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Following (more or less) the book by William W. Hay (Professor Emeritus –University of Colorado, USA). A Course on Past and Future Climate. 1. INTRODUCTION. An Outline of the Course. Introduction The Language of Science Geologic Time Putting numbers on Geologic Ages
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Following (more or less) the book by William W. Hay (Professor Emeritus –University of Colorado, USA) A Course on Past and Future Climate 1. INTRODUCTION
An Outline of the Course • Introduction • The Language of Science • Geologic Time • Putting numbers on Geologic Ages • Documenting past Climate Change • The Nature of Energy received from the Sun I – Analogies with water Waves and Sound • The Nature of Energy received from the Sun II – Electromagnetic Waves • Exploring the Electromagnetic Spectrum • The Origins of Climate Science • The Climate System • What’s at the Bottom of Alice’s Rabbit Hole • 12. Energy from the Sun – Long term variations • 13. Solar variability and cosmic ays • I4. Albedo • 15. Air 16.HOH – Keystone of Earth’s Climate 17. The Atmosphere 18. Oxygen and Ozone 19. Water Vapor 20. Carbon Dioxide 21 Other Greenhouse Gasses 22. The circulation of Earth’s Atmosphere and Oceans 23. The Biological Interactions 24. Sea Level 25. Global Climate Change – The Immediate Past 26. Is There an Analog for the Future Climate? 27. The Instrumental temperature Record 11. Global Climate Change – The Future
Thinking about Earth’s future climate Shortly after taking office as President of the United States, Ronald Reagan decided to cut off scientific exchanges with Soviet colleagues, assuming that they were dangerous to our national security. As a geologist, I was odd man out in that small group of (otherwise) distinguished climate scientists meeting in Leningrad with a small group of Soviet counterparts. We were supposed to somehow find out if they really had a weapon that could change the weather. The Soviet group was headed by their most distinguished climate scientist, Mikhail Budyko, director of the Division for Climate Change Research at the State Hydrological Institute in Leningrad. Leningrad, now again St. Petersburg, is a beautiful city – the Venice of the north.
Mikhail Budyko Budyko pioneered the idea that serious climate change might occur in the near future. He recognized the importance of CO2 emissions as a factor in climate change. He recognized the importance of the ice-albedo effect. He realized that the Arctic was the ‘Achilles heel’ of Earth’s climate system
At a dinner in the Astoria Hotel I asked Budyko if the Arctic sea ice cover could really ever melt. He told me: “Its going to happen.” He thought it would be about the end of the next century. • The Arctic sea ice almost disappeared in 2007, that is when I realized things were changing faster than expected and started to write the book. • An even greater meltback is occurring in 2012. It’s going to happen.
Strolling back to my hotel after the dinner – almost midnight – the Winter Palace
Turning to look back -The General Staff Building from Palace Square
The Peter and Paul Fortress seen across the Neva from the Winter Palace just after midnight during early July – the bridges are starting to be raised
In 1975 Wally Broecker published a paper in the journal Science with the title • Climate Change; Are We on the Brink of a Pronounced Global Warming? • It had the following abstract: If man-made dust is unimportant as a major cause of climatic change, then a strongcase can be made that the present cooling trend will, within a decade or so, give way to a pronounced warming induced by carbon dioxide. By analogy with similar events in the past, the natural climatic cooling which, since 1940, has more than compensated for the carbon dioxide effect, will soon bottom out. Once this happens, the exponential rise in the atmospheric carbon dioxide content will tend to become a significant factor and by early in the next century will have driven the mean planetary temperature beyond the limits experienced during the last 1000 years.
Many people labor under the misconception that “global warming” means a gradual rise in temperature by a few degrees. • If that were the problem it would seem simple enough to take care of. Noel Coward noted in his song that “Only mad dogs and Englishmen go out in the noonday sun.” We could just stay indoors or in the shade. However, that is not all it means. • At the 1982 annual meeting of the American Association for the Advancement of Science in Washington, D.C., German climatologist Herman Flohn made the prophetic comment: • “Long before global warming due to CO2 can be proven, its effect will be noticed by extremes of weather, setting local records such as the highest and lowest temperatures, greatest and least rain and snowfall amounts, most powerful storms, unusually large numbers of tornados, etc. These indicate that the climate system is becoming unstable in response to the greenhouse effect.”
Global Warming or Global Weirding In 2010 Tom Friedman, in an Op Ed to the New York Times, suggested that we replace the expression ‘Global Warming’ by ‘Global Weirding’ because the effect of planetary warming is not evenly distributed and gradual, but is reflected by the unexpected extreme weather conditions suggested by Herman Flohn in 1982. Photo of Tom Friedman by Fred R. Conrad The New York Times
The author’s background • Education • BS Southern Methodist University • Junior Year in Munich – Ludwig-Maximilian Universität München - Germany • MS University of Illinois (Ostracoda) • Graduate study – Universität Zürich / EidgenossicheTechnischeHochschule -Switzerland • PhD Stanford University (Foraminifera) • Postdoctoral Year - Universität Basel –Switzerland - (Calcareous Nannoplankton)
The Author’s Professional Career At times he held two positions concurrently Italics = Guest Professor 1960-73 - University of Illinois 1967-82 - University of Miami - Rosenstiel School of Marine and Atmospheric Sciences 1968- Hebrew University – Jerusalem 1972-90 University College, University of London, Great Britain 1979-82 - Joint Oceanographic Institutions, Washington DC – DSDP/OMDP/ODP 1982-98 - University of Colorado at Boulder – Museum, Geology, CIIRES 1988-89 - Ludwig-Maximilian’s Universität – Munich, Germany 1990-2002 - GEOMAR – Christian-Albrecht’s Universität – Kiel, Germany 1993 - Universiteit Utrecht, The Netherlands 1993 - InstitutfürOstseekunde – Warnemünde, Germany 1995 - Universität Wien, Austria 1996 - Ernst-Moritz-Arndt Universität – Greifswald, Germany 2010 - Universität Wien, Austria
Retired from University of Colorado, Boulder, 1998 Retired from Christian-Albrecht’s Universität zu Kiel in 2002 Since 2002 he has taught intensive short courses in Paleoclimatology and Paleoceanology in: Amsterdam, the Netherlands Utrecht, The Netherlands Shanghai, China Milan, Italy Bremen, Germany Beijing, China Vienna, Austria Frankfurt am Main, Germany
What is science? Science is an unending voyage of discovery. Simply, it is a search for truth. Absolute truth seems to be restricted to mathematics. In all other fields we can only hope to make ever closer approximations to the truth. The search for truth involves making observations and performing experiments; in short, gathering factual information. The results lead to the development of one or more “hypotheses” to explain the observations or the outcomes of the experiments. An hypothesis makes predictions about the outcome of further investigations or experiments. Hypotheses that have passed many tests achieve recognition as being close approximations to truth and are referred to as “theories.” A theory which stands the test of time can become a “Law.”
Use of Semantics to Confuse the Public It is important to realize that the use of the word ‘theory’ in its scientific context is quite different from its use in everyday conversational English, where ‘theory’ is often used to refer to an hypothesis that has not been tested. Fundamentalist ‘Christian’ Creationists take full advantage of the fact that the general public is not aware of the different usage when they say “evolution is, after all, just a theory.” The fact that Darwinian evolution is considered a theory by scientists means that it has withstood many tests and been found over and over again to be the simplest explanation of observed facts. As Gerry Spence pointed out during the O J Simpson murder trial – a criminal trial is not a search for the truth – it is an effort to free or convict someone accused of a crime.
Occam’s Razor • William of Ockham, Franciscan monk • lexparsimoniae • "entia non suntmultiplicandapraeternecessitatem“ • ""All other things being equal, the simplest solution is the best." • Pope John XXII summoned him to Avignon in 1324 to stand trial for whatever crime this might have been
While the church authorities were trying to figure out what kind of heresy this was, William escaped to Bavaria where came under protection of Ludwig IV • Ludwig IV had himself named Emperor of the Holy Roman Empire • He then appointed another Franciscan monk, PeitroRainalducci, to be his own Antipope, Nicholas V, residing in Rome • Problem solved • The Incident is memorialized in the Munich suburb München-Schwabing by Occamstrasse
Experimental vs Observational Science • The experimental sciences develop knowledge by performing experiments. The are Physics, Chemistry, and Biology. • The observational sciences develop by observing nature. They are Geology and Astronomy. • Climatology is somewhere in between. We learn from laboratory experiments, observations, and now – by conducting a grand uncontrolled experiment on our own planet
An Early Warning The carbon dioxide theory is the only one that predicts a continually rising average temperature for the remainder of this century because of the accumulation of carbon dioxide in the atmosphere as a result of industrial activity. In fact the temperature rise from this cause may be so large in several centuries that it will present a serious problem to future generations. The removal of vast quantities of carbon dioxide from the atmosphere would be an extremely costly operation. If at the end of this century the average temperature has continued to rise and in addition measurement also shows that the atmospheric carbon dioxide amount has also increased, then it will be firmly established that carbon dioxide is a determining factor in causing climatic change. — Gilbert Plass, Texas A&M University, in The American Scientist, 1956.
The Grand Geophysical Experiment Human beings are now carrying out a large scale geophysical experiment of a kind that could not have happened in the past nor reproduced in the future. Within a few centuries we are returning to the atmosphere and oceans the concentrated organic carbon stored in sedimentary rocks over hundreds of millions of years.. This experiment, if adequately documented, may yield a far-reaching insight into the processes determining weather and climate. — Roger Revelle and Hans Suess, Scripps Institution of Oceanography, in Tellus, 1957.
Summary - What is science? • A search for truth • Observation • Hypothesis • Theory • Use of the word ‘Theory’ is different in science and common speech • Science – An hypothesis that has beeen tested over and over and found to be true becomes a theory • General – Pure speculation Religious fundamentalists: » Evolution is, after all, just a theory«
Civilization ‘Civilization’ has developed during the last 6,000 years This has been the longest period of climate stability in the last half million years • Sea level has been constant • Climate changes have been small and short-lived But then came the ‘industrial revolution’ And now Earth’s climate is becoming unstable and beginning to change
The natural course of events has been altered by humans • Development of agriculture • Domestication of animals • Urbanization • Industrial Revolution • Introducing greenhouse gasses • Changing the planetary albedo • Replacing C3 with C4 plants • Hard-surfacing the landscape • Changing the hydrologic cycle • Mining metals and fuels • Population Growth
All this leads to An uncertain future