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Physics of Technology
PHYS 1800
Lecture 24
Introduction
Climate Change
Section 0
Lecture 1
Slide 1
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 1
PHYSICS OF TOF
ECHNOLOGY
- PHYS 1800
PHYSICS
TECHNOLOGY
ASSIGNMENT SHEET
Spring 2009Spring
Assignment
Sheet
2009
Date
Day
Lecture
Chapter
Feb 16
M
Presidents Day
17
Tu
Angular Momentum (Virtual Monday)
18
W
Review
19
H
Test 2
20
F*
Static Fluids, Pressure
Feb 23
M
Flotation
25
W
Fluids in Motion
27
F*
Temperature and Heat
Mar 2
M
First Law of Thermodynamics
4
W
Heat flow and Greenhouse Effect
6
F*
Climate Change
Mar 9-13
M-F
Spring Break
Mar 16
M
Heat Engines
18
W
Power and Refrigeration
20
F*
Electric Charge
Mar 23
M
Electric Fields and Electric Potential
25
W
Review
26
H
Test 3
27
F*
Electric Circuits
Mar 30
M
Magnetic Force Review
Apr 1
W
Electromagnets
3
F
Motors and Generators
Apr 6
M
Making Waves
8
W
Sound Waves
10
F*
E-M Waves, Light and Color
Apr 13
M
Mirrors and Reflections
Introduction
Section
0 Lecture 1 Slide 2
15
W
Refraction and Lenses
17
F*
Telescopes and Microscopes
Apr 20
M
Review
22
W
Seeing Atoms
24
F
The really BIG & the really small
INTRODUCTION TO Modern Physics PHYX 2710
May
1
F
Final Exam: 09:30-11:20am
No Class
8
5-8
5-8
9
9
9
10
10
10
No Classes
11
11
12
12
13
9-12
13
14
9-12
14
15
15
16
17
17
17
1-17
18 (not on test)
21 (not on test)
Homework Due
-
6
7
8
-
9
10
11
No test week
12
Fall 2004
* = Homework Handout
*Homework Handout
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 2
The Flow of Heat
– In radiation, heat energy is
transferred by electromagnetic
waves.
• The electromagnetic waves involved
in the transfer of heat lie primarily in
the infrared portion of the spectrum.
• Unlike conduction and convection,
which both require a medium to travel
through, radiation can take place
across a vacuum.
• For example, the evacuated space in
a thermos bottle.
• The radiation is reduced to a
minimum by silvering the facing walls
of the evacuated space.
Q
t
  A B T
Introduction
Section 0
4Lecture
1
Slide 3
 B  5.7 10 8 W / m 2 K 4
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 3
Heat Flow and the Greenhouse Effect
What heat-flow processes are involved in the
greenhouse effect?
Ein
Eout
Introduction
Section 0
Lecture 1
Slide 4
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 4
Energy Balance
(Conservation of Energy)
IN
OUT
j ~T
Introduction
Section 0
Lecture 1
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
4
Slide 5
temperature
energy
Climate Change
Lecture 24 Slide 5
Energy Balance
(Energy Conserved)
IN
OUT
Introduction
Constant
Temperature
Lecture 1 Slide
6
(Equilibrium)
Section 0
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 6
Energy Balance
(Excess Energy)
IN
OUT
Introduction
Section 0
Lecture 1
Slide 7
Warming
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 7
Energy Balance
(Energy Deficit)
OUT
IN
Introduction
Section 0
Lecture 1
Slide 8
Cooling
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 8
Ein
Eout
IN
Solar Input
Introduction
Section 0
Lecture 1
Slide 9
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Source: NOAA
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 9
Blackbody Radiation Problem
All bodies at T>0 K emit EM radiation. This process is called
blackbody radiation. The hotter the body, the more intensity
and the higher the average frequency of the emitted light.
Observations:
Blackbody radiation spectrum depends
only on the temperature of the surfaces
of the object.

Wien’s law
Introduction
Section 0

Lecture 1
Slide 10
Energy density (J/cm3)
Stephan-Boltzmann Law:
Q
Total Power 
  B T4 A
T
  5.6703 108 W 2
m K
lmax
The peak wavelength is
2.898
mm
lmax 
T
Wavelength (mm)
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 10
IN
Solar Input
Wien’s law
Stephan-Boltzmann Law:
Q
Total Power 
  B T4 A
T
  5.6703 108 W 2
m K

The peak wavelength is
2.898
mm
lmax 
T
The peakIntroduction
of the solar
spectrum
Section
0 Lecture
is at ~0.450 um wavelength (in
the green).
This corresponds to a solar
temperature of ~5800 K.
INTRODUCTION TO Modern Physics PHYX 2710
1

For a solar radius of 7·108 m, and
radiating surface area of 4/3 π r2, the
solar irradiance is
JSun=
W.
Slide 11
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 11
IN
Solar Input
Power Density at Earth’s Radius
The energy density at
the average Earth radius
is
2
 4 Section
 1
RSun0 Lecture
3

J E  J Sun 
2
 4  DSun Earth 
 3

Introduction
Power Input for Earth
The total power intercepted by the
Earth is
Slide 12

PEarth  J Earth  REarth
2

INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 12
Ein
Eout
OUT
Visible Reflection
Infrared Emission
Introduction
Section 0
Lecture 1
Slide 13
Infrared Trapping
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 13
Ein
Eout
OUT
Visible
Reflection
Introduction
Section 0
Table 1. Surface Albedos
Lecture 1
Surface
Albedo
Vegetation
0.2
Pale soil
0.3
Slide 14
Dark soil
0.1
Water
0.1
Clouds
0.5-0.9
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 14
Ein
Eout
OUT
Infrared
Emission
Introduction
Section 0

Lecture 1
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Stephan-Boltzmann Law:
Q
Total Power 
  B T4 A
T
  5.6703 108 W 2
m K
15
Slide

Here use the surface area of the Earth
and the equilibrium temperature of the
Earth.
Climate Change
Lecture 24 Slide 15
Ein
Eout
OUT
Infrared
Trapping
Introduction
Section 0
This is the greenhouse effect.
Lecture 1
Slide
First solve the equilibrium
16 problem without this term and
then with it.
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 16
Ein
Eout
OUT
Without
Infrared
Trapping
Introduction
Section 0
PIn  POut

B
TSun
4


 

  RSun2 
2
4
2



R


T
4

R
Earth
B Earth
Earth
2 
 D
Sun Earth 

so
Lecture 1
Slide 17


RSun

TEarth  TSun 
2 
 2 DSun Earth 
1
2
 280 K  7 C
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 17

Ein
Eout
OUT
With
Infrared
Trapping
Introduction
Section 0
Measured average T is ~ 298 K = 25 C
Difference due to greenhouse effect is ~12 C
Lecture 1
Slide 18
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 18
600
Projected Concentration After 50 More Years of
Unrestricted Fossil Fuel Burning
500
Paleo climate
400
300
280
260
CO2 [ppmv]
240
220
200
180
Section 0
Lecture 1
Temperature
Introduction
Slide 19
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
600,000
500,000
Physics of Technology—PHYS 1800
Spring 2009
400,000
300,000
200,000
Climate Change
Years Before Present
100,000
0
Lecture 24 Slide 19
600
Projected Concentration After 50 More Years of
Unrestricted Fossil Fuel Burning
500
Paleo climate
400
300
280
260
CO2 [ppmv]
240
220
180
Introduction
Section 0
Lecture 1
Slide 20
Temperature
Glacial
200
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
600,000
500,000
Physics of Technology—PHYS 1800
Spring 2009
400,000
300,000
200,000
Climate Change
Years Before Present
100,000
0
Lecture 24 Slide 20
triggers
Introduction
Section 0
feedbacks
Lecture 1
Slide 21
Sun
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 21
Mercury
333° F
Introduction
Section 0
Lecture 1
Venus
+855° F
Earth
59° F
Mars
-67° F
Slide 22
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 22
triggers
Sun
Introduction
Section 0
feedbacks
Lecture 1
Slide 23
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 23
600
Projected Concentration After 50 More Years of
Unrestricted Fossil Fuel Burning
500
Paleo climate
400
300
280
260
CO2 [ppmv]
240
220
200
180
Section 0
Lecture 1
Temperature
Introduction
Slide 24
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
600,000
500,000
Physics of Technology—PHYS 1800
Spring 2009
400,000
300,000
200,000
Climate Change
Years Before Present
100,000
0
Lecture 24 Slide 24
600
Projected Concentration After 50 More Years of
Unrestricted Fossil Fuel Burning
500
Paleo climate
400
300
280
260
CO2 [ppmv]
240
220
200
180
Section 0
Lecture 1
Temperature
Introduction
Slide 25
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
600,000
500,000
Physics of Technology—PHYS 1800
Spring 2009
400,000
300,000
200,000
Climate Change
Years Before Present
100,000
0
Lecture 24 Slide 25
600
Projected Concentration After 50 More Years of
Unrestricted Fossil Fuel Burning
500
400
Today’s CO2 Concentration
300
280
260
CO2 [ppmv]
240
220
200
180
Section 0
Lecture 1
Temperature
Introduction
Slide 26
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
600,000
500,000
Physics of Technology—PHYS 1800
Spring 2009
400,000
300,000
200,000
Climate Change
Years Before Present
100,000
0
Lecture 24 Slide 26
MODELS
Introduction
Section 0
Lecture 1
Slide 27
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 27
Introduction
Section 0
Lecture 1
Slide 28
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 28
triggers
Introduction
Section 0
feedbacks
Lecture 1
Slide 29
Sun
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 29
1980
Introduction
Section 0
Lecture 1
Slide 30
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 30
2007
Introduction
Section 0
Lecture 1
Slide 31
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 31
600
Projected Concentration After 50 More Years of
Unrestricted Fossil Fuel Burning
500
400
Today’s CO2 Concentration
300
280
260
CO2 [ppmv]
240
220
200
180
Section 0
Lecture 1
Temperature
Introduction
Slide 32
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
600,000
500,000
Physics of Technology—PHYS 1800
Spring 2009
400,000
300,000
200,000
Climate Change
Years Before Present
100,000
0
Lecture 24 Slide 32
After 45 More Years of current energy use patterns
600
500
400
Today’s CO2 Concentration
300
300
280
260
CO2 [ppmv]
240
220
200
180
Section 0
Lecture 1
Temperature
Introduction
Slide 33
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
600,000
500,000
Physics of Technology—PHYS 1800
Spring 2009
400,000
300,000
200,000
Climate Change
Years Before Present
100,000
0
Lecture 24 Slide 33
ground
observations
satellite
observations
balloon
data
sea surface
temps
continental
ice sheet
retreat
polar ice cap
retreat
mtn. glacier
retreat
permafrost
melt
ice cores
coral reef
cores
tree rings
Section 0 Lecture 1
BIOLOGICAL
DATA
Introduction
ocean
sediment
cores
Slide 34
WARMING
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 34
A Preponderance
of
Evidence
Introduction
Section 0
Lecture 1
Slide 35
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 35
These folks agree ...
National Academy of Sciences (United States of America)
Royal Society (United Kingdom)
Royal Irish Academy
Academié des Sciences (France)
Deutsche Akademie der Naturforscher Leopoldina (Germany)
Accademia dei Lincei (Italy)
Royal Swedish Academy of Sciences
Royal Society of Canada
Russian Academy of Sciences
Royal Flemish Academy of Belgium for Sciences and the Arts
Science Council of Japan
Chinese Academy of Sciences
Indian National Science Academy
Australian Academy of Sciences
Academy Council of the Royal Society of New Zealand
Academia
Brasliiera
de Ciências
Introduction Section
0 Lecture
1 Slide (Brazil)
36
Caribbean Academy of Sciences
Indonesian Academy of Sciences
Academy of Sciences Malaysia
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Source: IPCC TAR
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 36
And these folks...
American Meteorological Society (AMS)
American Geophysical Union (AGU)
NASA's Goddard Institute of Space Studies (GISS)
National Oceanic and Atmospheric Administration (NOAA)
National Center for Atmospheric Research (NCAR)
State of the Canadian Cryosphere (SOCC)
Canadian Meteorological and Oceanographic Society (CMOS)
Introduction Section
0 Lecture
1 Slide 37
Geological
Society
of America
Geological Society of London
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 37
And these folks...
American Association for the Advancement of Science
(AAAS)
American Physical Society / American Institute of Physics
American Chemical Society
Introduction
Section 0
Lecture 1
Slide 38
INTRODUCTION TO Modern Physics PHYX 2710
Fall 2004
Physics of Technology—PHYS 1800
Spring 2009
Climate Change
Lecture 24 Slide 38