Professor Geoffrey G Duffy
DEng, PhD, BSc, ASTC Dip., FRS NZ, FIChemE, CEng
Dr. Geoffrey G. Duffy, a professor in the Department of Chemical and Materials Engineering of the University of Auckland, NZ. Duffy received the New Zealand Science and Technology Silver Medal, in 2003 from The Royal Society of New Zealand. And has published 218 journal, peer-reviewed papers and conference papers including 10 patents and 62 technical reports.
Duffy’s full bio is here: http://www.ecm.auckland.ac.nz/staff/ggd
Climate is always changing, and always will. There are seasons. There are day-night (diurnal) cycles. At any one location, heat energy from the sun varies during the day. Energy from the sun is affected by local conditions and clouds. Heat absorption depends on whether it impacts water or land … and even then, the type of land (desert, forest, snow covered land), or the layout of the land (continental masses, or islands surrounded by seas). In some parts of the world temperatures are climbing on average, and in some areas they are dropping. Warming is not occurring everywhere at once and hence ‘global warming’ is a misnomer.
So what are the key players in ‘Climate Change’? The major driver is the sun. Warming depends on the sun. Cooling is due to the lack of sun’s energy. Radiant energy enters the earth’s atmosphere. Air (on a dry basis) consists mainly of nitrogen 78.08% and oxygen 20.94%. Of the 0.98% remaining, 95% of that (ie 0.934%), or almost all is the inert gas argon. Carbon dioxide CO2 is a trace. It is less than 400ppm (parts per million) or 0.04% of all the atmosphere (on a dry basis). Surprisingly, less than a fifth of that is man-made CO2 (0.008% of the total), and that is only since the beginning of the industrial era and the rapid increase in world population.
The atmosphere however is not dry! The next major constituent of air apart from oxygen and nitrogen is water, as a vapour and a condensed liquid. The atmosphere is comprised of about 1-3% water vapour [At 20°C and 100% humidity there is 0.015kg water/kg air or 1.5%: at 50% Humidity, 0.008kg water/kg air or 0.8%: and in warmer climate at say 30°C, 100% humidity, 0.028kg water/kg air or 2.8%]. Water vapour condenses to form clouds and it is by far the most abundant and significant of the greenhouse gases. Water accounts for about 95% of the greenhouse effect. The main atmospheric ‘intermediary’ between the sun and earth is water, and thus it dictates the behaviour of the earth’s climate. Without water vapour in particular and other greenhouse gases in the air in general, the surface air temperatures worldwide would be well below freezing. The sun clearly must be a much bigger influence on global temperatures than any of the greenhouse gases, even water and CO2. Carbon dioxide is about 1/60 of water in air!! It clearly is not the major player even though it is wise to minimise man-made emissions like particulate emissions, and CO2 and other gases where practically possible.
Variable and unstable weather conditions are caused by local as well as large-scale differences in conditions (wind, rain, evaporation, topography etc). They naturally induce either warming or cooling locally, regionally, or worldwide. We all have experienced how on a cloudy/sunny day that clouds strongly affect our sensations of both heat and light (infrared energy and visible light). Clouds do several things! The atmosphere may be heated by clouds by emitting latent heat of condensation as water vapour condenses. But clouds can both heat the atmosphere by reducing the amount of radiation transmitted, or cool the atmosphere by reflecting radiation. So of all the affects that can influence heating and cooling in the atmosphere and on earth, clearly water is the main greenhouse ‘gas’. Other greenhouse gases (carbon dioxide CO2, methane CH4, oxides of nitrogen etc) are 1/60 to 1/30 smaller in both quantity and effect. So with all ‘greenhouse gases’ including water, human activity accounts for only minute amounts, just 0.28% of the total greenhouse gases. If we exclude the key one, water, then human activity would only account for about 5.53% of the total greenhouse effect. This is minute in the total picture whatever way we look at it.
Unfortunately a lot of estimates and predictions are strongly based on theoretical computer models. Many now even trust models and their ‘theoretical results’ more than actual measurements and facts from reality. Computer analysis requires that the earth be ‘cut’ into small, separate areas (actually volumes), each being analysed for heat input/outputs and other gas/vapour fluxes. Even so the computational analysis domain size (basic computer grid elements) is huge, 150km x 150km by 1km high, with the current computer power. It is so large that the effects of even the very large clouds are not individually included; and that includes clouds in our visual horizon. The spatial resolution is therefore very poor. Supercomputers cannot give us the accuracy we need. Modellers therefore use parameters: ‘one factor fits’ all, for each of the domains (a kind of a ‘fudge factor’). This is sad, as water as vapour in clouds is 30 to 60 times more significant than other minute amounts of other greenhouse gases. Clearly climate simulations and thus predictions can be in serious error unless the actual cloud effects are well defined in the models. It is not only the number and spacing of the clouds in that 150 square kilometre area, but also cloud height effects, and cloud structure. These factors are not accounted for at all. Typhoons are still not represented in most models. Many tropical storms and local intense rain downfalls say in a 50km radius cannot be ‘seen’ by the models. Volcanic eruptions and large forest fires are extremely difficult to model. These emit enormous tonnages of small particulate matter that have immense shielding effects and interactions in the atmosphere. The slow diffusion of the smoke on windless days, and the more rapid turbulent dissipation on windy days are both very difficult to model or predict. We are simply ‘not there yet’ in the simplest events.
The inter-zonal effects of such larger-scale movements like the Gulf stream, or the El Nino–El Nina patterns, are not really greatly understood, and virtually impossible to model. The ‘noise’ (random fluctuations) in the results from the computer models is often greater than the magnitude of the computer readout results themselves! It is really surprising why model computer-forecasts are trusted for periods of say 30 – 50 or so years, yet weather forecasts are often very inaccurate even over a 2 or 3 week period. A good model should be able to ‘predict even the recent past’. The fact that these models cannot, clearly shows that we should shift our thinking and trust away from computer models to longer-term analysis of actual data, and to understanding the real physical mechanisms and processes (the ‘cause’ and ‘effect’ factors). Someone has said; “if tomorrow’s weather is inaccurately modelled and predicted, how can we pretend to predict long-term climate changes?”
Linearising short-term, random fluctuations in weather changes and temperature changes is scientifically untenable (weather and climate changes should be studied over very long periods if reliable trends are to be discerned). Much credence is given to the ‘hockey-stick effect’ of temperature data (upward swing in mean temperature over just the last decade or so) proposed and adopted by the IPPC (Intergovernmental Panel on Climate Change). Nations have grabbed this and are using this to base their policies for actions on global warming effects, and the implementation of controls on carbon-based emissions by carbon taxing. The very computer programme that gave IPPC those results was recently rigorously tested by inputing random numbers, and the computer-generated readout gave the same upward data trend with this meaningless input. This makes a mockery out the IPPC report and subsequent actions. Of course IPPC cannot admit to that now, as their report has been regarded as ‘gospel’ by many nations. In stunning direct contrast, actual data (not idealistic models) from remote sensors in satellites have continuously measured the world’s temperature and have shown that the trend in the warming period ended in 2001. Actual satellite measurements show that the temperature has dropped about 0.60°C in the past year, when compared to the mean recorded 1980 temperature. Observations from the Hadley Centre show that global temperature has changed by less than 0.050°C over the past decade! Also 1998 was distinctly warmer than 2006 because of the El Nino event. Why can’t we believe actual accurate data?
A man-made ‘greenhouse’ does not create new heat. A man-made ‘greenhouse’ can only increase the residence time or hold-up time of heat just like a blanket. Likewise in the atmosphere, the ‘greenhouse effect’ acts as a mechanism to smooth out fluctuations or rises and falls in temperature (that is advantageous). It is a dampener! It cannot be a dominant factor for global temperature change. It is the sun that gives the heat energy and drives temperature change. Simply, if the sun’s energy decreases, then the ‘global’ temperature will fall; with or without any greenhouse effect (and vice-versa).
But we must also consider the location of the effects. The surface of Earth is 70 % water. Water has a far greater heat carrying capacity than land; or even the atmosphere itself. Most of the incoming heat from the sun is absorbed by the seas and lakes (simply because they occupy 70% of the world’s surface area). When we compare that with land masses, a lower proportion of heat is reflected from watery zones to participate in the greenhouse effect. The greenhouse effect is mainly a phenomenon of the land surface and the atmosphere because land masses lose most of the heat they receive during the day by the action of overnight radiation. To multiply that effect, the atmosphere loses heat rapidly out into space by rainfall, convection and radiation, despite the greenhouse effect. So the large surface area of water over the world and the heat storage of water, are far more significant than any atmospheric greenhouse effect. The oceans really control the transport of water vapour and latent heat changes into the atmosphere (latent heat is heat needed to convert water-to-vapour, or conversely is given up when vapour goes to water), and this is far more significant than sensible heat changes alone (non changes in the state of water).
The seas take a long time to warm up or cool down when compared to land. This means the storage of total heat by the oceans is immense. As mentioned, heat energy reaching the land by day is soon radiated back out into space at night. But there are also zonal differences! The sun’s energy at the equator is consistent all year round, and in this region the larger proportion of surface area happens to be the ocean water. The dominant heat loss is primarily at the poles with each pole alternating as the main loser of heat. As a result there are severe cyclical variations in temperature with the seas and ice caps having the dominant effects in energy changes and hence temperature effects. If the erroneously-called, ‘global warming’ was occurring now we should see it now. Oceans would be expanding and rising; in fact over the past two years, the global sea level has decreased not increased. Satellites orbiting the planet every 10 days have measured the global sea level to an accuracy of 3-4 millimeters (2/10 inch inches) [see sealevel.colorado.edu]. Many glaciers are receding but some are increasing. Glacial shelves at the poles melt and reform every year because there are periodic seasonal changes; these alone show dramatically just what changes can occur from summer-to-winter-to-summer again and again. Dramatic changes? Yes; but they are perfectly normal and to be expected.
It is also important to highlight that CO2 is not a pollutant. It is vital for plant, tree, and food-crop growth. The basic principle of equilibria shows that when A and B make C and D, then C and D will react to form more A and B. Hence, as CO2 is produced, it will ‘react’ to produce more oxygen and cellulosic carbon through the well-known chlorophyllic process. Tree, plant, and food-crop production goes up markedly. With low amounts of CO2 in the air we would have severe food crop deficiencies. This process occurs with plankton too. But over and above this chemical-biochemical reaction is the simple physical equilibrium process of solubility. As the seas cool, more CO2 dissolves in the water, and CO2 in the air reduces (and vice-versa).
Other extremely important insights can be gleaned from the ice-core record. If CO2 was the main contributor to climate change, then history would reveal that the levels of CO2 would precede the mean temperature rise around the globe. In fact it is the opposite! Increases in CO2 have always lagged behind temperature rises and the lag involved is estimated to be 400 to 800 years. The core samples show that there has never been a period when CO2 increases have come before a global temperature increase. Any recent apparent temperature upward trend cannot be linked to CO2 increases. There is no physical evidence to support that. In fact there is the high probability that the more likely explanation of an overall warming trend is that we follow the ‘recent’ Little Ice Age, 400-600 years ago. There was also a Mediaeval Warm Period (MWP) that preceded that too!
The heat from the sun varies over a number of solar cycles which can last from about 9.5 years to about 13.6 years (the main one is the cycle of 11 years). The earth also has an irregular orbit around the sun. These and other effects like the gravitational effects of the planets of the solar system, combine to affect the sun’s magnetic field. Solar fares and sunspots affect the amount of heat generated from the sun. In fact, there is an excellent correspondence in general warming on earth with increased sun spot activity. The graphical correlation of sun-spot activity and the earth’s mean temperature changes is quite amazing. It appears that the activity of the dominant ‘heat supplier’ (the sun) has a far greater affect on weather (and therefore climate change) than any traces of atmospheric gases.
It is also interesting to note that NASA’s Aqua satellite system has shown that the earth has been cooling since 1998. This corresponds with measurements from the Argos sub-ocean probes that the ocean is cooling. This is in stark contrast with the proposals from many ‘climate alarmists’. The solar effect is huge and overwhelming and there must be time delays in absorbance and build up in energy received by earth and ocean masses. But the warmer the Earth gets, the faster it radiates heat out into space. This is a self-correcting, self-healing process.
The sun directly drives the El Nino–El Nina current motions that drive temperature changes world-wide. The sun sets up evaporative cycles, drives larger air and water currents or cycles, and changes weather patterns and therefore climate change. The varying degrees of lag and out-of-phase changes cause periodic oceanic oscillations. The El Nino Southern Oscillation (ENSO cycle) turns from warming to cooling depending on the net warming or cooling effect of the sun. This occurs quite rapidly. From about 1975 to 2000 there was a strong El Nino warming period (a positive Pacific Decadal Oscillation (PDO). Now there is a La Nina period, and this has a cooling or decrease in warming (negative PDO). In essence the ENSO and PDO switching is caused directly by the sun. Also there are similar periodic oscillations in other oceans (Atlantic and the Arctic oceans).
The panic to do something about climate change has led to some unrealistic and unsustainable actions. For example, Bio-fuels from grain will greatly increase food prices and roughly 30 million people are expected to be severely deprived. The USA will use up to 30% of the annual corn crop for alcohol production for vehicles alone. Ethanol production requires energy too to make it economically. The actual cost/liter is much the same as other liquid fuels, but the liters/kilometer consumed by vehicles is much higher than petrol, and well-meaning motorists will have to use far more ethanol. Just one tank full of ethanol for an SUV is obtained from enough corn to feed one African for a year. Worldwide the ethanol plant subsidies in 2008 will total $15 billion. A 2008 study on bio-fuels has shown that the CO2 emissions will actually double if carbon-rich forests are cut down.
Well, what about all the latest pictures, videos and TV programmes on climate change? Yes, there is a lot happening! Weather patterns are changing in many parts of the world and some catastrophic events seem to point to the earth warming. Even over our lifetime we have observed many weather pattern changes where we live. But what we observe (the ‘effect’) in a relatively small time-span cannot honestly be connected directly to any supposed ‘cause’ without investigating all the mechanisms that cause change. It is so easy to grab onto the notion that the increase in fossil-fuel burning and subsequent growth in carbon dioxide in the atmosphere is directly the major cause. Even from season to season we see snow and ice-covered mountains thaw, and massive areas of the Antarctic ice shelf melt, but in just 6 or so months they are restored. We are not alarmed at these annual changes! So why can’t we see that climate changes occurring all over the world now (not as big as these dramatic annual changes) are simply similar but on a larger time-scale. We have the ice-core and sea-bed core evidence at least to show us that this has happened in recent centuries. These are in harmony as to changes in CO2 with time and variations in temperature over time. There is no indication that one causes the other! History also tells us that there have been significant cooling periods over the last 1,000 years.
Climate and local weather is forever changing. Sure we must minimise pollution of our air and water systems with obnoxious chemical and particulates, and not treat them as ‘sewers’. But even doubling or trebling the amount of carbon dioxide will virtually have little impact, as water vapour and water condensed on particles as clouds dominate the worldwide scene and always will.
CARBON DIOXIDE CO2
BEST ESTIMATES OF THE LOCATION of CO2 as carbon (C)
Giga tonnes Gt (BILLION tonnes)
Atmosphere 750 Gt
Oceans – surface 1,000 Gt
Oceans – intermediate / deep 38,000 Gt
Vegetation (soil, detritus) 2,200 Gt
Annual EXCHANGE of CO2
Ocean surface – Atmosphere 90 Gt
Vegetation – atmosphere 60 Gt
Between Marine biota and Ocean Surface 50 Gt
Oceans( surface-to-deep) 100 Gt
Human emissions* (coal, oil, nat. gas) 6 Gt <2% 306 Gt