Physical Fundamentals of Global Change Processesstock/lectures/PFGC0708/02_physfundgc_200… ·...

Phys.Fundament.GC-2007/08 www.pik-potsdam.de/~stock 02-1

Physical Fundamentals of Global Change ProcessesLecture 02: 16-Oct-07

Historical, Philosophical and Scientifical Fundamentals of GC• Some Essentials of Lecture 1• Historic Milestones of Science and Knowledge

–Renaissance: from the Middle Ages to the Modern Age –Discovery of the Globe and fundamentals of Earth Sciences–The Copernican Revolution–The Age of Enlightment, Reasoning, and Inventions–Example: Photosynthesis

• Towards the 2nd Copernican Revolution

University of Applied Sciences EberswaldeMaster Study Program Global Change Management

Manfred Stock Potsdam Institute for Climate Impact Research


Definition of Global ChangeChanges in the global environment (including alterations in

climate, land productivity, oceans or other water resources, atmospheric chemistry, and ecological systems) that may alter the capacity of the Earth to sustain life. (U.S. Global Change Research Act of 1990)

Social Systems

Climate System

S0

C0

E0Environmental

Systems

1)2)3)

4) 6)5)

Example:Global Climate Change Processes (anthropogenic)

1. Anthropogenic use of fossil energy resources 2. Anthropogenic emissions of greenhouse gases (GHG)3. Anthropogenic climate change4. Direct impacts of climate change 5. Indirect impacts of climate change6. Environmentally induced climate change (land use)


Planetary Temperature Control (Homeostasis)Daisy world - Earth System

T

t


Evolution of Life on Earth

Age [Ga] Major Transitions

• ~ 3.8 Emergence of Life (abiotic to biotic)

•3.5-3.0 Replicating Molecules (genetic code)

•2.8-2.6 Oxygenic Photosynthesis(unrestricted free energy capture)

•2.2-2.0 Great Oxidation (reducing to oxidizing atmosphere)

•1.9-1.2 Prokariotes to Eukcariotes(origin of phagotrophy, from asexual clones to sexual populations)

•1.2-.57 Protists to animals, plants and fungi(cell differentiation)

• 0.56 “Cambrium Explosion”


CAMBRIAN EXPLOSION• Biological Big Bang 540 million years ago• Most modern animal groups appear


The Scientific Evolution of Knowledge

catastrophic extinction of dinosaur predominance

10.000 years evolution of predominant human civilization (Holocene)


How many planets with life might be in the Milky Way?

Drake-Equation:http://www.pbs.org/wgbh/nova/origins/drake.html


Climate Change: The past 1000 years and this century

Global Change Analysis will show:

A continuation of the present business to use energy will most probably terminate the industrialized civilization on Earth and may even endanger Earth’s capacity to sustain life!

There is an urgent need for sustainable options of Global Change Management to alter the global energy system to ‘renewables’.


Renaissance: from the Middle Ages to the Modern Age



Europe: highly populated, biggest extension of agricultural crop land. The Great Famine of 1315-1317 kills millions of people



1342: extreme rainfall in June and July in Central Europe, strongest extreme flood event of the last 2000 years, all bridges lost in Germany, most of agricultural crop land lost due to erosion, famine, 1347-51: Black Death kills about one third of European population


From “climate optimum“ to the “Little Ice Age”(1550-1850)

Northsea Coastline900 - 2000© Henning Höppner

The Climate Historyof Central Europe1000 Years Weather, Climate, DisastersRüdiger GlaserPrimus, 2001 (German)

1612


Renaissance: fundamentals of modern philosophy

Thomas Aquinas an Aristotelian and an empiricist.

Fundamentals of Epistemology: the theory of knowledge


Epistemology: the theory of knowledge(Erkenntnistheorie)

According to Plato (428/427 BC – 348/347 BC), knowledge is a subset of that which is both true and believed (Wikipedia).

Aristotle's (384 BC – 322 BC) "natural philosophy" examines the phenomena of the natural world, including physics, biology and other natural sciences.

Detail of “The School of Athens”by Raffaello Sanzio, 1509, with Plato (left) and Aristotle (right)





William of Ockham a pioneer of nominalism and father of modern epistemology and modern philosophy in general, Summa logicae (Sum of Logic), before 1327.

‘Occam's razor’ states that the explanation of any phenomenon should make as few assumptions as possible.


Renaissance: discovering the globe

Age of Discovery

1455 Johann Gutenberg: letterpress1492 Martin Behaim: Nürnberg Terrestrial Globe1524 Peter Henlein: first pocket watch1568 Geradus Mercator: projection with parallel lines of longitude to aid navigation by sea (compass courses marked as straight lines).

Map of Fra Mauro, Venice 1459


World Map 1570 (Abraham Ortelius, Antwerpen)


Renaissance: discovering the globe

south-oriented map, made by the Arab geographer al-Idrisi in 1154,

Admiral Zheng He sailed from China to many places throughout South Pacific, Indian Ocean, Taiwan, Persian Gulf and distant Africa in seven voyages from 1405 to 1433 , some 80 years before Columbus. His "treasure ship" is four hundred feet long - much larger than Columbus's St. Maria.http://www.tourism-melaka.com/new/tourism/


Renaissance: The Copernican Revolution

Nicolaus Copernicus, De revolutionibus orbium coelestium (On the Revolutions of the Heavenly Spheres), 1543

The seven parts of Copernicus' theory are:1. There is no one center in the universe 2. The Earth's center is not the center of the universe 3. The center of the universe is near the sun 4. The distance from the Earth to the sun is imperceptible

compared with the distance to the stars 5. The rotation of the Earth accounts for the apparent daily rotation of the

stars 6. The apparent annual cycle of movements of the sun is caused

by the Earth revolving around the sun 7. The apparent retrograde motion of the planets is caused

by the motion of the Earth, from which one observes


Renaissance: fundamentals of Earth Science

Johannes Kepler, Astronomia Nova (New Astronomy), 1609, andHarmonices Mundi ("Harmony of the Worlds"), 1619, contained the three laws of planetary motion:

1. The orbit of a planet about a star is an ellipsewith the star at one focus.

2. A line joining a planet and its star sweeps out equal areasduring equal intervals of time.

3. The squares of the orbital periods of planets are directlyproportional to the cubes of the semi-major axis of the orbits.

T = orbital period of planeta = semimajor axis of orbit


1. The orbit of a planet about a star is anellipse with the star at one focus.

2. A line joining a planet and its star sweeps outequal areas during equal intervals of time.

3. The squares of the orbital periods of planetsare directly proportional to the cubes of thesemi-major axis of the orbits.

T = orbital period of planeta = semimajor axis of orbit

Kepler’s three laws of planetary motion (1630)

X

tor2 ∝ ror

3

tor = orbital period of planetror = semimajor axis of orbit





William of Ockham a pioneer of nominalism and father of modern epistemology and modern philosophy in general, Summa logicae (Sum of Logic), before 1327.

‘Occam's razor’ states that the explanation of any phenomenon should make as few assumptions as possible.

Knowledge is power


The Age of Enlightment


The Age of Enlightment

William Harvey, 1578–1657discovery of blood circulation


Rationalism - Cogito ergo sumRationalismwestern philosophical tradition begins with Eleatics, Pythagoreans, and Plato:Theory of the self-sufficiency of reason, leitmotif of Neoplatonism and Idealism.

Since the Enlightenment, rationalism is usually associated with the introduction of mathematical methods into philosophy, as in Descartes, Leibniz, and Spinoza.

René Descartes, 1596-1650

Cartesius

RefractionReduc(k)tionsm(De homines, 1622)

Scientificapproaches:

REDUCTIONSMand

HOLISM


The Age of Scientific Enlightment

Isaac Newton (1642-1727) built upon the work of Kepler and Galileo. His development of the calculus opened up new applications of the methods of mathematics to science. He showed that an inverse square law for gravity explained the elliptical orbits of the planets, and advanced the theory of Universal Gravitation. (Philosophiae Naturalis Principia Mathematica, 1678)

Newton believed that scientific theory should be coupled with rigid experimentation.

John Locke: Theory of Property


The Three Laws of Motion (Newton 1678)Newton's Laws of Motion describe the motion of a body as a whole and are valid for motions relative to a reference frame:

1. An object will stay at rest or move at a constant velocity in a straight line unless acted upon by an unbalanced force.

2. The rate of change of the momentum I of a body is directly proportional to the net force acting on it, and the direction of the change in momentum takes place in the direction of the net force: F = dI/dt

3. To every action (force applied) there is an equal but opposite reaction (equal force applied in the opposite direction).


Centripetal Motion in the Phase Space R(r,v)

rx

-rxry

-ry vy

-vy

vx

-vx

tor = 2π r / v

vy

-vy-vx

vx

-ay

ay

ax

-ax

tor = 2π v / a

⇒a = v² / rcentripetal acceleration⇒Fc = m v² / rcentripetal force

I

r

m

Using the phase space is a rather elegant and simple method to calculate the centripetal or centrifugal force, compared to the standard method via vector and differential calculus. The phase space is the coordinate system of all variables describing the state of a system.


Laws of Gravitation and Planetary Motiongravitational force between two bodies of mass m1 and m2separated by the distance r12

FG = - G m1 m2 / r122

G = 6.673 10-11 N m² kg-2

centripetal force accelerating a body of mass m1 and speed v1 on an orbit with radius r12

Fc = m1 v1² / r12

1.task: prove that Keplers 3rd law is a consequence of Newton’s3rd law expressed in the the relation: FG + Fc = 0

2.task: calculate the Earth’s orbital speed, using this relation and theparameters: mE = 5.98 1024 kg, mS =1.988 1030 kg, rES = 1.49 1011 mSolution:

Epot = - FG * rES = G mE mS / rES = 5.3*1033 J = Fc * rES = mE vE² ⇒ vE = 29.8*103 m/s


Titius-Bode “rule” for planetary distances

30.0639,5038.88Neptune

Pluto1

19.219.67Uranus9.5410.06Saturn5.205.25Jupiter

2.772.84Ceres1

1.521.63Mars1.001.02Earth0.720.71Venus0.390.40Mercury

real av.distance

DTBnPlanet DTB = 0,4 + 0,3 x 2(n-1) x sgn(n) Distances in astronomical units, AU. One AU is the average distance between Earth and Sun, roughly

AU = 149 598 000 km

The rule was proposed in 1766 by Johann Daniel Titius and "published" without attribution in 1772 by the director of the Berlin Observatory, Johann Elert Bode.

There is no solid theoretical explanation of the rule, but it is likely a combination of orbital resonance and shortage of degrees of freedom.

1 dwarf planet68,0077,29Eris1


The Age of Technical Inventions

James Watt (1736-1819) British inventor and engineer whose improvements to the steam engine (Newcomen 1711) were fundamental to the changes wrought by the Industrial Revolution.

Watt's idea was to separate the condensation system from the cylinder, injecting the cooling water spray in a second cylinder, C, attached to the main one through a valve V'. When the piston had reached the top of the cylinder, the valve V was closed and V' was opened. External atmospheric pressure would then push the steam and piston towards the condenser. Thus the condenser could be kept cold and under less than atmospheric pressure, while the cylinder remained hot.


The Age of Increasing Scientific Knowledge

Humboldt's quantitative work on botanical geography was foundational to the field of biogeography.

discovery of blood circulation

1676 Antoni van Leeuwenhoek: discovery of bacteria1761 John Harrison: invention of longitude Chronometer1779 Jan Ingenhouse: discovery of photosynthesis1850 Charles Darwin: “The Origin of Species”

Adam Smith: “Wealth of Nations”


Photosynthesis

6 CO2 + 6 H2O + Elight → C6H12O6 + 6 O2Carbon Dioxide + Water + Light energy → Glucose + Oxygen


Towards the 2nd Copernican Revolution:GAIM - Global Analysis, Integration, and Modelling


Earth System Modelling

Franck et al. (2002): Tellus 54B 325.

Kerogens are the precursors to hydrocarbons (fossil fuels), and are also the material that forms oil shales.

→ Biogeochemical Cycles(long-run processes)

Solar energy→

volcanism


“Hypotheses about Global Change are the less falsifiable the more they are relevant!”

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