Transcript Energy Systems & Climate Change

Welcome back to
Energy Systems & Climate Change
Winter Week 1 – Tuesday 10 Jan. 2012
The Evergreen St. College
Dr. E.J. Zita
[email protected]
Lab II Rm 2272
http://academic.evergreen.edu/curricular/energy/1112
Introduction to Winter ES&CC
• Returning students & new ES&CC students
• Last quarter – business as usual & consequences
• This quarter – alternative energies and Climate Change
science
• New Science Seminar students & Moodle site
• Your visions of the future
• Research projects
** Solar Workshop **
• Signup Sheets & looking ahead
• New students see me after class!
Schedule & everything is on our Webpage
http://academic.evergreen.edu/curricular/energy/1112/
Recap of Fall quarter
• Flows, growth, rates, …
• Graphing, calculating, and understanding
changes in time: linear and exponential
• Energy & power
• Water, fossil fuels, heat, …
• Estimation and Sig Figs!
• Your research projects
• Sustainability
Recap of Fall quarter Wolfson
• Earth’s history and changes
• Human energy use …?
• Humans can produce ~ 100 W; Americans use ~ 10kW
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Power = Energy / time, efficiency = out/in
Heat: mCDT,
mL, efficiency = DT/TH
Power: kADT/d, esAT4,
Fossil fuels & their consequences
Nuclear energy
Energy carriers: electricity & H2
Winter: Alternative Energies
• Solar energy
• Electricity & Hydrogen (homework)
• Water, Wind, & Biomass
• Geothermal, Tidal, Ocean energy?
Climate Change Science
• How the Sun works, and how it affects Earth
• How greenhouse gases and the greenhouse
effect work
• How the layers of Earth’s atmosphere interact
• Factors affecting Earth’s energy balance
• How we can measure Earth’s past and changes
• How to model Earth’s future
• Ideas for a better future
SciSem
Science Seminar (same structure)
• Themes: Climate Change & Sustainability
• Enroll yourself on the SciSem Moodle site using
the super-secret enrollment key:
SciSemESCC12
• Post Seminar PIQs, Essays, Responses, etc. here
• Check SciSem Moodle for updates to syllabus
and links to articles
Essays & Responses
(Signup & post on on Science Seminar Moodle)
Write one-page essays, 2 each quarter
• 350 words now (woo hoo!)
• If you did well with inquiry-based essays last quarter,
you may move on to thesis-based essays.
• Otherwise, or if you’re new, or if you find them useful,
please continue writing inquiry-based essays.
Write 2 responses to peers’ essays the week before
your essay is due (4 total)
Need volunteers for next week, please…
Homepage
Your Research Projects
Your Research Projects
• Online at our Research link
• Continuing projects – tell us briefly on Thus.
• Need a team or a teammate? Talk with each
other at break.
• Next Tuesday:
– Give 5-10 minute research updates
– then time to work on projects and get feedback.
Signup Sheets on Energy Systems
• Choose your team’s Wolfson Sections
• Choose your dates for Brief Reports – 2 each
15-minute workshop on
Your Visions of the Future
Take a couple of minutes to think about this
privately, and record your thoughts:
• What are the two most important variables in
determining the future of our climate?
• How much control do we have over each
variable?
importance
Climate variables: Importance vs control
More important
More important
Less control
More control
Less Important
Less important
Less control
More control
control
Put Post-It notes with your variables where you think they belong.
10 minute break?
Solar workshop
What does the brightness of the Sun depend on?
• Write down your ideas privately – 2 minutes
• Then fill out the workshop prediction sheet.
• You’ll test your predictions by building a “solar
motion demonstrator.”
• Make note of new insights along the way.
Factors affecting the amount of solar
energy that Earth receives?
1. Does it matter where you are on Earth?
2. Does the time of year matter?
3. Consider Olympia:
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Where does the Sun rise? Where does it set?
Where is it at noon?
When is it directly overhead?
Does it ever shine on the north side of your house?
Why is it warmer in summer?
Your predictions or hypotheses?
Make your Solar Motion Demonstrator
Test your hypotheses; note key points and surprises
Sunrise is usually NE or SE, not due east
Sunrise and sunset are due E and W only at Equinox
(and on those dates, day and night are equally long at every latitude)
The north side of a house in Olympia can get sunshine in the morning
and evening all summer.
The Sun is never directly overhead in Olympia – only in the tropics,
and only one or two days a year.
The path of the Sun depends on your latitude.
The rising/setting locations depend on the time of year.
Day length and temperature change more at the poles.
You can find the length of the day with your model. More?
Q&A
Q: How does path of the Sun depend on your longitude?
A: It doesn’t – longitude simply fixes the timing of sunrise.
Q. Would patterns be reversed in the S. hemisphere? Yes.
Q: What are the different poles on Earth?
A: Earth’s spin axis points at the North Star (for a few centuries.)
The magnetic axis is offset 11°, and wanders randomly.
Q: What would the seasons be like if Earth’s rotational (spin) tilt
from its orbital plane was different than 23.5°?
A: More tilt → greater seasonal differences
Q: How is the brightness of sunlight affected by its incidence angle?
A: Steeper angle → dimmer sunlight.
Northern summer: intense sunlight
in N. America
Summer vs winter
Southern summer: intense sunlight
in the S. America
Rotation (spin) vs Orbit Axes
National Weather Service – online school for Global Weather
http://www.srh.noaa.gov/jetstream/global/global_intro.htm
Rotation vs Magnetic Axes
Boston University: Short course on Earth’s Magnetic Field
http://www.bu.edu/cism/cismdx/ref/Labs/2005_AFWA_ShortCourse/Lab03/refs/EarthMagneticField.pd
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More questions & insights
about the motion of the Earth
and the variable Solar intensity?
There are long-termer effects, including
• sunspot cycles (decadal),
• Milankovitch cycles (26,000-100,000 yrs), and the
• slowly increasing luminosity of the Sun (billions of years)
Looking ahead
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3:00 Seminar in Sem II E2107
See Seminar Moodle for readings:
Thursday: first half of Big Coal
Friday: choose your sections of Wolfson
New students – see me after class
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Take our fall final exam
Closed book – except – you may use Wolfson
No help from people, computers, calculators…
Do your best
Turn it in Thursday before class
Break – then Seminar in E2107
Discuss Grand Solar Plan at 3:00