Saturday, July 16, 2011

Occam’s Razor and Global Climate Change

William of Occam
            Occam’s Razor is an epistemology  based on the philosophies of William of Ockham. Occam was a friar and a philosopher from Oakham, a small village in Surrey, England. William is best known for his philosophic problem-solving style, which has come to be known as Occam’s razor. This methodology applies when choosing between competing ideas or theories that explain a phenomenon with similar explanatory power.  In such cases, William's philosophy states the theory with the fewest assumptions is the more reliable, and favorable, theory.

            This methodology is logical because it favors facts a day parchment over assumptions and convolution.  Thus aids in weeding out possible confirmation bias and unfounded postulations. If one finds themselves making a lot of assumptions to justify a belief, it is an indicator their belief is unscientific, and illogical. This does not mean it is wrong, but only that it is less reliable in the scientific world view.

            Children tend to see the world through black and white goggles, often seeing good and evil, right and wrong, truth and falsehood, as cut-and-dry concepts. Children are seemingly constrained by sharp deep lines that separate our perceptions of reality and truth. As children grow older, these lines often blur and the previous sharp contrast of black and white explode into a million shades of grey; rarely, if ever, do we deal with absolutes.

Flat Earth Society Map
            As I perceive the debate on global climate change there are big questions that need to be answered. How do we know what to believe? What is black, and what is white? Will we ever come to unanimity in belief? This is very unlikely to happen on any subject. Today there are those who dispute just about any scientific theory. The Flat Earth Society is a good example of this. The Flat Earth Society believes that the earth is not a globe but rather a flat circular disc. This movement has intellectual and educated people in it. I use this example because it helps demonstrate that even well established and seemingly logical ideas have critics and skeptics.

            We do not and cannot know with full certainty that anthropogenic climate change is occurring nor can we know for certain that the world is spherical. As we learn from the reasoning of French philosopher Rene Descartes, if we take skepticism to the extreme we cannot believe anything in this world except that we ourselves think and are thus existent. When it comes down to it, all that we believe can be doubted.

Greg Craven
             Thus as we examine the information and ideas in relation to anthropogenic climate change, we should not require absolute proof or seek for an uncontended consensus but rather we should adopt the mantra of Greg Craven that,
 “[We] don’t need to determine who is right to make a decent bet.”

             This situation provides a need for critical thinking and analysis skills such as the principle of Occam’s razor. I wish to apply Occam’s razor to the driving question in the global climate debate discussion: Why is the earth getting warmer? I will attempt to briefly examine the most popular claims from both sides of the discussion. Then, both sides will be examined with the question, “Which side assumes less?”

            We will start by explaining the Warmers’ position. The position is fairly universal among Warmers and the default position in the scientific community.

            Through direct temperature measurements from the mid 1860’s until 2000, there has been a rise in the global average temperature by 0.8 degrees Celsius (1.44 Fahrenheit). These recent measurements correlate well, in most regards, with that of proxy measurements used to determine past temperatures.

            This rise in temperature is attributed to the increase in concentration of Greenhouse gasses in the atmosphere. Greenhouse gasses are gasses which can absorb and radiate infrared waves. The most efficacious greenhouse gasses are water vapor (60 – 70 % of total greenhouse gas effects), carbon dioxide (9 – 26 %), methane (4-9%), and ozone (3-7%). These greenhouse gasses absorb and radiate infrared light coming from the earth back towards the earth causing a blanket-like effect. This causes the earth to retain more of the heat received from the sun and thus raises the temperature of the earth. The greenhouse effect is the Warmers’ explanation why the earth is getting warmer.

            Skeptics, here defined by myself for the purpose of this article, are those who disbelieve anthropogenic climate change. They have two main explanations as to why the globe is apparently warming:

Fred Singer
            The first response is simply that the world is not warming. Skeptics claim that the temperature records are subject to large errors and that the coverage for direct measurements has been patchy therefore producing inaccurate global temperatures. They cite the urban heat island effect as a cause. Fred Singer, a prominent skeptic, stated that it is difficult to believe anthropogenic climate change when some predictions of climate models for the future have been inaccurate:
“…until the observations and the models agree, or until one or the other is resolved, it's very difficult…to believe in the predictive power of the current models.”

            I believe that Occam’s razor would dictate that we favor the Warmers’ position. The skeptics’ position an acceptable theory, but it relies on assumed uncertain and unscientifically-founded errors. It does not seem to provide better alternative information or data to explain the apparent increase in temperature.

           While their claim of inaccuracy of direct measurements was generally valid, the scientists have conducted studies and have made corrections in relation to these criticisms to the best scientific knowledge we have. However, the results still indicate an increasing global temperature which cannot be explained by the heat island effect; further NASA studies have examined the heat island effect and found that is it not a significant factor in the direct measurements.

           As for the supposed failure in models, models are not perfect and cannot account for all the potential changes in the climate due to variations. It cannot completely project future conditions as the variables are not all known nor are models primarily intended to project future conditions thus errors are inevitable in the scientific process and more more often call for refining rather than abandonment.

            An additional issue when claiming the globe is not warming is the fact that proxy measurements generally agree with the direct measurements. Further we can see ice melting at an increased rate. Ice that has persisted for hundreds of years is melting, and thus sea levels are rising. These indicate an overall change in temperature of the globe.

            If we look at the carbon dioxide concentrations in regards to global temperature throughout history we see that there is a heavy correlation. We see this on our earth through direct and proxy measurements. We also see it in planets such as Venus which has a higher concentration of greenhouse gasses. Although Venus is much further from the sun than Mercury, it is much warmer. It takes more of a leap of faith to say that the apparent correlation of carbon concentrations, temperature, direct measurements, and proxy measurements is result from anomalies and inaccuracies than it is to say that the measurements are generally accurate. There seems to be more assumptions made by the Skeptics in this view than by the Warmers.

Khabibullo Abdusamatov
            A second skeptical view is that global warming is occurring but that it is natural and not caused by humans. Skeptic Khabibullo Abdusamatov claims:
“Global warming results not from the emission of greenhouse gases into the atmosphere, but from an unusually high level of solar radiation and a lengthy – almost throughout the last century – growth in its intensity.”
Tim Patterson

            Likewise, Tim Patterson testified to the Commons Committee on Environment and Sustainable Development stating,
“There is no meaningful correlation between CO2 levels and Earth's temperature over this [geologic] time frame. In fact, when CO2 levels were over ten times higher than they are now, about 450 million years ago, the planet was in the depths of the absolute coldest period in the last half billion years...how could anyone still believe that the recent relatively small increase in CO2 levels would be the major cause of the past century's modest warming?”
            It is pointed out frequently that the earth goes through cycles; it has been hotter, and it has been cooler. As is shown by Patterson, there have been periods in history where there have been high greenhouse gasses concentrations in the air while having lower temperatures. Recently, many skeptics have pointed out that the earth has not significantly risen in temperature since 2002 despite the fact that CO2 emissions have continued to increase.

            Warmers would respond that while the models do not have 100% accuracy they have been shown to be very accurate over long term patterns. Short term predictions are very difficult to accurately make because of so many unknown variables. Anomalies in the pattern have been and are to be expected. However, as we look at the long-term results that the models predicted, they match current records.

            Due to the apparent accuracy of models we currently have I believe it would be more of an assumption to believe that the correlation between carbon dioxide and global temperature is a coincidence than to believe that the discrepancies in the short-term predictions are due to natural short-term variations and anomalies that were unaccounted for. I believe that Occam’s razor would again support the warmers’ position.
CO2 Hockey Stick Graph

            The last issue I would like to examine with Occam’s razor is the issue of scientific consensus. Why do most climatologists believe in anthropogenic climate change? Is it because they do not understand? Do they purposefully tout information they believe it untrue? Or is it that it makes sense to them, and thus the majority of people believe in it? I would say the simplest, less assuming answer would be the latter. Let us assume that the scientists trained in this area of expertise are honestly working their best to further humanity.

            Occam’s razor does not necessitate truth, but it does help make decisions for individuals. It has 

helped me to accept the tenants of anthropogenic climate change as I feel that it is less assuming than climate skepticism. I do not feel that I have determined what is right or wrong, but I do feel that with the information I have I can make a decent bet.

Works Cited

"BBC News - The Arguments Made by Climate Change Sceptics." BBC News - Home. Web. 14 July 2011. .

"Changes in Arctic Land Ice and Impacts on Sea Level - Barry." NOAA Arctic Theme Page - A Comprehensive Arctic Resource. Web. 14 July 2011. .

Craven, Greg. What's the Worst That Could Happen?: a Rational Response to the Climate Change Debate. New York: Perigee, 2009. Print.

Descartes, René, Elizabeth Sanderson Haldane, David Eugene Smith, William Hale White, René Descartes, René Descartes, René Descartes, and Benedictus De Spinoza. Rules for the Direction of the Mind. Discourse on the Method. Chicago: Encyclopaedia Britannica, 1955. Print.

"Does CO2 Always Correlate with Temperature (and If Not, Why Not?)." Global Warming and Climate Change Skepticism Examined. Web. 15 July 2011. .

"ESA Portal - Greenhouse Effects... Also on Other Planets." ESA Communications Portal. Web. 15 July 2011. .

The Flat Earth Society. Web. 14 July 2011. .

"Global Warming." Global Warming. Web. 14 July 2011. .

Gray, Vincent. The Greenhouse Delusion: a Critique of "climate Change 2001" Brentwood: Multi-Science, 2002. Print.

Hansen, J., R. Ruedy, M. Sato, M. Imhoff, W. Lawrence, D. Easterling, T. Peterson, and T. Karl. "A Closer Look at United States and Global Surface Temperature Change." Journal of Geophysical Research 106.D20 (2001): 23947-3963. Print.

Harris, Tom. "Global Warming, Scientists, Al Gore Climate Change." Canada Free Press: Online Conservative Newspaper, News, Politics, Editorials. Web. 15 July 2011. .

Leff, Gordon. William of Ockham: the Metamorphosis of Scholastic Discourse. Manchester: Manchester UP, 1975. Print.

Media Construction of Global Warming. Ithaca, NY: Project Look Sharp, 2010. Print.

"Russian Academic Says CO2 Not to Blame for Global Warming." Russian Information Agency. Web. 14 July 2011.

"Temperature Change and Carbon Dioxide Change." National Oceanic and Atmospheric Administration. Web. 15 July 2011. ."What's up with the Weather: the Debate: Dr. S. Fred Singer." PBS: Public Broadcasting Service. Web. 14 July 2011.

Saturday, June 25, 2011

Water, ESNO, and Natural Climate Change

Introduction
          As a child I was often in trouble with my parents. The offenses ranged from not telling them where I had gone to getting into fights with my older brother Timothy. Going through these challenges and experimenting in my youth taught me many lessons about life. I am often amazed that the simple lessons I learned as a child apply in new circumstances today. One lesson which I never knew was going to help me later happened while in the bathtub. As I imagine is common with most children, I didn’t want to take baths. If I had to take a bath I thoroughly enjoyed them; I would make fantastic tidal waves by pushing my body back and forth in the bathtub which would have the adverse effect of creating a small lake on the tile floor of our bathroom. My parents were not too impressed with my fun, but perhaps they would not make me take another bath in the future. Through observing the movement of water and the effect that I had on it, it helped me better understand how such things as thermohaline circulation and water currents work.

Water and the World
          Water covers roughly 70.9% of the world’s surface; it is essential for all known forms of life. According to The World Almanac and Book of Facts Americans use on average 123 gallons of fresh water each day; if this held true as a national average than the entirety of the world uses 852,390,000,000 (852 billion) gallons of water daily. Water provides the means to clean ourselves, prepare our food, and it nurtures wildlife which we in turn eat. However, many people are unaware or perhaps uninterested that water plays a large part in Global weather and temperature. Water affects the climate and weather in several ways: it is the source of precipitation, it absorbs carbon dioxide, while water vapors are in the air it acts as a greenhouse gas, and water creates cloud cover which provides shade and can reflect and radiate away energy. Water can also affect the climate through thermohaline circulation, also known as the ocean conveyer belt. This affects both local temperatures through the transfer of water and the global climate. Water also takes a lot of energy to change temperature and as such it absorbs much of the sun’s heat. Otherwise, it would have had to have been absorbed by land mass which heats up much easier than water. Another way that water affects us is through cycles such as the El Nino of La Nina.

The El-Nino Southern Oscillation (ENSO)

          El Nino and La Nina or the El-Nino Southern Oscillation (ENSO) is a quasiperiodic climate pattern occurring across the Pacific Ocean. It is a pattern that affects weather around the world. In this pattern there are two oscillating phases: El Nino, which is characterized by warmer weather, and La Nina, which is characterized by cooler weather. According to the National Oceanic and Atmospheric Administration (NOAA),  it generally occurs alternatively every 3 to 5 years, however it has historically varied at the outskirts 2 to 7 years.

          Before we can fully understand why this happens, we must first understand three things about water. Firstly, we must understand that dense objects sink in water. Secondly, cold water is heavier than warm water because the water molecule contracts. Thirdly, salt water is heavier than fresh water because the salt ions have closely bonded to the water molecules. This will help us understand how the El-Nino Southern Oscillation works.

          The reason that El Nino and La Nina occurs is due to the variations of the generally constant easterly trade winds in the south pacific which in turn effect the movement and currents of the South Pacific Ocean.

          During a La Nina year, the winds on earth are blowing more strongly from east to west. This moves the warmer surface waters near South America towards the western pacific area: Australia and South-east Asia. This causes increased water levels, rainfall, and water pressure in the western south pacific, but for the east pacific it causes it to be colder than usual. While the warm water is being pushed to the west it piles up and displaces the colder waters below pushing that lower, colder water westward towards South America. When the cold, deep water gets to South America it replaces the warmer water that is being moved west by a process known as upwelling. This works as a general cycle – warm water in the west and cold water in the east. After the La Nina season winds return to their normal westward blowing thus decreasing the effects of the La Nina. This will stay constant for nearly 3 to 5 years before the next big change – an El Nino year.

          During an El Nino year the effects are opposite of the La Nina. For some reason the winds stop blowing westward, and as a result the water no longer piles up on the west but rather rushes back towards America and eventually settles more evenly along the south pacific with the warm water distributed along the top of the ocean while the cold water remains below. This causes rain and warmer temperatures along the coast of South America along with droughts in the south east pacific. Along with the direct affects, the El-Nino Southern Oscillation also affects temperatures and air currents worldwide. As the El Nino year subsides, the normal prevailing eastern trade winds returns and blows back the warm surface water towards the south east pacific and remains fairly constant for the next 3 to 5 years until the next La Nina.
Conclusion

          Although the El-Nino Southern Oscillation does affect temperature and weather, it does not affect the long term climate or temperature; it is a cyclical process which should not be taken as a sign of global climate change, global warming, or global cooling. Incidental weather is not a good indicator of climate change, but rather we need to be able to identify the natural processes which take place in our globe and account for them in our calculation to identify possible climate change. We need to find averages over long periods of time and identify trends. As we learn more about the natural oscillations and patterns of weather and temperature of earth, we will better be able to understand what is really happening on this earth.




Works Cited 

"Are Cold Liquids More Dense Than Warm Liquids? A Guided-Inquiry Activity." NASA. Web. 24 June           2011.

"Global Climate Change: Oceans' Effect on Climate." Missouri Department of Natural Resources. Web. 24 June 2011. .

"International Programs." Census Bureau Home Page. Web. 24 June 2011. .

"La Niña Frequently Asked Questions." National Oceanic and Atmospheric Administration. Web. 24 June 2011. .

Oregon. Mixing Fresh and Salt Water. Web. 24 June 2011.

Philander, S. G. H. "El Niño Southern Oscillation Phenomena." Nature 302.5906 (1983): 295-301. Print.

Terry, James P. Tropical Cyclones: Climatology and Impacts in the South Pacific. New York: Springer, 2007. Print.

"Thermohaline Circulation - Fact Sheet by Stefan Rahmstorf." Potsdam Institute for Climate Impact Research — PIK Research Portal. Web. 24 June 2011. .

United Nations. Web. 24 June 2011. .

Unites States. CIA. World Factbook Geographic Overview. Web. 24 June 2011. .
The World Almanac and Book of Facts. New York, NY: World Almanac, 2009. Print.

Wednesday, June 15, 2011

A Scientific Consensus on Global Climate Change?



          Imagine this: Over the period of several weeks you notice a small lump growing under your skin on your neck area. You are uncertain what it is or what it could mean but you know enough to know that it could be a dangerous cancerous lump. What do you do? Should you Google it? Should you ask your friends? Should you ask respected scholars? Should you go see a medical doctor? Or should you just ignore it and hope that it goes away?

          To most outsiders the answer seems very obvious – go see a doctor; He will know best what it could be and what to do about it. However, for those in similar situations, history has shown that each of the above answered have frequently been employed in such life or death choices, sometimes with fatal consequences. Does the doctor know for sure the answer? Rarely, if ever. Does he guarantee his solution will work? No. Does he guarantee it is even the best solution? No. But who better is there to answer those questions than a medical doctor? Surely not your friends or family, not one with a Doctorate of Philosophy in Music Theory, not those who yell loudest, but those who have the most training on the subject. We can apply this hypothetical situation to the current dispute over  anthropogenic climate change, commonly known as global climate change or global warming.

          There is very little debate among informed individuals of whether the earth has been getting warmer, all one must do to observe this is to look at the direct temperature reading that have been taken over the years.  I would assume that our thermometers wouldn't lie to us.   I also believe that most would concede that the potential extreme consequences that are proposed by some would have devastating effects on the earth and it's inhabitants. More in the limelight of the climate change debate is whether or not humans are causing this warming, whether the climate is changing a significant amount, and whether we can stop it. We figuratively have a large lump on our neck - there are vast evidences of climate change in the world today. The real question is: what are we going to do about it? Where can we go to get the best answers? Who are the doctors in this situation? Who are the experts?

          The experts, or doctors, in global climate change are those who are actively studying and publishing in peer-reviewed journals on the issue of global climate change. They are the climatologists , those who are trained and publish within the issues of the climate. Although everyone’s opinion does count if we want the best results and the best answers we must go to those who know the most about the issues. Further, just because someone has a doctorate does not qualify him to speak on the issue with authority. Once again, you would not go to one with a doctorate of philosophy in music to diagnose your potentially cancerous lump.

          So what do the experts in climate change say? In this article I will discuss three of the major measurements of this question:
  1. What is the opinion of individual experts? 
  2. What do the peer-reviewed research papers say on the matter? 
  3. What do prevalent and relevant societies have to say about the matter?  
          I will only examine singular instances and studies.

          In a 2009 poll by Peter Doran and Maggie Zimmerman, in which 3,146 earth scientists responded 75 out of the 77 (97.4%) published climatologists believed humans were a significant factor in changing mean global temperatures. The study’s results also show a general positive correlation between education and a belief in  anthropogenic climate change.

          Naomi Oreskes performed a study on 928 peer-reviewed abstracts between 1993 and 2003 that had the key-word “global climate change” in which she reviewed the abstracts view on the legitimacy of anthropogenic climate change. She found that 20% explicitly endorsed  anthropogenic climate change, 55% implicitly endorsed it, while the remaining 25% did not take a stance on validity. Tellingly, there were no abstracts that explicitly rejected anthropogenic climate change.

          Julie Brigham-Grett stated in 2006, "...the AAPG [American Association of Petroleum Geologists] stands alone among scientific societies in its denial of human-induced effects on global warming." However, since 2006 that organization, AAPG, has changed its statement which, according to Bigham-Grett, means that no scientific body of national or international standing rejects the findings of human-induced effects on climate change.

          My conclusion in review of this and other such studies have lead me to believe that there is no significant debate among relevant practicing scientists about the validity of anthropogenic climate change. While there are people who are very intelligent, knowledgeable, and accredited who oppose anthropogenic climate change, there are also examples of intelligent, knowledgeable, and accredited people who dispute almost every scientific theory in any subject including gravity,micro and macro evolution, and the big bang.

          Will there ever be a complete consensus on global climate change? Probably not. Will the experts always have the best answer? Maybe not. But who would better know what to do than those who have dedicated their lives to this cause? I am content to believe the vast majority of leading scientists on the topics in the field. I am not a scientist, I do not know the majority of science behind global climate change, nor do I really feel a need to learn them to be confident in my choice. Climatology is not my field of expertise. My personal overarching questions are “who would know best?” and “who will I trust with my children’s lives?” With democracy widespread in most all progressive countries we have a personal moral responsibility and stewardship over this earth; our voices count. We need to listen to what the experts are warning us about and move forward with the best scientific knowledge that they have to offer.
Carbon Dioxide(CO2) Emissions by Country per Capita


Works Cited 

Brigham-Grette,  J., Anderson, S., Clague, J., Cole, J., Doran, P., Gillespie, A., ... Styles, B. (2006). Petroleum geologists' award to novelist crichton Is inappropriate. Eos, Transactions American Geophysical Union 87. p. 36. 

Doran, P., & Zimmerman, M. K. (2009). Examining the scientific consensus on climate change.           Eos, Transactions American Geophysical Union 90.3 : p. 22.

Census Bureau (2011) International programs. Census Bureau Home Page. U.S. 

Oreskes, N. (2004) Beyond the ivory tower: The scientific consensus on climate change. Science 306.5702.

Polling Report, Company (2011). PollingReport.com

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