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What you don’t know Can Hurt You. Climate Change. A Climate Change Reality Check. One Person’s Review of the State of Climatic Science, Specifically Anthropogenic (Human Produced) Greenhouse Gases versus Natural Climatic Variations. I. Introduction.
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What you don’t know Can Hurt You Climate Change
A Climate Change Reality Check • One Person’s Review of the State of Climatic Science, Specifically Anthropogenic (Human Produced) Greenhouse Gases versus Natural Climatic Variations
I. Introduction • The basis of this review is to ascertain if the evidence for anthropogenic climatic warming withstands scrutiny using the principles of the Scientific Method.
A Quick Review of The Scientific Method • The scientific method is the process by which scientists, collectively and over time, endeavor to construct an accurate (that is, reliable, consistent and non-arbitrary) representation of the world. • Recognizing that personal and cultural beliefs influence both our perceptions and our interpretations of natural phenomena, we aim through the use of standard procedures and criteria to minimize those influences when developing a theory. • As a famous scientist once said, "Smart people (like smart lawyers) can come up with very good explanations for mistaken points of view." In summary, the scientific method attempts to minimize the influence of bias or prejudice in the experimenter when testing a hypothesis or a theory.
The Scientific Method has four steps • 1. OBSERVATION and DESCRIPTION of a phenomenon or group of phenomena. • 2. FORMULATION of a HYPOTHESIS to explain the phenomena. In physics and in climatic science, the hypothesis often takes the form of a causal mechanism or a mathematical relation. • 3. USE of the HYPOTHESIS to PREDICT the existence of other phenomena, or to predict quantitatively the results of new observations. • 4. Performance of experimental TESTS of the PREDICTIONS by several independent experimenters and properly performed experiments. • If the experiments bear out the hypothesis it may come to be regarded as a theory or law of nature. If the experiments do not bear out the hypothesis, it must be rejected or modified. What is key in the description of the scientific method just given is the predictive power (the ability to get more out of the theory than you put in) of the hypothesis or theory, as tested by experiment. It is often said in science that theories can never be proved, only disproved. There is always the possibility that a new observation or a new experiment will conflict with a long-standing theory. (Wilson, E. Bright. An Introduction to Scientific Research, McGraw-Hill, 1952).
Example of The Scientific Method: • Einstein’s General Theory of Relativity • In 1905, while working at a Swiss Patent office Albert Einstein published four papers which would comprise the basis of the General Theory of Relativity, which he published in 1916. At first his papers were either ignored or heavily criticized as the established world of physicists were very skeptical of his theories. But his theories were tested, and proved to be correct. • The first major test was in 1919. His theory predicted that large gravitation bodies can deflect light. Astronomers made observations and found that sure enough during the 1919 solar eclipse, they could accurately measure the deflection of star light by the sun. • Einstein’s theories are still being tested to this day, NASA currently has several satellites (GRACE, LAGEOS, and in the future LISA) in orbit testing gravitation effects as predicted by Einstein to a much finer degree than has previously been possible. • Proper testing of the hypothesis of anthropogenic climatic warming must be done in a similar fashion, and examine its predictions against actual data.
II. Radiative Balance of the Planet • The earth is warmed by infrared radiation that is absorbed from the sun (about 235 w/m2). • The infrared radiation is transmitted through the atmosphere and absorbed by the earth’s surface by varying amounts, due the varied nature of the surface (ocean, snow pack, ice, soil, rocks, varied vegetation, human structures, etc.). • Some of the infrared radiation that is not absorbed is reflected back into the atmosphere which eventually transmits it back into space. • The balance of infrared radiation absorbed and infrared radiation reflected and transmitted into space allows the earth’s surface to stay at the relatively narrow range of temperatures. • This balance is controlled by the earth’s atmosphere, through its circulation systems and precipitation systems.
Weather and Precipitation Systems • The earth’s atmosphere is a complex circulation system,controlled by the 2nd Law of Thermodynamics which states that any system will try to come to an equilibrium. • In the case of the atmosphere that means that because of the vastly different temperatures and pressures of the atmosphere from surface (troposphere) to outer edges of the atmosphere (ionosphere) the atmosphere is constantly trying to balance the heating and cooling extremes that the addition of solar radiation on the atmosphere creates. • Thus weather systems constantly move warm and cold air around in the atmosphere, with the associated precipitation and condensation of water vapor. The result is cold and warm weather fronts, low and high pressure systems, and rain, snow, wind and all the types of weather systems. • The most important of these is the effect of precipitation systems. The process of evaporating water and then condensing and precipitating water moves heat up and down in the atmosphere.
How Precipitation Systems Move Heat - Part I • The difference in temperature from one region to the next causes air currents (wind) to blow across the surface of the earth, picking up heat from the surface and moving it to somewhere else. • The heat transferred to the surface from the overlying air is either sensible (an increase in air temperature), orlatent (water evaporated from the surface, adding water vapor to the air which contains the latent heat of vaporization). • Latent heat loss by the Earth’s surface through evaporation is the dominant method of cooling it. You feel this effect when a breeze blows over your skin. The breeze is taking heat from your body as the water on its surface evaporates into water vapor and is removed from your body. • At least 90 percent of the heat lost by water bodies (streams, lakes, oceans) is through energy required to evaporate water from surface. For land surface plants evaporate water through evapotranspiration. That is why forests feel cooler – the heat of vaporization is being removed from them.
How Precipitation Systems Move Heat - Part II • As air accumulates water vapor and latent heat it tends to rise. As the warm air rises it reaches levels of the atmosphere that are too cool to keep all the water vapor in vapor form. Now at 100 percent humidity some water vapor condenses releasing the latent heat and warming the upper parts of the atmosphere. This warming from condensational heating then causes the cloudy air parcels to continue to rise and condense more water vapor. This is how clouds and ultimately thunderstorms are formed. • If precipitation reaches the surface it represents solar energy that has been transferred from the surface to the upper atmosphere. • These columns of warm air force the dryer air around them to sink to fill the gaps left by the rising warmer air. This air as it is being forced downward warms the upper troposphere by emitting infrared radiation some of which is transmitted to outer space.
The Effect of Weather on Radiative Balance • If there were no precipitation and circulation systems and the transmitting effect of weather on heat and cold in the atmosphere the temperature on the surface of the earth would be about 140 F (based on a radiative heat model - Spencer, Roy F., 2008). The temperature would rapidly decrease with altitude and as low as 30,000 feet the temperature would be so cold that jet fuel would freeze or turn into a gel and make jet aviation impossible without more insulation and heating in fuel tanks. • Therefore precipitation systems on earth have the effect of being the earth’s air conditioning system, cooling the surface and transmitting the heat up and throughout the atmosphere. (Spencer, Roy F., 2008)
Present Day Composition of the Atmosphere • The atmosphere is made of a number of gases: primarily nitrogen (76.55%), oxygen (20.54%), water vapor (1.96%), and argon (0.91%). Other gases include carbon dioxide (0.03%) and the rest of the atmosphere (0.1%) is composed of methane, nitrous oxide, sulfur dioxide, helium, and other noble gases and trace gases. This is the current percentage of gases in the atmosphere.
Past Composition of the Atmosphere • However current gas percentages have in no way been constant over geologic time, and have varied considerably. For instance geologic studies have indicated oxygen may have been as low as 15 percent and as high as 30 percent of the atmosphere in the last 550 million years
Greenhouse Gases • The gases that primarily control the balance of infrared radiation absorbed and reflected are the greenhouse gases. • A greenhouse gas is defined as a gas that strongly absorbs and emits infrared radiation. The dominant greenhouse gases in the atmosphere are water vapor, carbon dioxide, and methane. • These and some of the minor other gases act as radiative blanket, causing the lower atmosphere to be warmer, and the upper atmosphere cooler. They do this by trapping more of the infrared energy that would be dissipated into outer space. Of these three, water vapor is by far the most important, causing over 95 percent of radiative absorbing or transmitting.
Carbon Dioxide Stability • From studies of the geologic record and associated indications of the composition of ancient atmospheres (in many cases by isotope studies and proxy measurements) , it has been determined the concentration of carbon dioxide has not been stable, but has also varied over geologic time.
The hypothesis of anthropogenic global warming is based on the following concepts: • Human activities have added carbon dioxide in the atmosphere by the use of carbon based fuels (oil, gas, wood, etc.). • The amount of carbon dioxide in the atmosphere is steadily increasing due to human use of carbon fuels. • The increase of carbon dioxide has caused a shift in the radiative balance of the earth’s atmosphere, resulting in an increase in the infrared energy retained by the atmosphere. • This retention of infrared radiation will be expressed by an increase in temperature in the lower and upper troposphere of the atmosphere, a general increase in atmospheric global temperatures, and by an associated increase in ocean temperatures globally due to natural circulation and equilibrium between the atmosphere and the ocean. • The described increases in global temperatures, lower and upper troposphere temperatures, and ocean temperature will be expressed by changing conditions on the surface of the planet such as warmer average temperatures per latitude, shrinking ice packs such as continental and alpine glaciers, and resulting rises in sea level. (Spencer, Roy F., 2008)
Computer Models of Earth’s Climate • Computer simulations of climate using mathematical representation of different aspects or parameters of the atmosphere are used to attempt to forecast long-term trends of the world’s climatic system. These models are very speculative in that the complexitiy of climatic systems do not allow accurate representation of most parameters. In most models several parameters, often cloud cover or solar radiation have to be given a constant value because of time and limitations of the computing power of the multiple processors used by the modelers. Each climate model can thus be very different as the modeler chooses which parameters to vary and the limits of the variation.
Key Assumptions for most Climate Models • Solar irradiance on the earth remains within a narrow range and can be considered a constant over time. • The historical record of concentrations of carbon dioxide in the atmosphere is best found in ice core data. • The primary greenhouse gases are water vapor, carbon dioxide, and methane. The global temperatures will reflect increases of carbon dioxide and methane. • Although water vapor is the primary greenhouse gas (95 percent of the greenhouse effect is by water vapor), its effects can be considered relatively constant except in its relationship to carbon dioxide and methane. • The effect of carbon dioxide alone on atmospheric warming is limited in that its ability to trap infrared radiation significantly decreases with concentration. Due to this property the doubling of carbon dioxide concentration alone will result in an increase of 1 degree Celcius in global temperature at most, assuming a completely static atmospheric model. • The effect of carbon dioxide is amplified by feedback mechanisms which cause other gases (particularly water vapor) to increase and thus increase the warming effect. • Ocean temperatures will change over time as the increase in heat in the atmosphere will be transmitted to the ocean.
Key Suppositions from most Climate Models • With increase in carbon dioxide, the temperature in the atmosphere will increase with altitude from the surface in the troposphere to an altitude of about 9 to 12 kilometers, and then decrease with the thinning of the atmosphere. This is the key mechanism of the hypothesis of anthropogenic global warming that causes the enhanced warming of the atmosphere. Increase in carbon dioxide causes the mid and upper level of the troposphere to heat up, transferring heat to the surface instead of being radiated out into space. • With increase in carbon dioxide the temperature of the oceans should also increase. This temperature increase is significant because the oceans hold much more mass then the atmosphere and thus can hold much more energy for feedback mechanisms (resulting in higher sea levels and more storms – hurricanes it is speculated). • With increase in carbon dioxide a positive feedback is predicted to occur with water vapor resulting in the increase of water vapor in the atmosphere and corresponding increase in temperature. Some modelers have stated that as the climate temperature increases the amount of this feedback could result in approaching a tipping point leading to catastrophic increase in atmospheric temperature.
Climate Model Parameters • These assumptions and suppositions are key in the modelers climatic predictions that anthropogenic increases in carbon dioxide will result in human induced climate change (global warming) leading to increases in global increases in temperature with resultant glacial and ice cap melting, increased and severity of atmospheric disturbances (storms), sea level increases, fauna and flora stress and even possibly catastrophic effects on the climatic system. • Each one of these assumptions and suppositions must withstand scientific method scrutiny in order for the hypothesis of anthropogenic warming to be considered valid, as with any hypothesis.
Assumptions: The Role of Solar Radiation • Assumption: Solar Radiation varies over a narrow range and can be considered a constant over time. • Astrophysicists tell us that sun irradiance varies according to distinctive cycles which are only poorly understood. The most frequent cycle is the 11-year sun spot cycle. This cycle has been tracked since the 1700s and is now between cycle Number 23 and Number 24. The chart on the next slide depicts this periodicity.
Assumptions: The Role of Solar Radiation • As can be seen from the previous chart solar radiation on the earth has been on upward trend the last two centuries. According to the Max-Planck Institute for Solar Studies “the level of solar activity during the past 70 years is exceptional, and the previous period of equally high activity occurred more than 8,000 years ago…during the past 11,400 year Sun spent only of the order of 10% of the time at a similarly high level of magnetic activity and almost all were shorter than the present episode.” Solanki, S.K. et.al. , Nature 10/28/04. • The next three charts show additional periodicities with sunspot and solar activity. Note the presence of the Maunder minimum between 1600 and 1700 and its relation with global temperatures and finally a summary of the past 3,000 years in global temperatures.
Cyclical warm periods that match solar activity (Stephen Wilde, 2008).
Summation of Global Temperature last 3,000 years From Robinson, A.B., et.al., Jrnl of American Phy & Surgeons, 2007.
Assumptions: The Role of Solar Radiation • The next slide shows how temperature has varied over the last 100 years as compared to the changing length of the sun spot cycle. • The following two slides then overlay other regions temperatures and corresponding and solar radiation.
Comparison of Solar Activity and Global Temperature Close correlation between surface land air temperature in the Northern Hemisphere (thick curve) and the changing length of the 11-year sunspot cycle (thin curve), indicating the varying intensity of the sun's eruptional activity (From Friis-Christensen and Lassen, 1991). Data taken from Landscheidt, Theodore, 2002, Figure 4.
Comparison of Solar Activity and Global Temp in Arctic From Robinson, A.B., et.al., Jrnl of American Phy & Surgeons, 2007.
Summation Solar Activity • Sun spot activity and thus solar activity has been historically recorded by observation for 1400 years. These observations have been confirmed by isotope studies. • The historical tracking of sun spots and global temperature have determined there is a strong correlation between them, although the mechanism is not entirely clear because the change in solar radiation is not sufficient to cause the degree in temperature change directly (using the radiative model method). • One current theory is that with decreased solar activity, the decrease in solar wind allows more cosmic rays from outside the solar system to penetrate the atmosphere, ionize nitrogen & oxygen atoms and provide more nucleating site for cloud droplets, increasing cloud cover and reducing global temperatures. Thus an indirect feedback mechanism. • Recent measurements have determined the last three decades of sun activity has been exceptional, with the most sun spot and thus solar activity in the past 8,000 to 11,400 years (Solanski, S.K., et.al, Nature, 2004). • The increase and decrease in global temperature this past century correlates strongly with this change in solar activity. • The recent drop in global temperature also corresponds to the current quiescent state of the sun, as it switches over from sun spot cycle 23 to 24. • Because of these facts, Climate models that assume the solar irradiance is a constant are seriously flawed and probably invalid.
Examination of Assumptions • Assumption: Ice core data is the best measurement of carbon dioxide concentrations in the atmosphere. • The IPCC and global climate modelers use ice core data and the amount of carbon dioxide trapped in gas bubbles in the ice core to measure the concentrations of carbon dioxide in the atmosphere. This has been the standard practice of climatologists for the past several decades. From ice core data it is assumed the pre industrial Holocene era (8,000 to 10,000 years ago) show a carbon dioxide level of about 240 ppmv (ppm by volume). • Modern carbon dioxide measurements are compared to the Mauna Loa observatory, which has been measuring carbon dioxide meticulously since 1958. The steady increase of carbon dioxide is assumed to be due to the use of carbon based fuel.
Evaluation of Carbon Dioxide Ice Core Data • Reliance on ice core data ignores 90,000 accurate chemical analysis of carbon dioxide in air made since 1812 using reliable chemical methods that usually achieved accuracy better than 3 percent. This data, when compiled, indicates carbon dioxide has had three maxima in the last 200 years around 1825, 1857, and 1942 with the later over 400 ppm (Beck, 2007). This data was not taken from specific station points for the purpose of examining carbon dioxide levels over extended periods, but collected as part scientific studies or measurements for other purposes. But, when carefully evaluated, there is no reason to assume this data is not useful as a historical carbon dioxide record. • Evaluation of gases in ice core data indicate they are not a reliable record of carbon dioxide as the carbon dioxide tends to differentiate and diffuse in cold liquid water and diffuses by the Knudsen diffusion effect at drastic pressure changes such as experienced by deep ice cores which minimizes variations and reduces maximums (Hurd, 2006). • Comparison of ice core data with proxy estimates of carbon dioxide (such as fossil leaf stomata indices) indicate ice core data consistently undervalues carbon dioxide concentrations by at miminum 100 to 200 ppm (Jaworowski, Zbigniew, Science, 2007).
Summation Ice Core Data • Climate models assume the preindustrial carbon dioxide levels were around 240 to 260 ppmv, based on ice core data. They also assume that the latest Mauna Loa station data indicates that carbon dioxide has increased steadily to maximum values for the past 100 years. • Ice core data has been demonstrated to be unreliable and the Mauna Loa data ignores prior data collected before the station initiation that found carbon dioxide levels above 400 ppm this century. • Therefore the basic assumptions of the climate models regarding current and past carbon dioxide level that are based on ice core data are demonstratably underestimated and therefore suspect and probably invalid. Values of historical carbon dioxide levels require further independent verification by other proxy measurements or direct measurements if they can be developed.
Carbon Dioxide Increases and Global Temperatures the past 200 years • Assumption: The primary greenhouse gases are water vapor, carbon dioxide, and methane. The global temperatures will reflect increases of carbon dioxide and methane. • The climate models and most proponents of global warming postulate that the dramatic increase in the use of fossil fuels as part of the industrial revolution (particularly after the 1850s) have caused the amount of carbon dioxide to steadily increase. This increase will be reflected in global temperatures because of increases in greenhouse gases and the resultant affect on the radiative balance of the planet.
Temperature Trends Last 150 years From Robinson, A.B., et.al., Jrnl of American Phy & Surgeons, 2007.
Comparison of Carbon Based Fuel Use and Global Temperatures 1. Comparison with use of carbon based fuel and global temperatures have found contradictory correlations for the past 150 years. 2. Increase in global temperature from the 1910 to 1940 compared to flat or small increase in carbon based fuels, and correlation was negative between 1940 to the late 1970s. Only positive correlation was after 1980s. Sea level rise and glacier shortening demonstrate no correlation. Solar activity actually correlates more closely. Robinson, A.R., et. Al., 2007.
The Relationship of Carbon Dioxide and Temperature over Geologic Time • Ice core data such as the Vostok ice cores have found that during the fluctuations of temperature that have occurred in the last 400,000 years, carbon dioxide values have increased and decreases in response to temperature changes, and have not been a driver of temperature changes. • Usually the maximum carbon dioxide concentration will follow a peak in temperature by about 400 to 800 years. • The explanation for this is probably the oceans and other water bodies that contain carbon dioxide are outgasing this molecule as they warm, like a can of soda outgases its carbonation as it sits.
Summation Carbon Fuel use and Temperature Correlation • A positive global temperature correlation with increase in fossil fuel use is observable only in last 20 years of last century. • Comparison with beginning or middle part of century flat or negative. • Solar activity actually is a better fit for global temperature correlation.
