Rome Didn't Fall in A Day.









Objective Truth Exists, and is Accessible to Everyone.

All Human Problems can be Solved with Enough Knowledge, Wealth, Social Cooperation and Time.


Photo: Rusty Peak, Anchorage, Alaska


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Saturday, December 19, 2020

Doug's Laws

 A few months ago, I posted a reply on social media, with a comment that I called "Doug's Law #271". 
"There’s a precursor event to every disaster, if anyone is paying sufficient attention."  A friend, taking me seriously (big mistake) asked to read the other 270, which of course, didn't exist.  

After a little thought, I decided it would be worthwhile to make a list of life lessons and insights.  Some of these might seem cynical, obvious or trivial.  As another friend often says, your mileage may vary.  But for what it's worth, here's the list of Doug's Laws.

1)  All human problems can be solved with enough knowledge, money, social cooperation and time.

            -  Modified from David Deutsch.

2)  On a beach made of white seashells, the dark shell is the prettiest.  On a beach of dark seashells, the white one is the prettiest.  Beauty involves rarity.  

      The sunset is beautiful because it is brief and different than the other colors of the day.

3)  Objective truth exists and is generally accessible to everyone.

4)  Progressive risk-taking always ends in disaster.

Examples of progressive risk-taking include, “We’ve taken chances before, and it’s always worked out all right”, or “We have launched successfully twenty-four times; what can go wrong?”, or “You didn’t get pregnant the last time”.

You can fit a car through a narrower space than you expect until you can’t.

You can go farther than you think on a tank of gas until you can’t.  This is especially important in small airplanes.        - FAA Accident Report, circa 2009

5)  You have to learn to cooperate when paddling a canoe.

6)  We should judge God according to standards of reason and justice.

                - Modified from David Deutsch.

7)  The existence of war causes me to question the existence of nations as an organizing principle for humankind.

8)  Kindness is best, and most needed, when it is completely unexpected.

9)  I live in the Middle Ages, a time of war, disease, superstition and ignorance.

The Middle Ages will end when humankind is no longer organized into nations, when infectious disease is conquered, when most people no longer believe in religion and when education provides understanding, instead of belief and knowledge.

10)  Humans are a uniquely improbable, intelligent and capable species with no known analogs in time and space.  There is no evidence of another sentient and capable species in the 4.5 billion year history of earth.  There is no evidence of another sentient species in the galaxy.  We should make the most of our abilities.  We have the opportunity to become something more than we are today.

11)  It’s critically important to know when the rules have changed.

 Most Jews in 1930s Europe didn’t realize that the rules had changed.

12)  Three out of six people are completely honest.

  Two out of six will bend the rules to their advantage.

  One out of six people will cheat.

                - From experience as an internal auditor, an unscientific sample.

13) The great ethical debate of the next century will be what rights to give to sentient machines. 

The great ethical debate of the following century will be what rights to give to sentient humans.

14)  Justice delayed is injustice.

15)  You can’t mop the floor clean with dirty water or a dirty mop.

16)  Ends and means are the same.  There are no good ends achieved though bad means.

                                - Modified from Jacob Bronowski.

17)  No one is solely responsible for their own success.  Everyone is helped by other people along the way, and by the schools and institutions that enable them to succeed.

No business is solely responsible for its own success.  Every business is only successful because society has created a landscape of fair opportunity, physical and commercial infrastructure and a legal framework that enable the business to succeed.

Successful individuals and businesses have a responsibility to pay forward a portion of the profits of their success, so that others can also succeed.

18)  Anything worth doing requires practice.

19) You improve what you measure.

                 - Ralph Dartez

20)  You can’t write unless you have something to say.

Decide what to say before you write.

21)  Say the most important thing first.

                   - Ed Buchwald

22)  Anything you write will be improved by an editor.

                       - Renee Frazee

23)  If you don’t have a better idea, it’s time to shut up.

24)  Explanations matter.

Science is a matter of finding explanations.  An explanation is the identification, observation, measurement and communication about some process that changes physical reality.  Explanations follow the structure of language, with objects, actions and descriptive modifiers.

                - Synthesis and expansion after David Deutsch, Jacob Bronowski and Ed Buchwald.

25)  Empiricism isn’t science; it only works within the range of previous experience.  A good explanation has reach; it works outside the bounds of prior experience and extends to unexpected domains.

                        - Modified from David Deutsch and Jacob Bronowksi.

26)  People think and identify in dualities: Pepsi or Coke, Communism or Democracy, mountains or seashore, truth or falsehood, good or evil, Republican or Democrat.  Reality is more complicated.

27)  Scientists come in two types, experimentalists and theoreticians.  Consider Aristotle vs. Plato, Galileo vs. Newton, Michelson vs. Einstein, Edison vs. Tesla.  Neither can progress without the other.

28)  I’ve noticed a clear dichotomy in how people think.  It corresponds to whether they fit the “sensing” or “intuitive” types in the Myers-Briggs personality system.  The sensing individual only believes what he’s seen and doesn’t look for underlying causes.  The intuitive individual seeks to understand what he hasn’t seen and expects underlying causes.  This distinction seems to represent the some of the biggest differences in human outlook.

29)  There is a hierarchy in the ways that people comprehend the world: Belief, Knowledge and Understanding.  Belief and Knowledge fail more often than Understanding.

30)  People hate to let go of knowledge they learned as a child.

31)  Anyone or of sufficient intelligence should be able to independently derive the golden rule.

Some animals are sufficiently intelligent.  Some people are not.

32)  People who don’t give respect don’t deserve respect.

33)  Democracy and free enterprise only work in a society with high integrity and regard for truth. This is concerning for the United States in 2020.

34)  Rome didn’t fall in a day.

35)  Anyone who can’t face the world without a gun is either a bully or a coward.

36)  Being a manager is largely about being a life counselor.

37)  At any given time, one out of ten people is in an existential crisis, and has told somebody about it.  Another one out of ten people is in crisis but hasn’t told anyone yet.

38)  Being a manager is like being a custodian.  You stay at the office after everyone else has gone home and clean up the mess that people made during the day.

39)  Always learn the name of the custodian and thank them by name.

40)  Always greet people by name.

41)  People who think like dogs make great employees. 

        People who think like cats wind up in prison.

42)  Every small child is a genius in terms of learning, memory and creativity.

43)  Every small child instinctively understands that this moment will never come again.

44)  Amateur music is good training for life; you learn to appreciate the good notes and ignore the bad ones.

45)  It’s always darkest just before you stub your toe and fall down the stairs.

46)  People are at their greatest risk of a tragic accident when they are on vacation or having fun.

47)  The enjoyment of a bit of food is often inversely proportional to its size.

48)  Get rid of commas and extra words whenever you can.

49)  When you’re hiking up a mountain, most of the way you can’t see the top.

50)  Always minimize the weight you are carrying when hiking.  You will enjoy the hike much more.  But in dry country, always carry enough water.  You can make that a life metaphor if you like.

51)  It’s best to start hiking uphill and come down on the way home.

Also, start biking, canoeing or kayaking into the wind, and return with the wind at your back.

52)  Always check the gas when you start an engine.

53)  People consciously and unconsciously signal their status to other people.

One of our strongest signals is gender identity.

54)  Women usually wear mittens.  Men usually wear gloves.

 Nothing they say about it explains the dichotomy.

55)  If it’s important, write it down now.

56)  The more hours I spend outdoors, the better I sleep.

57)  For every proverb, there’s an equal and opposite proverb.

For every piece of advice, there’s an equal and opposite piece of advice.

                        - Steve Robbins (son).

58)  A good question carries with it the key to its own solution.  – source unknown

59)  When a reporter asks you for a comment, they’ve already decided what you are going to say.

60)  No reporter is really your friend.

61)  Propaganda works.  Confirmation bias is a very powerful force.  Confirmation bias combined with propaganda forms a feedback loop leading to unreasonable denial of truth.

62)  Most people are not interested in seeing both sides of an issue.

63)  Most politicians only know how to get elected and have no idea how to govern.

                - Peggy Robbins (Mom, b. 1926)

64)  It is impossible for a politician to remain completely independent of the interests of his campaign donors.  This is the reason for campaign finance reform.

65)  When there’s only one way to say the truth, that’s how you have to say it.

66)  Truth is necessarily an approximation, operating over a given domain, and with a degree of uncertainty.  But uncertainty does not mean falsehood. Objective truth (not absolute truth) exists.

67)  Art is the deliberate creation of something that produces an emotional response in another person. Art is an intentional form of communication.  Art requires an artist and an audience.

68)  The personality of a dog usually says something about the personality of its owner.

69)  Everyone working a full-time job deserves to earn a living wage.  A living wage is enough to comfortably raise a family. 

70)  A dog’s owner will never understand that the dog’s behavior toward its family is different than the dog’s behavior toward a stranger.

71)  All cats are alike, which is why tigers like to sit in boxes. 

        Since all cats are alike, it’s worth remembering that the biggest cats would eat you.

72)  Every database has errors.  The larger the database, the more errors there are.

73)  Every question from a vice-president begins with “what” or “how”.  Every question from the president begins with “who”.

74)  The potential return from cutting costs is one-fold.  The potential return from growth is unlimited.

75)  There is value in redundancy.  Redundancy provides resiliency, optionality, innovation and quality control.  These benefits usually outweigh the costs.

76)  There is value in diversity – of people, of systems, of approaches to problems.  Like redundancy, diversity provides resiliency, optionality, innovation and quality control.  

77)  Every system has friction and inefficiencies.  A rigorous program of eliminating inefficiencies may impair the primary function of the system.

78)  The benefit of a risk decision should first be weighed against the impact of the potential loss, without regard to probability.

79)  There’s a precursor event to every disaster, if anyone is paying sufficient attention.

80)  The most common cause of failure for risk models is correlated risk.  This was the cause of the financial crisis of 2008.  The second most common cause is neglected experience.

81)  “You only think you’ve found the endpoint.”    – Vic Beghini, President of Marathon Oil.

        In any distribution there’s always a possible realization beyond what you have sampled.

        In any situation, it’s possible for things to be worse.  (Note: Beghini was right.)

82)  Variables in one dimension have a normal distribution.  Variables in multiple dimensions (either physical dimensions or the product of one-dimensional variables) have a skewed, log-normal distribution.  The greater the skew, the more likely the variable is of a higher dimension.

83)  Most real-world distributions are log-normal in the middle, but distorted on the tails.  Distribution tails may be truncated by physical limits or fattened by some parameter outside of basic model.

84)  No one can properly assess very low probability or very high probability events.  This is partly due to sampling theory and partly due to uncertainty about distribution tails.  Strategic planning for these events should focus on scenarios rather than probabilities.

85)  Nicholas Taleb’s Black Swans represent events outside of the previous range of experience.

86)  Truly random events happen in streaks.

87)  There are more ways for things to go wrong than right.  This accounts for the 2nd Law of Thermodynamics (entropy), Murphy’s Law, and Dostoevsky’s aphorism about happy and unhappy families.

88)  It is in the nature of the human brain to sometimes make mistakes.  Thinking is a statistical process, involving thousands of synapses modulating thousands of others.  The process is generally correct, but not always.  –  after Jacob Bronowski, Daniel Kahneman

89)  Today’s geologists will spend the first half of their careers trying to get carbon out of the ground.   We will spend the second half of our careers trying to put it back.

                            - Me, circa 1990

90)  Regarding Climate Change, if we all do a little, we will only do a little.  Large scale solutions are needed.                         - modified from David MacKay

91)  Climate Change solutions need to be efficient (affordable) scalable and timely.  As of today, no such solutions exist.  -  Dr. Charles Hall, SUNY, circa 2009

More than a decade later, we are only a little closer to efficient, scalable solutions, and we are running out of time.

92)  Progress is non-linear, advancing quickly after a breakthrough, but at a diminishing rate.  In fifty years, we went from the Sopwith Camel to the Boeing 747.  Fifty years later, we’re still using the 747.  Maintaining the pace of human progress requires breakthrough ideas.

93)  Risk factors are not all equal.

The risk on an oil prospect is calculated as the product of several component risks – source rock, reservoir rock, seal, trap, and timing.   However, the risks are not of equal scope.  The lack of a source rock condemns a basin; lack of reservoir, seal or poor timing condemns a play; lack of a trap condemns only a prospect.  Risk factors occur in a natural hierarchy and should not be regarded as equal in developing an exploration program.

94)  The main criterion for judging prospects should not be the chance of success on the exploration well, but the probability that if the exploration well is successful, the project will be successful.  Delineation risk should be managed during the prospect generation and selection process.

95)  A good prospect should have five elements.  These elements constrain delineation and development risk.  (AKA Robbins’ Rules.)

        >  A prospect should be simple.

        >  A prospect should be big (enough to be clearly economic if successful, and have a meaningful commercial impact to the company).

        >  A prospect should be seismically visible.

        >  A prospect should have a laterally continuous reservoir.

        >  A prospect should be developed according to a conceptual model.

96)  Every list in a business presentation starts with the author’s personal agenda, followed by several things that everybody knows and ends with the boss’s personal dogma.  (See list above.)

97)  The productivity and wealth of a nation depends on its energy usage and level of integrity.  

Per capita GDP correlates very well with an index weighting energy usage by 2/3 and integrity (from Transparency International) by 1/3.

98)  Your reputation is your most important asset.

                - Steve Robbins (father, b. 1923)

99)  No one can ever take your education away from you.

                   - Steve Robbins (father, b. 1923)

100)  Buying and holding a low-cost stock index is the most effective investing strategy.  This is due to several simple truths: 1) you can’t time the market, 2) a broad portfolio performs best, 3) gains on held stocks compound without tax, and 4) you will minimize management fees.

101)  If you have an investing idea but aren’t sure that you are right, do half of what you originally considered.  This prevents inaction.

102)  My grandfather dropped out of school at fourteen and started a real estate business with his older brother.  He retired at the age of 89.  He said that 75 years in real estate had taught him three things.

1) Every house has cracks.

2) Every house eventually sells.

3) Something is only worth what someone else will pay you for it.

        When I became older, I wondered if he meant this to be an analogy to people.

1) Every person has flaws.

2) There’s a suitable partner for every person.

3) Your value as a person is measured by what you provide to others.

Values

Human values inform the decisions and behavior of individuals and societies.  There are first-order core values, and second-order values which logically follow from core values or the intersection of core values.

The following is a list of my values.

103)  Empathy – Kindness, Compassion, Human Understanding, Care, Generosity

104)  Truth – Honesty, Integrity, Accountability

105)  Equity – Fairness, Justice, Respect, Diversity, Human Dignity, Opportunity, Democracy, Shared Prosperity

106)  Service – Work Ethic, Humility (do the little things),  Productivity (produce more than you consume).

107)  Progress – Science, Exploration, Technology, Physical Understanding, Globalism, Economic Development, Social Development, Peace

108)  Responsibility – Ethics, Family, Community, Care and Provision for Future Generations, Care of Nature for its own sake

109)  Liberty – Individual Freedom, Self-determination

110)  Self-regard – Courage, Reputation, Self-reliance, Challenge, Legacy

--

111)  Values I Reject: Faith, Patriotism, Nationalism,

Creativity

112)  The creative personality is one that looks on the world as fit for change, and on himself as an instrument for change – Jacob Bronowski. 

113)  Creativity is a deliberate process used by clever people to solve problems, or for the pure joy of creation.  There are m9any similarities between technical creativity and artistic creativity.

114)  Creativity begins with deep expertise in a field.

115)  The next step involves reframing the problem or the paradigm.  A good question carries with it the key to its own solution (Law #54).

116)  Creativity often involves inversion of some part of the problem – or asking what would happen if you try exactly the opposite of what you’ve been trying to do.

117)  Visualize the problem from different vantage points, or before and after a process.

118)  Abstract thought (visualization) should alternate with analytical thought (measurement and calculation) in an iterative cycle.

119)  Depending on the problem, multiple solutions may be generated and evaluated before selecting an optimal solution, by some criteria.

120)  The creative work may come as a single inspiration, or a set of incremental innovations.

121)  The final step of any creative process is the realization, through publication, construction or performance of the creative enterprise. – Betty Edwards

Photography

122)  Avoid back-lighting.  Put the subject of the photo in the best light, and focus on the subject.

123)  Try to achieve a range of brightness in the subject.

124)  Underexpose the photo; never overexpose. For landscapes, set the light setting by focusing on the sky.

125)  Check the background for distracting elements.

126)  Check that the horizon is horizontal.

127)  Never put the subject in the middle; follow the rule of thirds.

128)  Direct movement, facing and gaze toward the center of the photo.

129)  In landscapes, put an object in the foreground to create depth in the photo.

130)  Find complimentary colors.

131)  Look for patterns diverging or radiating from a point; look for repeating shapes or patterns at different scales.

Wednesday, November 25, 2020

California Wildfires, Climate Change, and Lisa Murkowski Message #12

 Synopsis

Alaska Senator Lisa Murkowski and James Hubbard, USDA Undersecretary for Natural Resources and the Environment, recently produced a session of the Senator’s podcast, talking about the extraordinary wildfire season in the Western US.  These public servants failed to acknowledge man-made climate change as the ultimate cause of the fire intensity.  Increased fire size and intensity were clearly forecast in the IPCC (Intergovernmental Panel on Climate Change) Impacts report in 1990, thirty years ago.  The causes of increased fire intensity were clearly identified in that report: higher temperatures and drought, leading to low soil moisture, dry plants and deadwood, increased fuel loading and increased lightning strikes.  Every contributing factor identified in the 1990 report has been realized and today’s wildfires are larger and more intense as predicted.  To neglect the explanation for that intensification is irresponsible.  Murkowski and Hubbard failed to inform the public, not only about what happened in 2020, but to warn the public of future risks as CO2 emissions and climate change continue unchecked.

Murkowski’s Message #12

In September of 2020, California was wracked by some of the largest and most destructive wildfires in its history.  Senator Lisa Murkowski, in her role as chair of the Senate Committee on Energy and Natural Resources, met with James Hubbard, USDA Undersecretary for Natural Resources and the Environment, to discuss the crisis.  Senator Murkowski posted audio of the twenty-minute interview as #12 in her series of Murkowski’s Messages, available here:  https://vimeo.com/459453081. 

I listened to the entire discussion. There is practically no mention of climate change, although Murkowski and Hubbard danced around the topic, with Murkowski making a passing reference to “the changing climate”.  However, they quickly brushed that idea aside and focused instead on overstocked fuel conditions in the forests.

Undersecretary Hubbard noted the persistence of abnormal fire conditions in the western states, with Hubbard saying, “…it has been developing for a long time, and it’s certainly going to be with us for a long time….We can expect this kind of fire behavior for some time to come.”  Hubbard also noted the significance of high heat and low humidity in intensifying the fires, and stated “This is unusual, but I think we will see more of it.” 

For her part, Murkowski dismissed the idea of seeking causes for the intense fires.  The Senator said that others were asking, “Why are we seeing so much?  What can be done?  Who is responsible, and who is to blame?”, but these were not questions she wanted to pursue.  In my view, this is deeply flawed.  On the contrary, these are exactly the questions we must answer if we want to avoid even worse wildfires in the future.

Incredibly, this talk by the Senator and the Undersecretary avoided all mention of human-caused climate change, which is the most significant factor in causing the disastrous Western wildfires.  Let me be clear – the dry and hot weather conditions of recent years in the West are due to the accumulation of greenhouse gases in the atmosphere, principally CO2 from human use of fossil fuels.  Hot and dry weather cause low soil moisture, dry plants, and more deadwood.  Low soil moisture causes excess fuel in the forest, and causes fires to burn hotter and faster.  As Undersecretary Hubbard acknowledged, these conditions are strikingly different from the past and will persist a long time.  In fact, these conditions will persist as long as elevated CO2 in the atmosphere persists.  Levels of atmospheric CO2 will inevitably increase in coming decades, worsening the wildfire problem in the West.  We are not likely to return to the CO2 levels and climate conditions of the 20th century for another century or more. 

Forecast of Increased Wildfires, 1990 IPPC Impacts Assessment

For thirty years, we’ve been warned repeatedly that human-caused climate change will result in more destructive wildfires.  Beginning in 1990, each report of the ICPP (Intergovernmental Committee on Climate Change, a UN agency) has warned about the increasing danger of wildfires.  The series of National Climate Assessments produced by the United States have also highlighted the danger. 

The 1990 IPCC Impacts Assessment lays out in explicit detail how and why wildfires are becoming worse, depending on geography.  Temperatures are higher, and some areas are subject to drought; these cause a number of second-order changes that intensify wildfires.  Later IPCC reports provide even more area-specific forecasts.  Here are a few quotes from IPCC 1990 Impact Assessment:

  • "Losses from wild-fire will be increasingly extensive" (Policy-Makers Summary, p. 2)
  • “Fire damage is expected to increase with the susceptibility of forests.  Even if precipitation remains roughly the same, increased temperatures will lead to increased evapotranspiration and thus drier sites.  Warmer drier sites could have a higher incidence of severe fires, especially where stands are in a state of decline because of climatic changes” (p. 2-25).
  • “…blocking high pressure patterns, more lightning strikes and increased fuel loadings are a dangerous combination causing more and larger fires" (p. 2-25).
  • “Wildfire frequency and severity is expected to increase throughout most of the unmanaged lands because of the projected increases in available fuel as primary productivity increases and because of the increased amount of dead fuel accumulating as a result of increased mortality” (p. 3-19).
  • “In those forested areas where there is a decrease in soil moisture, drying of forest fuels will be enhanced, thereby increasing the amount of available fuel”  (p. 3-20).
  • Increased fuel loading resulting from climate change was forecast to cause a three-fold increase in the number of fires greater than 1000 hectares in the Sierra Nevada (p. 3-20). 

Temperature, Precipitation and Fires in California, 2000 – 2020

Dr. Robert Rohde of Berkeley Earth compiled temperature and precipitation data for the California fire season from 1895 to 2020.  The animation of the data can be found on Dr. Rohde’s Twitter page, and is quite striking.  The trend of increasing temperatures and decreasing precipitation across the decades is quite evident in his chart, with 19 of the years from 2000 to 2020 occurring above the midpoint in temperature, and 12 of those 20 years occurring in the hot and dry quadrant of the chart.  The last two decades have also seen the largest deviations from normal conditions of the preceding century. 

Dr. Rohde also posted the ten largest fires and ten most damaging fires in California’s history on the chart, by year.  The year with the farthest excursion from normal temperature and precipitation, 2020, also had the worst fire record.  Other years with bad fire records, 2017 & 2018, were among the years with the farthest excursion from normal.  It’s worth noting that all of the large and destructive fires occurred in the hot and dry quadrant of the chart.

Figure 1.  California temperature and precipitation, 1895 – 2020, with the ten largest fires and ten most damaging fires.  Chart created by Robert Rohde, Berkeley Earth, and used by permission.

Low soil moisture is a consequence of high temperature and low precipitation.  Most of the years since 2000 have been marked by persistent drought conditions in the west.  The USDA published nationwide maps of drought conditions, which have been seasonally persistent in the American West since the year 2000.   National Centers for Environmental Prediction (NCEP), a department of NOAA, publishes maps of soil moisture over the lower 48 states.  Relative soil moisture is shown as a percentile map with respect to historical conditions.  Maps of drought conditions and soil moisture show persistent conditions that predispose the West to high fire activity since the year 2000. 

Figure 2.  Drought conditions, week of September 15, 2020, USDA map.

Figure 3.  Soil Moisture Percentile (relative to history) September, 2020, map from NCEP, NOAA.

Of course, California was not the only place on earth to experience severe fires in recent years.  Dr. Rohde also prepared a similar chart of temperature and precipitation for New South Wales, Australia.  Although Dr. Rohde did not include fire statistics on this chart, the decadal shift in temperature and precipitation is clearly apparent on this chart. 

Figure 4.  New South Wales temperature and precipitation, January – October, 1900 – 2019.   Chart created by Robert Rohde, Berkeley Earth, and used by permission.

In Alaska, Senator Murkowski’s home state, wildfires have also been larger and more damaging.  Lightning initiates most of the wildfires in the state.  It follows that increased thunderstorm activity results in more fires.  The location of the state’s largest recent fires, generally north and east of Fairbanks, corresponds with the highest summer temperatures and increased thunderstorm activity.  This information is documented in communications by Rick Thoman, climatologist with the International Arctic Research Center (IARC), Fairbanks. 

Figure 5.  Alaska Wildfire Acreage, Season Total, 1950 – 2019.  Chart by Rick Thoman, IARC.

Figure 6.  Fairbanks Alaska, Annual Days with Thunder, 1952 – 2020.  Chart by Rick Thoman, IARC.

Conclusion

It’s clear that the scientific forecasts of wildfire intensity in 1990 were correct.  The processes causing more intense wildfires are higher temperatures and lower precipitation, which lead to low soil moisture, dry plants and more deadwood.  Higher temperatures and low precipitation in California and Australia are predictable consequences of human emissions of greenhouse gases, which continue to accumulate in the atmosphere.  The conditions which lead to large, fast-moving and destructive wildfires didn’t “just happen”, and will worsen in coming decades. 

Senator Murkowski and Undersecretary Hubbard failed the public by not discussing the actual causes of the wildfires in their public communications.  Explanations matter, and causes matter.  Senator Murkowski’s questions -- “What can be done?  Who is responsible, and who is to blame?” – are pertinent questions.  Human emissions of CO2 are responsible; consumers of energy are to blame.  And the best thing to do is to reduce emissions of greenhouse gases, significantly and quickly.   

The physical processes of climate change are well-established, proven science.  We’ve known how it works for over 120 years.  We’ve had pretty good estimates for how much temperatures would change, depending on how much CO2 was in the air, for almost as long.  The forecasts of more intense wildfires, made 30 years ago, have been entirely accurate.  At this point, in 2020, it is important for our public leaders to acknowledge man-made climate change as the ultimate cause of intense wildfires, and to give a credible warning that the situation will only get worse as temperatures continue to rise.  Senator Murkowkski and Undersecretary Hubbard have done the public a disservice by neglecting to address the cause of 2020’s extraordinary fire season, and to give a warning for the future.  It’s time for them to address the public truthfully.

References

Murkowski's Message #12    https://vimeo.com/459453081

Arrhenius, 1896, On the Influence of Carbonic Acid in the Air upon the Temperature on the Ground  https://www.rsc.org/images/Arrhenius1896_tcm18-173546.pdf

Arrhenius, 1906, The Probable Cause of Climate Fluctuations http://www.friendsofscience.org/assets/documents/Arrhenius%201906,%20final.pdf

Climate Change, The IPCC Impacts Assessment, 1990  https://www.ipcc.ch/site/assets/uploads/2018/03/ipcc_far_wg_II_full_report.pdf

Forest Fuels   

California Department of Forestry and Fire Protection  https://californiasaf.org/policy/forest-fuels-management/

University of California Cooperative Extension  https://ucanr.edu/sites/fire/Prepare/Treatment/

California chapter of the Society of American Foresters   https://californiasaf.org/policy/forest-fuels-management/

Soil Moisture maps

https://www.cpc.ncep.noaa.gov/products/Soilmst_Monitoring/US/US_Soil-Moisture-Monthly.php

https://www.cpc.ncep.noaa.gov/products/Soilmst_Monitoring/US/Soilmst/Soilmst.shtml#

Drought Maps

https://droughtmonitor.unl.edu/Maps/MapArchive.aspx

Australia's Climate in 2019  

http://www.bom.gov.au/climate/current/annual/aus/

Australia’s climate in 2019

  • Australia's warmest year on record, with the annual national mean temperature 1.52 °C above average
  • Both mean annual maximum and minimum temperatures above average for all States and the Northern Territory
  • Annual national mean maximum temperature warmest on record (2.09 °C above average)
  • Widespread warmth throughout the year; January, February, March, April, July, October, and December all amongst the ten warmest on record for Australian mean temperature for their respective months
  • Significant heatwaves in January and in December
  • Australia's driest year on record
  • Nationally-averaged rainfall 40% below average for the year at 277.6 mm
  • Rainfall below average for most of Australia
  • Rainfall above average for parts of Queensland's northwest and northern tropics
  • Much of Australia affected by drought, which was especially severe in New South Wales and southern Queensland
  • Widespread severe fire weather throughout the year; national annual accumulated Forest Fire Danger Index highest since 1950, when national records began

Saturday, December 21, 2019

Understanding the Source of Rising Atmospheric CO2


For the last time, increasing atmospheric CO2 is coming from fossil fuels, and not from volcanoes.

The concentration of CO2 in the atmosphere is rising rapidly.  Before widespread burning of coal, circa 1750, atmospheric CO2 was about 280 parts per million (ppm).  By 1955, global CO2 concentration had risen to 314 ppm.  Average global CO2 levels are now about 412 ppm, and are still rising at about 3 ppm per year. 

Industrial processes are able to change the composition of the earth’s atmosphere because there really isn’t very much atmosphere, and there isn’t very much CO2.  The atmosphere thins rapidly with altitude, so that about half of the atmosphere is less than 3 miles above the earth, and breathable atmosphere extends only about 6 miles above the earth.  Further, there isn’t very much CO2 in the atmosphere – about 400 ppm, or 0.04%.  Nevertheless, that small amount of CO2 is very effective at blocking thermal infrared radiation, which is why changing the CO2 concentration of the atmosphere has already had a significant impact on global climate. 

Figure 1.  There isn’t very much atmosphere, and there really isn't very much CO2.  The pie-slice of CO2 in the second figure is exaggerated three-fold for visibility.

A common myth that circulates on social media is that rising CO2 in the atmosphere is coming from volcanoes.   It isn't.  I already wrote one blog post about the origin of atmospheric CO2.  (https://dougrobbins.blogspot.com/2017/06/volcanic-co2-emissions.html). 

This blog post will present additional evidence that rising CO2 is of human origin.  The evidence is:
  • Declining oxygen concentration of the atmosphere
  • The quantity of missing oxygen
  • The location of declining oxygen concentration by hemisphere
  • Volumetric data for fossil fuel emissions, deforestation, and volcanism, compared to volumes of CO2 appearing in the atmosphere
  • The location of rising CO2 by hemisphere
  • Changing carbon isotopic composition of the atmosphere
  • The location of the declining carbon isotope measure (del C13) by hemisphere
  • The steady rise of atmospheric CO2, whereas volcanic eruptions are intermittent (although slow emissions from non-eruptive events, mid-ocean ridges and rifts also occur). 
Atmospheric CO2 is now also monitored by two orbiting carbon observatories (OCO), which directly measure CO2 concentrations in the atmosphere and connect rising atmospheric CO2 with points of origin.

The myth that volcanoes are responsible for human-caused atmospheric disruption has been propagated since the 1990s.  The book “Merchants of Doubt” provides a history of claims that volcanoes were responsible for destruction of stratospheric ozone, or for acid rain in the US and Canada.  Those claims were thoroughly debunked long ago.  Nevertheless, articles attributing rising CO2 to volcanoes still appear on climate-change denying websites, (e.g. James Edward Kamis’ 2018 post on ClimateChangeDispatch).

Let’s look at the evidence.

Fossil-Fuel Combustion
When fossil fuels are burned, atmospheric oxygen is converted to CO2.  Consequently, the oxygen concentration in the atmosphere falls.  If we quantify oxygen depletion in the atmosphere, we find that it validates the volumes of fossil fuel consumption reported by inventory methods (BP Statistical Review, CDIAC, EIA, etc.).  The volumes of CO2 determined by either method are approximately twice what is necessary to account for the observed rise in atmospheric CO2.  The remaining CO2 is dispersed into CO2 reservoirs in the oceans and biosphere.  A full accounting of the CO2 flows on earth can be found in the Global Carbon Project or Berkeley Earth websites. 

Simply stated, the depletion of atmospheric oxygen quantifies CO2 emissions from fossil fuels.  This volume of CO2 emssions more than accounts for the rise in atmospheric CO2.  There isn’t any room for a significant contribution from volcanoes without somehow getting rid of the CO2 from the combustion of fossil fuels in some as-of-yet unidentified carbon sink (which is unlikely to exist). 

Depletion of Atmospheric Oxygen
The amount of oxygen in the atmosphere is falling (although not enough to cause trouble for breathing).   Atmospheric oxygen is falling because oxygen is consumed by burning fossil fuels.  This would not occur if the source of rising CO2 was from volcanoes (Figure 2).  As seen in the bulk CO2 and Del C13 charts, there is a strong seasonal signal in the concentration of atmospheric oxygen, related to the growing season in each hemisphere.  The amplitude of the seasonal cycle is somewhat stronger in the Northern Hemisphere, due to the preponderance of temperate land-mass and agriculture. 
Figure 2.  The concentration of atmospheric oxygen is falling, due to combustion of fossil fuels.  The Per Meg (del O2/N2) can be roughly converted to ppm by multiplying by 0.2095, the fractional concentration of oxygen in the atmosphere.  A discussion of the Per Meg (del O2/N2) measure can be found on the Scripps Institute CO2 website FAQs.  The loss of 700 ppm of oxygen is a relatively small change because of the greater abundance of oxygen in the atmosphere as compared to CO2.  The percentage of oxygen in the atmosphere is about 20.95%; the percentage of CO2 in the atmosphere is about 0.04%.

Oxygen Depletion by Hemisphere
Falling oxygen concentrations in the Northern Hemisphere lead falling oxygen in the Southern Hemisphere (Figure 3).  This is because 90% of fossil fuels are being burned in the Northern Hemisphere, consuming oxygen in the Northern Hemisphere.  Atmospheric mixing works to equilibrate oxygen concentrations, but continuing combustion of fossil fuels in the Northern Hemisphere keeps oxygen lower than in the Southern Hemisphere.

Figure 3.  Atmospheric oxygen recorded by Scripps Institute network of atmospheric observatories.   The seasonal cycle at each station was filtered with a 12-month rolling average.  The Northern Hemisphere leads the Southern Hemisphere in falling oxygen.

Oxygen – Carbon Stoichiometry
The number of molecules of oxygen disappearing from the atmosphere is a very close match to the number of carbon atoms burned in fossil fuels and deforestation (Figure 4).  There is a quantitative match, showing that for each atom of carbon burned, one molecule of oxygen disappears from the atmosphere, as C + 02 -> CO2.  The depletion of atmospheric oxygen, in stochiometric balance with human carbon combustion, validates the volume of CO2 released into the atmosphere by burning fossil fuels.  
Figure 4.  Moles of carbon burned by fossil fuels and deforestation annually, compared to atmospheric oxygen depletion in moles.   The close match confirms that volumes of CO2 released from fossil fuels and deforestation are responsible for rising atmospheric CO2.  
Moles of oxygen depletion can be calculated by converting “per meg” to ppm (oxygen/atmosphere) and assuming an initial volume of the total atmosphere of 1.81E+20 moles (various Internet sources).  Notes on the calculation are given in the Appendix, following References.

Volumetric Evidence
CO2 emissions from gas, oil, coal, cement, flaring, and deforestation are now about 40 gt per year, and forecast to go higher.   Estimates and measurements of volcanic CO2 emissions are far smaller than known volumes of CO2 from fossil fuels and deforestation (Figure 5).  Estimated volumes of volcanic CO2 include deep carbon emissions, and passive emissions from continental rifts and mid-ocean ridges.  Volcanic CO2 emissions are only about 1.8% of human CO2 emissions by volume.

Figure 5.  Annual Human CO2 Emissions by type and Volcanic CO2 Emissions, with EIA forecast to 2040.  Estimates of CO2 emissions from volcanic activity have been revised significantly higher since the 1990s, as CO2 emissions from deep volcanic source, continental rifts and mid-ocean ridges have been recognized and quantified.  Still, volcanic CO2 emissions are now estimated at about 700 million tonnes, compared to about 40 gigatonnes of CO2 from fossil fuels and deforestation.

Fraction of CO2 Emissions Which Remain in the Atmosphere
Only about 44% of human CO2 emissions remain in the atmosphere; the rest of the CO2 is absorbed by the oceans or taken up by plants.  Human CO2 emissions are more than twice what is necessary to account for rising atmospheric CO2.  Since volcanic CO2 emissions represent only 1.8% of human CO2 emissions, it is impossible for volcanoes to account for the large volume of CO2 now appearing in the atmosphere.  (Figure 6). 

Figure 6.  If all human CO2 emissions remained in the atmosphere, atmospheric CO2 concentrations would rise about twice as fast as what is observed (red line).  Actual average global CO2 is rising at a rate of about 44% of cumulative human CO2 emissions.  If only volcanic CO2 was entering the atmosphere, atmospheric CO2 would rise only negligibly, offset by the removal of carbon by natural processes.

Difference in CO2 between Northern and Southern Hemispheres, and
Comparison to Net CO2 Emissions from the Northern Hemisphere
About 90% of humans live in the northern hemisphere, and 90% of human CO2 emissions originate in the northern hemisphere.  Atmospheric CO2 concentrations in the northern hemisphere are consistently higher than CO2 concentrations in the southern hemisphere.   The amount of the difference is very close to the net CO2 emissions from fossil fuels in the northern hemisphere (Figure 7).  The close correspondence of net Northern Hemisphere CO2 emissions and the difference between Northern and Southern CO2 concentration is partly a coincidence between the mixing rate between the hemispheres and the reporting period for CO2 emissions.  However, the consistent fit is a clear proof that fossil fuel emissions in the Northern Hemisphere are principally responsible for rising CO2.  The largest volcanic eruptions of the past 60 years have been in the Southern Hemisphere, but these have made no impact on the record of atmospheric CO2.
Figure 7.  Northern and Southern Hemisphere CO2 concentrations, and net fossil-fuel emissions from the Northern Hemisphere.  Major volcanic eruptions, such as Mt. Pinatubo and Mt. Hunter in the Southern Hemisphere in 1991, are not observed as a difference in CO2 observations between the hemispheres. 

Carbon Isotope Ratios in Atmospheric CO2
Natural carbon mostly occurs in two isotopes: C12 and C13.  Plants and all fossil fuels (which derive from plants) are enriched in C12 by biological processes, giving fossil fuel emissions and deforestation a “lighter” isotopic signature (more C12) than the atmosphere.  The measure of carbon isotopic ratios is d C13/C12, typically called “del C13”.  Samples which are relatively enriched in “light” C12 have a negative del C13, while samples that are enriched in “heavy” C13 have a positive del C13.  A technical definition of del C13 is given at the bottom of the article, below the references.

In the 1950s, the atmosphere had a del C13 value of about -7.5, reflecting a higher concentration of C12 than the oceans, which has a del C13 of about zero.  As mentioned above, fossil fuels are enriched in C12 with typical values in the range of -20 to -30.   Biogenic natural gas has been fractionated twice, and may have del C13 values ranging from -40 to -70.  Volcanic emissions have a heavier isotopic signature than the atmosphere, with a del C13 value of about -1 to -4.  

The isotopic composition of the atmosphere is steadily becoming lighter as CO2 concentrations rise.  This is only possible if the additional CO2 is from a source isotopically lighter than the atmosphere, not heavier.  Thus, fossil fuels, and not volcanoes or the oceans, are the source of rising CO2 (Figure 8).
Figure 8.  The Del C13 Carbon Isotopic Record of Atmospheric CO2, recorded by the Scripps Institute.  The record is marked by a strong seasonal cycle in the Northern Hemisphere.  During the Northern Hemisphere growing season C12 is preferentially taken out of the atmosphere by plants, and released back to the atmosphere in winter causing the seasonal cycle in the air.  Overall, the Del C13 index has fallen from -7.5 to -8.5 since 1977, showing an increasing prevalence of light C12 (characteristic of fossil fuels and deforestation) in the atmosphere.

After filtering the seasonal cycle, we see that the Northern Hemisphere leads the Southern Hemisphere in falling Del C13 isotope ratio (Figure 10).  This is because 90% of fossil fuel emissions occur in the Northern Hemisphere. The remaining wavy signal in the Del C13 record correlates to El Nino cycles (Figure 9), with a rapidly falling Del C13 ratio during El Nino events, and a slightly rising Del C13 ratio during La Nina events.  It is unclear whether the El Nino signal in the data is due to fractionation between atmosphere and ocean, changes in the uptake of carbon in the ocean, or related climate events. 
Figure 9.   The Del C13 carbon isotope record in atmospheric CO2, from Scripps Institute atmospheric observatories; the seasonal cycle was filtered with a 12-month rolling average.  Broadly, the Northern Hemisphere leads the Southern Hemisphere in falling Del C13, because 90% of CO2 emissions from fossil fuels occur in the Northern Hemisphere.  The residual long-wavelength signal relates to the El Nino/La Nina cycle. [See an earlier post:
https://dougrobbins.blogspot.com/2013/11/carbon-isotopes-in-atmosphere-part-ii.html ]

Rate of Increase in Global Atmospheric CO2
Atmospheric CO2 is steadily rising around the globe.  Volcanic eruptions are intermittent; the largest eruption (Mt. Pinatubo) and the third-largest eruption (Mt. Hudson) of the past century both occurred in 1991, but there is no perceptible change in the rate of rising atmospheric CO2 (Figure 10).  Likewise, other large volcanic eruptions produced no perceptible impact over the period of detailed CO2 observations [Mount Agung (1963), Mt. St. Helens (1980), El Chichon (1982). Puyehue-Cordón Caulle (2011)].  Slow, *quiet*, emissions of CO2 also occur from non-eruptive events, mid-ocean ridges and onshore rifts, but these have been well quantified over the past 20 years, and do not contribute significant volumes of CO2 to the atmosphere.
Figure 10. Global atmospheric CO2.   This is my version of the Keeling Curve.  Data is from the Scripps Institute network of atmospheric observatories.  Cool colors indicate stations in the Northern Hemisphere. Warm colors show stations in the Southern Hemisphere. Atmospheric CO2 falls in the Northern Hemisphere summer, as carbon is taken up by plants, and rises in winter as the plants decay.  There is a strong seasonal cycle dominated by the Northern Hemisphere due to predominant location of temperate landmass and agriculture in the Northern Hemisphere.  Apart from the seasonal cycle, CO2 has risen steadily from about 314 ppm in 1955 to about 412 ppm today.

Orbiting Carbon Observatories and NASA CO2 Modeling
Two new NASA satellites, OCO2 & OCO3, now provide worldwide continuous CO2 monitoring.  Data gathered by these satellites will provide a detailed identification of the specific sources of CO2 across the entire globe. 

NASA also prepared a supercomputer simulation of atmospheric CO2, based on ground-based and aerial CO2 observations.  A video of the simulation can be seen on YouTube:
The simulation highlights major CO2 sources, in the eastern US, eastern China, industrial centers of central & eastern Europe, oilfields of western Siberia, and wildfires in the Amazon rainforests (Figures 11A and 11B).

Figures 11A and 11B.  Atmospheric CO2 Concentrations from NASA supercomputer simulations for the year 2006.  The location of CO2 sources is apparent from cities, industrial centers, and wildfires.

Conclusion
Rising CO2 concentrations are unquestionably from human sources, as a result of combustion of fossil fuels and deforestation.  There is volumetric, temporal, isotopic, geographic, stoichiometric evidence supporting human sources of rising atmospheric CO2.  There is no evidence that volcanoes make a significant contribution to rising CO2.

References:
Previous Posts on Volcanic and Atmospheric CO2

Posts on Twitter on Volcanic CO2

External References:
Scripps Institute CO2 Home
Scripps Institute O2 Program

Boden, et al, 2013, Global and National Fossil-fuel CO2 Emissions, in Global Carbon Atlas
http://www.globalcarbonatlas.org/en/content/fossil-fuel-emissions
http://www.globalcarbonatlas.org/docs/Public_Presentation_of_the_GCA_Paris_EN.pdf

Burton et al, 2013,  Deep Carbon Emissions from Volcanoes
Discussion of CO2 flux from subaerial volcanic eruptions on page 332.
Total CO2 flux from volcanic sources:  637 mT per year, p. 341, table 6.
The eruption of Mt. Pinatubo in 1991 was the largest volcanic eruption since 1912.   That eruption produced ~50 Mt of CO2 (Gerlach et al. 2011).  Individual eruptions are dwarfed by the time-averaged continuous CO2 emissions from global volcanism.  The eruption of Mt. Pinatubo was equivalent to only 5 weeks of global subaerial volcanic emissions. 
The average volume of eruptive CO2 emissions over the past 300 years was only 0.1 cubic kilometers, which suggests an annual rate of about 1 million tonnes of CO2 annually (Crisp, 1984, cited in Burton).
CO2 consumption from continental silicate weathering was 515 Mt/yr, (Gaillardet et al., 1999, cited in Burton).
Metamorphism accounts for the release of about 300 million tonnes of CO2 annually.  (Mörner and Etiope, 2002, Carbon degassing from the lithosphere. Global Planet Change 33:185-203, cited in Burton). 

Lee et al, 2016, Massive and prolonged deep carbon emissions associated with continental rifting,  Nature Geoscience Letters, Jan.18, 2016. 
Paper accounts for additional CO2 emissions from East African Rift, potentially bringing natural world CO2 emissions to 708 mT, an increase of 11% from previous estimates.

Houghton, R.A. 2008. Carbon Flux to the Atmosphere from Land-Use Changes: 1850-2005. In TRENDS: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A.

Marland, G., T.A. Boden, and R.J. Andres. 2008. Global, Regional, and National Fossil Fuel CO2 Emissions. In Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A.

Erik Klemetti, 2015, Volcanic versus Anthropogenic Carbon Dioxide: An Addendum, WIRED website.

Pre-industrial atmospheric del C13 was about -6.5, and declined following industrialization, in correlation with rising atmospheric CO2.

Representative del C13 values from volcanism:
Del C13 :  -3.2
Del C13: -4.9 to -6.3
Del C13: Currently  -0.9 to -1.4; 1970s and 1980s ~ -4
Del C13: -6 to -10.  N.B.: These are samples of soil gases in a rift zone with known petroleum generation, and may be contaminated by thermogenic or biogenic CO2 deriving from petroleum sources.  
Faure, 1984, Principles of Isotope Geochemistry
Del C13: -2 to -6. 

Volcanoes and CO2
A good discussion of former and current estimates of CO2 emissions from volcanoes and fossil fuels.  Also, a good recap of errors made by certain commentators in creating and propagating the volcanic CO2 myth. 

Naomi Oreskes and Erik Conway, 2010, Merchants of Doubt.
A deeply researched book about right-wing scientists, funded by industry, working outside of their fields of expertise, tried to throw doubt on science that might result in regulations in the interest of public health or environmental protection.  The scientists involved were generally retired, had worked in military science and were given compensation or recognition in return for their efforts.  Among the false narratives they created was the idea that volcanoes were responsible for chlorine damage to stratospheric ozone, and that volcanoes were responsible for acid rain in the US and Canada.  Neither idea is correct.  The idea of blaming volcanoes for man-made atmospheric disruption has now been extended to CO2 and climate change.

Which emits more carbon dioxide: volcanoes or human activities?  Climate.gov.

The following are examples of deliberately misleading media articles about atmospheric CO2.
Volcano eruption WARNING: Intense volcanic CO2 activity 'drives GLOBAL EXTINCTION'
Article omits mention of fossil fuels entirely.

J.E. Kamis, 2018, Discovery Of Massive Volcanic CO2 Emissions Puts Damper On Global Warming Theory
This article contains false claims.  Notably, the article claims that:
“Natural volcanic and man-made CO2 emissions have the exact same and very distinctive carbon isotopic fingerprint.  It is therefore scientifically impossible to distinguish the difference between volcanic CO2 and human-induced CO2 from the burning of fossil fuels (see here).”
The reference provided (https://skepticalscience.com/anthrocarbon-brief.html) directly contradicts the claim!  “In fact the global C13/C12 ratio has declined, which is very strong evidence the source of the CO2 increase has was C12 enriched, ie, derived from photosynthesis.  Therefore it is very strong evidence that it comes from the biosphere or fossil fuels, rather than from volcanoes or oceanic outgassing.”

Appendix
Stoichiometry Calculations
Annual fossil fuel emissions are reported in tonnes of CO2 by CDIAC, the BP Annual Statistical Review of World Energy, and the EIA.  One tonnes of CO2 (1000 kg) contains 22,722 moles of CO2. 

Calculation Notes for atmosphere stoichiometry.  The Scripps pages on units and FAQs are helpful in understanding the use of the “per meg” unit, and conversion to ppm. 

“Per meg” units of oxygen reported by Scripps can be converted to ppm (oxygen/atmosphere) over small ranges by multiplying by 20.95%, the current oxygen fraction in air.  Parts per million (ppm) of oxygen can then be converted to moles by multiplying by the number of moles in the atmosphere (1.81E+20), from various Internet sources.  https://www.theweatherprediction.com/habyhints3/976/

A Few Words about CO2 Carbon Isotopes
There are two stable isotopes of carbon, C13 and C12.  C12 is the more abundant isotope; the natural ratio of C12 to C13 is about 99 to 1.  The standard measure of carbon isotopes compares the C12/C13 isotope ratio of the sample in question to the C13/C12 ratio of a standard limestone, according to the expression:

d C13/C12 = ((C13/C12 sample/C13/C12 standard) – 1)*1000.

This expression, commonly termed “del 13”, amplifies small but meaningful differences in the isotopes, which are diagnostic of certain processes and occurrences of carbon.  The standard is a uniform Cretaceous limestone with a d 13 value defined as zero.   Positive values indicate a heavier composition, i.e., a greater concentration of C13 than the standard.  Negative values indicate a lighter composition, i.e., a smaller concentration of C13 than the standard.

Plants fractionate carbon, favoring the lighter isotope C12.  Anything derived from plants, including oil, gas, and coal (and algae, animals and people) carries a light (negative) d C13/C12 signature.  Limestone carries a d C13/C12 ratio near zero.  The atmosphere, in 1977, had a d C13/C12 ratio of about -7.5; it is currently about -8.3, reflecting the influence of fossil fuels.  Oceans have a slightly positive d C13/C12 ratio of dissolved inorganic carbon, although Northern Hemisphere waters show a negative ratio due to the greater use of fossil fuels in the Northern Hemisphere.  Fossil fuel CO2 emissions and CO2 emissions from deforestation carry a very light d C13/C12, often in the range of -25 to -28 (although biogenic natural gas, which is fractionated twice, can have del 13 value in the range of -40 to -70).  The distinctive isotopic signature of CO2 from fossil fuels and deforestation is useful in tracking the movement of carbon through the atmosphere and oceans.