sick!

If you fill up your tank once a week for 1 year, you could envision lining up these cubes end-to-end. In that 1 year period, you’d be making a rectangular volume that is 180 feet wide, 180 feet tall, and almost 9,500 feet long. Thus, with our imaginary skunk-smelling CO2, you’d create a strongly skunk-smelling rectangular volume that is almost 2 miles long at the end of 1 year of driving.

This detailed illustration covers only our transportation usage of fossil fuels. But our other energy needs mentioned at the beginning of this article obviously also contribute to producing atmospheric CO2, so comparable volumes of gas, and in our illustration, skunk-smelling gas, would be produced by each one of those sources over the course of a year. The numbers will differ, but the general effect for each contributing source will be the same. Enormous volumes of equilibrated carbon dioxide are produced by each one of us as we go about our daily activities.

Global production of atmospheric CO2.  This illustration needs to be multiplied by the number of people in the U.S., or rather, since global warming is indeed a world-wide phenomenon, multiplied by the total contributions from all the people in the world. In general, our fossil fuel consumption is increasing with time, both because the population in general is increasing, and because in developing countries the per capita consumption of fossil fuels is increasing dramatically. So it’s useful to imagine our skunk-smelling CO2 gas covering this virtual earth, and growing stronger in odor every year. Indeed, we, the global population of humans, are currently adding 2 ppm of CO2 to the atmosphere every year.

The world’s CO2 burden is like a bathtub with a drain and a faucet. If we add water to this bathtub with a strong stream but open the drain only a little, it’s evident that the level of water in the tub will keep on rising. It’s the same with the CO2 in the atmosphere. There’s not much place for the added CO2 to go to in order to exit the atmosphere (except the oceans), and by our activities we keep adding CO2 to it, more than the oceans can absorb.


Conclusion. From this illustration, it’s clear that each one of us is contributing to the worsening of global warming with each energy-dependent activity that we undertake. We all have to go about our daily routines thinking of ways to reduce the burning of fossil fuels in the maintenance of our life styles. There really is no other answer to the problem that increasing atmospheric CO2 exacerbates global warming.