Physics 6 Schedule

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Physics 6 Schedule
April 10 Fossil Fuels April 12 Times Beach Video
April 17 Video Discussion Alternative Energy April 19 Global Warming
April 24 Your Oral Reports April 26 Your Oral Reports
May 1 Your Oral Reports May 3 Your Oral Reports
Lab Friday
Earth Day April 20
Is the human race like the bucket of frogs about
to be boiled, led and bossed by happy frogs who
don't know they're in the same bucket?culturecha
nge.org
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Your Talks
April 24 (9 students) April 26 (5 students) Jau,
Whitbeck (15) Blue, Wuest (15) Reinagel,
Cotita, Majdili (20) Bonar (10) Gott, Tekle
(15) Hardy (10) Killian (10) Smith
(10) Towrey (10) 70 minutes 45 minutes
The class period is 75 minutes (300-415). You
are allotted 10 minutes if presenting alone, 15
minutes if two are presenting, 20 minutes if
three are presenting. If talks end early, I will
lecture.
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Your Talks
May 1 (6 students) May 3 (9 students) Burgdorf
(10) Durso (10) Glaude, Green (15) Heath
(10) McCarthy (10) Lurhsen, Wilburn
(15) McDuffee (10) Neyland, Payne (15) Salley
(10) Reilley (10) Stites, VanWagner
(15) 55 minutes 75 minutes
Uncommitted (1) Butler (10 minutes April 26 or
May 1.
The class period is 75 minutes (300-415). You
are allotted 10 minutes if presenting alone, 15
minutes if two are presenting, 20 minutes if
three are presenting. If talks end early, I will
lecture.
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Grading Your Talks
Tentative grading sheet environment-related
topic (0-3) scientific evidence presented
(0-5) effort by presenter to evaluate evidence
(0-4) talk organized and flowed logically
(0-5) evidence of thought on part of presenter
(0-5) good effort and enthusiasm (0-3) total
(0-25)
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You may use the computer and projector for your
talk. Here are some options
? Bring your talk on a CD and hope it works!
? A floppy (lets check that the computer has
one).
? E-mail your talk to me before noon on the day
you are talking (but earlier is better). Ill put
it a flash drive and on the network. I might even
get time to test it.
If your talk includes any video files, you need
to make sure they are provided and work (no
quicktime on the rooms PC).
If you want sound, let me know as soon as
possible so I can see if the speakers work.
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Remember
? The fact that it works on your computer doesnt
guarantee it will work on the classroom computer.
? If its important, have backups. At least two,
besides the original.
(Sooner or later, if you dont make backups, you
will suffer pain. Major pain.)
? Untested technology is guaranteed to fail if
you dont have a backup plan.
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Onondaga Cave
Take exit 214 (Leasburg exit).
Go south on Route H for 7 miles.
Go through Leasburg to get to Onondaga Cave State
Park.
The paved road ends just before you get to the
visitor center.
28 miles from exit 186 to exit 214, 7 miles to
park. Julia says 35 minutes. Park web site says
45 minutes.
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If you cross the Meramec river, youve gone too
far!
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Alternative Energy Sources
Finishing up
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Emc2
gravity
solar
nuclear
geothermal
geothermal
wind
fission
wind
tidal
tidal
fission
fossil
solar thermal
solar thermal
Solar energy comes from nuclear reactions in
the sun!
solar electricity
solar electricity
biomass conversion
biomass conversion
Renewable e.g., we use energy from the sun
today, and it gives us more tomorrow.
hydroelectric
hydroelectric
ocean thermal
ocean thermal
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Altamont (Patterson Pass) Wind Farm, California.
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The creator of the web site where I borrowed
these pictures says
The dangerous wind power plant is surrounded by
fencing, warning signs, and locked gates. Deadly
high voltage electric lines run under foot and
over head. Windmills can be seen lining the hills
in the distance.
Clearly, the natural shape of the hills has been
sacrificed for terraced foundations for the
decrepit windmills. No one who sees this can
claim they are better for the land, or much
different in appearance, than oil derricks, which
would be fewer and farther apart, and produce
more energy.
Something else to think about Local wildlife
researchers have received 2 million to find ways
to reduce the number of birds killed each year by
wind turbines. (Santa Cruz Sentinel)
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Here come some of my opinions again
If there is coal or oil in the earth somewhere,
humans will eventually go get it. Coal and oil
are too valuable to leave in the earth.
If there is wind to be farmed, humans will
eventually farm it. Its too valuable not to
farm.
I would rather not consider the scenarios under
which coal is not mined and wind is not farmed.
Remember, my personal values may have something
to say about the goodness of coal mining and
wind farming, but they are not relevant to the
present discussion.
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http//rredc.nrel.gov/wind/pubs/atlas/maps/chap2/2
-01m.html
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I can picture a giant windmill farm stretching
across the Great Plains from Texas to the
Canadian Border. Skip to slide 21.
Borrowing heavily from the wonderful (although
slightly old) Physics 162 course material at the
University of Oregon
Power that can be extracted from wind is
proportional to wind speed cubed.
KE proportional to V2.
Amount of air proportional to V.
Power proportional to amount of air times KE, or
V3.
27 more times energy in 60 mph wind than in 20
mph wind!
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Windmill efficiency is not 100. Large structures
impede wind flow (bad). High wind speed actually
lowers mechanical efficiency.
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To generate 10,000 KWH annual from a 20 mph wind
that blows 10 of the time windmill area
10,000 KWH/220 KHW per sq. meter 45 sq
meters this is a circular disk of diameter about
8 meters this is not completely out of the
question for some homes even a small windmill (2
meters) can be effective 20 mph 10 of the
time --gt 2500 KWH annually 40 mph 10 of the
time --gt 20000 KWH annually 20 mph 50 of the
time --gt 12500 KWH annually 4 small windmills
at 20 mph 10 of the time --gt 10000 KWH
annuallywould keep you powered up!
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The hypothetical Great Plains Energy
Project One turbine tower per square mile
stretched out from Texas to Canada. 300,000
total towers. Each tower 850 feet high.
(Important so as to get above friction induced by
ground based obstacles.) Each tower has 20
generators and is powered by a two blade
propellor of diameter 50 feet. Capacity of
single tower is 500 KW capacity so total capacity
is 150,000 Mega Watts (1/2 the US
consumption--1998). Note, we already have
600,000 oil wells in the US and no one seems to
mind.
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Ocean Thermal Energy Conversion
Underwater windmills!
No time to discuss! Could be hazardous to fish!
Hydrogen Power
Hydrogen
It's the most abundant element in the universe.
It promises limitless supplies of pollution-free
energy.
As long as you dont worry about the laws of
thermodynamics.
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H2 is a good way to transport energy from one
place to another.
But the hydrogen in the limitless supplies in
the ocean is in the form of H2O.
How are you going to get the H2 out of the H2O?
It takes energy. More than you get back when you
burn the H2. Answer nuclear power plants.
Hydrogen is not a source of new energy. It is a
potentially good way to transport energy that is
abundant in one location to another location
where energy is less abundant.
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Global Warming
Sources of Information
Information is not really so neatly packaged as I
will make it sound here but there seems to be 3
types of sources of information on global
warming.
Government agencies such DOE (Department of
Energy), EPA, NOAA, USGS, NASA (look under
climate change).
They tend to emphasize facts and present
information (sometimes too much!). They will
mention areas of speculation without drawing
conclusions.
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Environmentalist organizations.
Web site examples http//globalwarming.enviroweb.
org Natural Resources Defense Council
You will find lots of valuable information on
these sites. You will also find lots speculative
information expressed as if it were fact.
Why are they expressing speculation as if it were
fact?
Opinion they believe their speculation
represents the truth. They know it takes a major
emergency to wake up a democratic society. They
want to wake people up before its too late.
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Global warming skeptics.
Web site examples http//www.skepticism.net/faq/e
nvironment/global_warming/ www.globalwarming.org
Global warming skeptics, for a variety of
reasons, dont want government involved in
business or personal matters.
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Unfortunately, this seems to have turned into a
political debate between conservatives and
moderates.
Debates about science settle nothing. A theory
works or it doesnt. Nature doesnt care about
your opinion. Nature doesnt care about how good
you are at convincing other people you are right.
What do you do if a theory is inconclusive?
Discuss, argue, experiment, revise your theory,
experiment some more. Debate is for the Debate
Team.
Opinion there are no liberals left in this
country. Well, not enough to be worth counting.
Of course, nature, being inanimate, doesnt
care about anything.
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A personal note.
I am OK with you voicing your opinion.
I am OK if you disagree with me.
I am not OK if you want to force me to take
action based on your opinion alone.
I am very disturbed if you attempt to conceal
your motives behind a name.
I find its easy to tell when youre dealing with
an environmentalist. The skeptics may let you
know who they are, but you may have to do a lot
of digging.
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www.globalwarming.org seems to be run by an
organization called the National Consumer
Coalition. They believe in a free market
economy. Government has no business getting
involved.
The trouble is, I cant tell if the National
Consumer Coalition is really a coalition of
consumers.
Opinion the skeptics tend to argue by tearing
down, focusing on areas of disagreement and
dispute and claiming these areas are proof that
global warming is not real, when in fact, they
are only proof that science is being done.
Watch for inflammatory uses of words. Global
warming handwringers... If you have to make a
point by name calling, I question whether you
have a point.
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I should give equal treatment to the
environmentalists, shouldnt I?
Now that we know of massive species extinction
and a North Atlantic ice age right up ahead, the
question for any concerned citizen Is the human
race like the bucket of frogs about to be boiled,
led and bossed by happy frogs who don't know
they're in the same bucket?  We have met the
enemy and he is us.  Stop the global warmers!
http//www.culturechange.org/
Theres even an annual World Naked Bike Ride
Day to protest! If you cant make a point with
your clothes on, does taking them off make your
argument stronger?
censored
censored
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I would like to encourage informed skepticism. I
am disturbed by skepticism based on personal
biases.
http//www.skepticism.netthis is tricky!
The site is not very active these days. On
January 7, 2004, were 10 headlines on the site.
I saw 4 headlines and I said Yes! Yes! Yes!
I saw a headline and I said No! No! No!
I saw 5 headlines and I said Maybe! Maybe! Maybe!
(Need to read what he is REALLY saying.)
The web page author is a pro-gun, anti-campaign
finance reform libertarian. Up-front about it
(if you dig a bit).
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Why all this time spent on the Whos Who of the
global warming debate?
I dont believe in conspiracy theories. Never
attribute to conspiracy what can be explained by
human stupidity. Nevertheless, you cant be too
paranoid these days.me
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Global Warming A Definition
Do you think it would be a good idea to know just
what the discussion is about?
How about this for a definition
Global warming is the warming of the earth due
to the influence of humans, with a focus on
warming due to emission of greenhouse gases.
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What Do We Know?
1. The Planetary Greenhouse Effect
Without the greenhouse effect, we wouldnt be
alive.
So what is the greenhouse effect?
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No, no, no. Not that one. This one
typo?
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Actually, that picture contains at least one
common error. This one, from USA Today, is better
(in science content)
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I dont want to nitpick. If you want to say this
the greenhouse effect is caused when gases in
the atmosphere behave as a blanket and trap
radiation which is then reradiated to the Earth,
I wont stop you. But please visit the bad
greenhouse page to see why the sentence is wrong.
Also, a real greenhouse (or car in the sun) gets
hot because heated air is trapped inside it. Not
so with the atmosphere.
This is correct The surface of the Earth is
warmer than it would be in the absence of an
atmosphere because it receives energy from two
sources the Sun and the atmosphere.
Anyway, without this planetary greenhouse
effect, the earths average temperature would be
about -18 ?C (a bit below 0 ?F) instead of about
16 ?C (about 60 ?F).
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The planets give us some idea of the effect of
the earths atmosphere on its temperature. You
can go to planetscapes and look up planet
distances from the sun, and get an estimate of
the average temperature of each planet (and our
moon).
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Lets focus on the planets out to Jupiter (plus
our moon).
Ill discuss this in class!
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Im getting many of these nice images from GRID
Arendal, an environmental information center in
Arendal, Norway.
Do you trust Norwegians?
GRID Arendal was established by the Government of
Norway and the United Nations Environment
Programme.
Do you trust the United Nations?
Do you trust anybody who spells Program
Programme?
You can read GRID Arendals statement of values
here.
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If youre keeping score, the planetary greenhouse
effect is real and significant.
Score Global Warming Handwringers 1 Boss Frogs
in our Bucket 0
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2. Evidence of Past Climate Changes
If we see our climate changing now, maybe we
should see what it has done in the past.
Much of the following material comes from
http//globalwarming.enviroweb.org/. The sites
use of frames makes it difficult to give a link
for each quote.
Ill do my best to limit the discussion here to
topics outside the global warming political
debate.
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Seventy-five million years ago, the Earth's
average temperature was about 10F (5.6C) higher
than it is today. Almost everywhere the climate
was warm and humid.
How do we know that? Fossils of warm-weather
plants and animals living in places where its
too cold for them now.
OK, we dont know that, we infer that.
fossils of warm-water sea creatures, found in
South Dakota
In that sense, we dont know a lot about the
past other than through eyewitness reports.
In that sense, we dont know a lot about the
past other than through eyewitness reports. And
eyewitnesses have been shown to be the least
reliable of all witnesses.
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It is inferred that the greater temperature was
due to atmospheric CO2 from volcanic eruptions,
and to the fact that less of the land was above
water, so that there were fewer plants to take in
CO2 from the atmosphere.
20,000 years ago, ice covered 1/3 of the earths
land area, up to two miles thick in places, and
the earth was about 9F (5C) colder than it is
now.
How do we know? Fossils of cold-weather creatures
in currently-warm places. We saw other evidence
of the glaciers in the first video this semester.
Other clues about climate in the past ice cores,
tree rings, stalagmites, sediments that settled
on ocean floors.
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Possible reasons for cooling fewer volcanoes,
more land area covered by plants absorbing CO2,
more land area near the North Pole.
Most of us think of the Ice Age as being the
last time glaciers advanced on us from the north,
which reached a peak about 20,000 years ago.
Actually, the geological record shows evidence
for repeated Ice Ages, lasting millions of years
each. The current Ice Age is a couple of million
years old. The glacier advance 20,000 years ago
was just one episode of glacier advance during
the current Ice Age.
Thats all I want to discuss about past climate
changes right now. Here are the points I wanted
to make...
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10F warmer and Canada is a tropical jungle.
9F cooler and Illinois is buried under 2 miles
of ice.
A little temperature change makes a big
difference!
and the temperature changes appear to be
correlated with the atmospheres CO2 content.
and there have been huge climate changes in the
past, without any humans around to cause them ...
Humans have been lucky to live during a period
when the earths temperature is moderate and its
climate stable
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This is ammunition for both sides of the
political debate
Humans are not affecting climate if past climate
changes happened without human intervention, why
should the present be any different?
Humans are affecting climate if past climate
changes are related to atmospheric CO2, and
humans are putting CO2 in the atmosphere, why
should we not expect a change?
Score after the 2nd round Global Warming
Handwringers 1½ Boss Frogs in our Bucket ½
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Final note you dont have to believe any of this
climate change stuff if you dont want to.
If you choose not to believe it, you may not use
it in any of your arguments, either for global
warming or against global warming.
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3. Greenhouse Gases
The claim is that CO2 generated by humans isor
might beenhancing the planetary greenhouse
effect.
Lets see how that works. Or go to slide 53 if
time is short.
Every object that has a finite (non-zero)
temperature emits radiation. That radiation can
be modeled by something called a blackbodya
perfect absorber and emitter of radiation.
Right now I am emitting and reflecting radiation.
You see me because of the reflected radiation
(light). You cannot see the radiation I am
emitting unless you wear night vision goggles.
Blackbody is not a politically incorrect term
that physicists have neglected to abandon. It is
appropriate because objects at normal
temperatures emit this radiation at wavelengths
not visible to the human eye.
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The spectrum of blackbody radiation can be
calculated easily using simple quantum mechanics.
It is also easy to make a quite good blackbody
in the laboratory the theoretical and
experimental spectra agree quite nicely.
Here are blackbody spectra for an object at 37C
(about the temperature of your skin) and 100C
(boiling water).
All the radiation is in the infrared (invisible,
hence black).
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Above is the spectrum of blackbody radiation from
an object at a temperature of 6000 Kabout the
surface temperature of the sun.
If you are on-line, click here for an applet you
control the thermometer and view the resulting
spectrum.
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Heres a measured solar spectrum. It is not
smooth like a blackbody radiation curve because
there are other mechanisms for radiation of
energy from the sun.
However, the overall shape is described well by a
blackbody spectrum.
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So what does this have to do with global warming?
Good question. Notice how the amount of energy
radiated depends very strongly on the temperature
of the object.
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Lets start off with a cold earth with no
atmposphere and turn on the sun.
A cold earth radiates no energy.
As heat from the sun increases the earths
temperature, it begins to radiate energy (in all
directions, of course).
T
The earth will continue to warm up until it
reaches a steady-state condition, where the
amount of energy in equals the amount of energy
out.
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Now add an atmosphere
Now add an atmosphere. The atmosphere absorbs
some of the earths energy, warms up, and
radiates energy in all directions.
Some of the energy from the atmosphere reaches
the earth.
T
The earth warms up
radiates more energy
And eventually reaches a steady-state condition,
but at a higher temperature.
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So what does this have to do with CO2?
Good question. Nothing yet.
Remember the atmosphere?
Whats in it?
Duh. Youre showing me whats in it. Lots of O2
and N2. A little bit of CO2 and H2O.
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Each of these compounds, O2, N2, CO2, H2O, and
the rest, has a different chemical composition,
with different bonds and different rotational and
vibrational energy modes.
Each of these compounds, O2, N2, CO2, H2O, and
the rest, is particularly good at absorbing its
own preferred thermal energy.
Heres what I mean by that...
A couple of fancy terms, intended to convey the
idea that there is some physics behind all this,
without actually conveying any information to
this particular audience.
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CO2, because of its molecular structure, likes
to absorb radiant energies of these wavelengths.
Water vapor and ozone also have their favorite
wavelengths.
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Notice that CO2 is good at absorbing a large
part of the energy the earth is trying to radiate
away.
The same goes for water vapor and ozone.
Oxygen and nitrogen absorb at other wavelengths,
which dont represent a significant proportion of
the earths radiant energy.
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If CO2 absorbs this energy, what is it going to
do later?
Get rid of it. Radiate extra energy. Some of it
goes back to earth. A larger energy output from
the atmosphere means a higher temperature on
earth.
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T
Temperature goes up!
Greenhouse gas energy.
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Problems with this graphic it says blankets and
windows. I am OK if you want to think in those
terms. But see bad greenhouse for the technically
correct way of looking at this.
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Lets talk about this table for a minute.
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We have seen a mechanism by which CO2, and other
greenhouse gases, can increase the earths
temperature.
Points go to the Handwringers.
However, CO2 and Methane were entering and
leaving the atmosphere long before there were
humans around.
Points go to the Boss Frogs.
The referee awards ½ point to each side.
Score after the 3rd round Global Warming
Handwringers 2 Boss Frogs in our Bucket 1
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4. Evidence of Human Influence on the Atmosphere
The famous Mauna Loa CO2 data
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There are lots of other places to find this
figure, although the graphics are generally not
as pretty, For example, see the Carbon Dioxide
Information Analysis Center at Oak Ridge National
Laboratory.
The Mauna Loa data is significant because it
represents the longest continual monitoring of
atmospheric CO2
and the rate of increase of atmospheric CO2 at
Mauna Loa correlates with the amount of CO2 we
are putting in the atmosphere.
What would the Boss Frogs say?
You havent proved the excess Mauna Loa CO2 was
produced by humans.
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You havent proved the excess Mauna Loa CO2 was
produced by humans.
In a criminal trial, where proof is required
beyond any reasonable doubt, I agree.
In a civil trial, where proof is required that
seems more reasonable than not, I disagree.
The referee awards 1 point to the Handwringers.
Score after the 4th round Global Warming
Handwringers 3 Boss Frogs in our Bucket 1
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Hold on a minute. Lets not get carried away just
yet.
Global warming is the warming of the earth due
to the influence of humans, with a focus on
warming due to emission of greenhouse gases.
If you want me to believe it is happening, you
have to do the following
Give evidence that something is happening (an
effect).
Demonstrate a cause (or mechanism) for the effect.
Demonstrate a cause (or mechanism) for the
effect. ?
Show a connection between the cause and the
effect.
Show a connection between the cause and the
effect. ?
You have to eliminate other possible causes.
You have to provide other evidence that supports
your theory.
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5. Evidence for Warming
Im not presenting this logically, which would
be to first claim that the earth is warming, and
then present evidence.
Ive been presenting things that are known
first.
So is the earth actually warming?
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From the Global Change Research Information
Office (a Federal agency)
1997 for the Northern Hemisphere and for the
globe, 1995 was the warmest year of the record,
and proxy indicators such as tree rings suggest
this century is the warmest since at least 1400
AD.
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From the EPA
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Is something happening? Are there any questions
you should ask?
How do you measure global average temperature?
Can you even measurewith any confidence that
your measurements have meaningthe average
temperature of any place on earth?
Say you have a temperature station just south of
Rolla. Suppose its in an open field surrounded
by woods.
What if somebody chops down all the trees?
What if somebody replaces the woods with an
apartment complex?
What if Rolla turns in to a city of 500,000
population?
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These are good points the Boss Frogs bring up.
But if youve ever investigated how the weather
service (for example) measures temperatures, you
find that it is a much more complex procedure
than just sticking a thermometer in the ground.
In fact, to the best of my knowledge, the data I
have shown you have been corrected for
interfering effects. Heres an example of some
light reading.
Still, you can argue that global average
temperature is a meaningless concept. See here.
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Since 1979, satellites have been monitoring
stratospheric temperatures.
Volcanoes!
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However, it is not clear we know how to correctly
interpret the satellite data. See this.
New (May 2003) analysis suggests the satellite
data are consistent with global warming.
Are you getting confused yet?
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What do you think of this?
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Two slides of data from the University of Florida
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There are lots of data on global temperature.
Easy to get overwhelmed. Hard to know what is
significant. March 2004 was the warmest on
record, and it has been warmer since, but does
that mean anything?
The referee does not believed the Boss Frogs earn
any points for this round, but the Handwringers
have not scored a knockout.
The referee awards ½ point to the Handwringers.
Nobody gets the other ½ point.
Score after the 5th round Global Warming
Handwringers 3½ Boss Frogs in our Bucket 1
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6. Eliminate Other Causes
Hah! Not in my lifetime. This round of the match
will be going on for a long time.
Score after the 6th round Global Warming
Handwringers 3½ Boss Frogs in our Bucket 1
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7. Supporting Evidence
Im running out of time. Theres no way I foresee
getting here during a single lecture.
As one example, the sea level (a couple of slides
from here) has been rising, but it is not
possible to say for certain that the sea level
rise is related to the changing temperature.
I have many news reports Ive archived on my
computers, detailing little things that start
to add up butterflies too far north species
found where they dont belong ice melting in
places it shouldnt warmest month ever, second
warmest year, etc.
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more little things ? Austrias glaciers (the
Alps) are shrinking ? melting rate of Greenland
glaciers is speeding up ? Arctic ice is melting ?
Himalayan glaciers are melting ? Alaskan
permafrost is thawing ? massive beetle
infestation in Alaska (beetles not being killed
by the cold) ? Greenland ice cap is thickening
(due to increased snowfall from warmer air) ?
Atlantic conveyer belt slowed by 30 between 1957
and 2004 ? January 2006 warmest US January on
record ? Caribbean coral reefs dying after
warmest sea temperatures observed in 21 years of
monitoring ? Great barrier reef (Australia)
bleaching due to abnormal sea surface temperatures
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Without spending more time on this subject, I am
not ready to assign points.
Score after the 7th round Global Warming
Handwringers 3½ Boss Frogs in our Bucket 1
When you look carefully at what scientists are
actually sayingand understand a bit if
science-speakyou find that they are not as far
apart, or as close together, as the Boss Frogs or
the Handwringers would have you believe.
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8. Doomsday Scenarios
Go here for some light reading.
But remember, those people are Handwringers.
Global Climate Models, which predict the future,
are a source of abundant controversy. No matter
what a model predicts, each side will jump on the
result and say look, this proves our point.
We need to get the models right, so we can plan
for the future.
Another days lecture, and no time left.
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Where are We Today?
Heres the current situation, as I see it. Not
changed very much from the last time I taught
this course.
We have found a smoking gun in Prof. Plums
study.
Miss Marple says she saw his body there.
Sherlock Holmes says there is no body.
Inspector Lestrade says lock the doors, the
killer is sure to strike again.
You, the jury, should demand proof that the
smoking gun actually killed the body. But you
arent sure youll recognize proof when you see
it.
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What Should We Do?
Options for society (paraphrasing a Boss Frog)
Do nothing. Wait to see if there is really a
threat. Advantage cheap. Disadvantage you
arent preparing for the future.
More research, but otherwise do nothing. Find out
if there is really a threat. Advantage not too
expensive. Wont do anything rash. Disadvantage
delayed action may be useless.
Limited action, starting now, phased in over
time. Advantage less expensive than tackling the
problem head-on, right now. Wont do anything
rash. Disadvantage more costly, may spend money
on non-solution, limited action may not be enough.
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Full control of emissions, starting now.
Advantage tackles the problem right away,
quickly and thoroughly. Disadvantage very
expensive there may not even be a problem.
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What Should You Do?
Read, study, learn.
Be skeptical of claims from either side.
Be aware of peoples motivations.
Know whether an organization does science, or
selectively chooses scientific results to promote
its goals.
Understand that disagreement between scientists
is healthy, and not necessarily a sign that
anybody is wrong.
Be wary of those who demand 100 accuracy from
computer models.
Watch for words that bring an emotional response
(panic, hysteria, emergency, handwringer, boss
frog).
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A few links I want to keep for a while. Some
used, some not.
http//stommel.tamu.edu/baum/cdiac_01-10.html
data and indicators
http//www.ncdc.noaa.gov/oa/climate/research/2003/
jan/global.htmlTemp
http//www.forestry.uga.edu/warnell/service/librar
y/b1046/node7.html effect of different gases
http//www.usatoday.com/weather/wgrnhse.htm
http//www.grida.no/climate/vital/02.htm
http//globalwarming.enviroweb.org/ishappening/ish
appening_frameset.html 20000 yrs ago
http//www.pages.unibe.ch/ a past global changes
site
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Temperature change graphs
http//yosemite.epa.gov/oar/globalwarming.nsf/cont
ent/climate.html
http//darwin.nap.edu/books/0309068916/html/33.htm
l