A model for investigating Sun-climate questionslasp.colorado.edu/sorce/news/2005ScienceMeeting/posters/Zita.pdfWe welcome your ideas or requests for data analysis. Evergreen science

A model for investigating

Sun-climate questions

E.J. Zita and Gerardo Chin-Leo

The Evergreen State College

Olympia, WA 98505

<[email protected]> and <[email protected]>

Presented at SORCE meeting on Paleo Connections

Between the Sun, Climate, and Culture

14-16 Sept 2005, Durango CO

Abstract

We develop a model for investigating Sun-climate questions in aninterdisciplinary college classroom. A solar physicist and an biologicaloceanographer will work together in 2006 to identify key open questionssuitable for analysis by undergraduates, in an integrated academic program onclimate change. We will motivate investigations by reading current peer-reviewed articles. Teams of students will analyze data on each question andproduce a tutorial which synthesizes best current understanding. For example,what is the evidence for climate changes on the Gleissberg cycle (and othercycles)? Are apparent historical correlations between sunspot maxima andEarth temperature changes consistent with the period shifts in the relativebrightness of faculae? What is the role of ocean circulation in controllingEarth temperatures? How do historical indicators of shifts in ocean circulationcompare to effects of solar variability on Earth?

We welcome your ideas or requests for data analysis. Evergreen sciencestudents have a strong record of contribution to basic and applied research,from energy transport by solar magnetohydrodynamic waves to study ofplankton's effects on ocean albedo.

Investigating Sun-Climate questions, Zita, SORCE, 14-16 Sept 2005, Durango, CO

Outline

• Evergreen: Interdisciplinary studies

• Fire and Water program, Fall 2006

• Water: Oceans affect climate (Gerardo)

• Fire: Sun affects climate (Zita)

• Student research on real questions (your

questions?)

• Anticipated outcomes


Evergreen: Interdisciplinary studies

The Evergreen State College promotes student learning through:

Interdisciplinary Study

Students learn to pull together ideas and concepts from many subject areas,which enables them to tackle real-world issues in all their complexity.

Collaborative Learning

Students develop knowledge and skills through shared learning, rather thanlearning in isolation and in competition with others.

Learning Across Significant Differences

Students learn to recognize, respect and bridge differences - critical skills in anincreasingly diverse world.

Personal Engagement

Students develop their capacities to judge, speak and act on the basis of theirown reasoned beliefs.

Linking Theory with Practical Applications

Students understand abstract theories by applying them to projects andactivities and by putting them into practice in real-world situations.


Fire and Water, Fall 2006

Over geologic time the Earth has experienced wide fluctuations in climate, such as ice ages. Earthis currently experiencing a rapid warming trend. A major factor determining global climate is theintensity of the Sun's energy reaching the Earth. However, climate changes cannot be explained byvariations in solar radiation alone. Climate changes involve complex interactions betweenastronomical and Earth-bound processes. This program will examine some of these interactions.Specifically, we will examine how the Sun's output has varied over geologic time and recently. Wewill also examine how the oceans impact global climate by redistributing the Sun's energy andaffecting the composition of the atmosphere. We will discuss how changes in ocean circulationmay explain climatic changes over geologic time. We will also study how marine microorganismsplay a major role in the cycling of gases that affect climate. Finally, we will discuss contemporaryglobal warming, examining the contribution of human activities and fluctuations in solar output.We will critique proposed schemes to engineer solutions to global warming such as thesequestration of anthropogenic carbon into the deep sea.

Our study will examine various physical, chemical, geological and biological processes. Thisrequires a basic understanding of biology and chemistry as well as facility with algebra and anability to learn pre-calculus. The material will be presented through lectures, workshops,laboratories and seminars. We will draw on the primary literature whenever possible for arigorous scientific treatment of this topic. Students will do significant teamwork and will researchin depth questions of particular interest. We will have weekly online assignments, so studentsshould be comfortable using computers and the Internet.

Credit awarded in introductory physics, earth science, marine science, and environmental studies.

http://academic.evergreen.edu/curricular/fireandwater/


Water: Ocean biology affects climate

• Phytoplankton production is an important

sink of atmospheric CO2. Sinking of

phytoplankton biomass below the pycnocline

(“biological pump”) removes CO2 from

atmospheric circulation.

• Phytoplankton are important producers of

DMS (dimethylsulfide). This sulfur

compound contributes to the formation of

cloud condensation nuclei that affect the

Earth’s radiative budget.


Ex: Oceans affect climate

Plankton contribute to absorption and emission ofCO2, cloud formation, ocean albedo, and more.

Thermohaline cycle transports energy globally.


Fire: Solar irradiance affects climate

Pro: Greater solar irradiance L warmer Earth, right?

Con: Faint young Sun paradox (warm young Earth due toatmospheric/ocean effects?)

Pro: Maunder Minimum, Mideval Maximum, …

Con: Correlation or cause? Phase shift: sunspots higher Lnow, but lower L in past

Pro: Changes in Earth’s orbit or tilt changes in L changes in TE (spectral analysis - Milankovich cycles)

Many outstanding questions about proxies, correlations,and mechanisms.


Student research on real questions

1. Motivate student interest

2. Learn background concepts

3. Teams choose research questions

4. Facilitate student research

5. Student teams present and publish results


1. Motivate student interest

Seminar on high quality, accessible articles, such as:

• Living with a Variable Sun, J. Lean, Physics Today, 58, 32, June 2005

• The Sun’s Role in Climate Variations, D. Rind, Science, 296, 673, 26 April 2002

• Intergovernmental Panel on Climate Change (IPCC)

• Will marine DMS emissions amplify or alleviate global warming? Bopp et al.,Can.J.Fish.Aquat.Sci./J.Can.Sci.Halieut.Aquat., 61, 2002

• Influence of equatorial diatom processes on Si deposition and atmospheric CO2 cycles atglacial/interglacial timescales, Dugdale et al., Paleoceanography, 91, 2004

• Persistent Solar Influence on North Atlantic Climate During the Holocene, Gerard Bond,Bernd Kromer, Juerg Beer, Raimund Muscheler, Michael N. Evans, William Showers,Sharon Hoffmann, Rusty Lotti-Bond, Irka Hajdas, and Georges Bonani Science 7 December2001; 294: 2130-2136; published online 15 November 2001 [DOI:10.1126/science.1065680]

• A Pervasive Millennial-Scale Cycle in North Atlantic Holocene and GlacialClimates, Gerard Bond, William Showers, Maziet Cheseby, Rusty Lotti, Peter Almasi, PeterdeMenocal, Paul Priore, Heidi Cullen, Irka Hajdas, and Georges Bonani Science 14November 1997; 278: 1257-1266 [DOI: 10.1126/science.278.5341.1257]


Ex: Motivating student interest…

Friis-Christensen & Lassen (1991) Lean & Rind (2002) Lean & Rind (2001)

Evergreeners studying phytoplankton in local estuaries

2. Background concepts

Interactive workshops will develop understanding on basic

concepts such as:

• Scientific method, correlation vs cause, testing predictions, …

• Biological oceanography: biogeochemical cycles, phytoplankton ecology

& physiology

• Physics: forces, energy, heat flow, fluid motion, …

• Math: cycles, nonlinearity, computer modeling, …

• Measurement: spectra, isotope proxies, plankton density, …

• Atmosphere: convection, Hadley cells, …

• Ocean: T and salinity gradients, global conveyor belt, …

• Radiation and albedo: plankton, clouds, ice, …

• Carbon sources and sinks: plankton, trees, ocean warming,…

• Orbits, precession, nutation, Milankovich cycle, …

• Gaia hypothesis (forcing, equilibrium & stability)


Ex: Background concepts


Thermohaline cycle Fluid flows and energy flux Milankovitch cycle

3. Candidate research questions

What is the evidence for / mechanism of (choose a cycle): 11 years (sunspots), 22years (solar B field), 88 yr (Gleissberg: moon connection? Jose Rial), ~210 yr(Suess), 1500 yr (ocean interaction), 23 ky (precession), 40 ky (nutation), 100 ky(eccentricity)

Maunder Minimum, Medieval Maximum, faint young Sun paradox, …

(How) can small changes in L cause large changes in TE?

What is the evidence for (how often, how recent …is) this process:Warming ice melting damped ocean circulation cooling

What is the role of plankton in climate change: carbon sequestration,dimethylsulfide & clouds, albedo, …

How do changes in phytoplankton species composition affect the rate of CO2removal and DMS production?

Can atmospheric CO2 be removed effectively by fertilizing oceans? Side effects?

Is there a connection between lake levels and rainfall at Lake Victoria? (Boydand Schatten, pp.115, 132-134; Curt Stager)


Ex: Candidate research questions

Suggest your question here. Data for students to analyze?

J.Curt Stager, Lake Victoria levels, rainfall, and solar irradiance, in and out ofcorrelation due to ENSO? Phase shift due to changing sunspot/faculae ratio?

Debbie Sherrer, Stanford Solar Center (EPO) – radio signals in ionosphere

Ray Bradley and Michael Mann – compare data to T(t) hockey stick

Jose Rial - Eccentricity oscillations due to interaction between Earth’s orbitswith moon & planets Gleissberg cycle? Science 1999, GRL 1995

Julia Saba – pre-solar max jumps in Xray and EUV – compare to Dikpati/Zitasolar dynamo simulations – under what conditions does poloidal fluxrapidly rise to photosphere?

Plankton Mg/Ca combined with 18O to reconstruct past T, salinity (Lund,


4. Teams investigate research questions

Literature search: find and read references.

Discuss with team and faculty, deepen understanding.

Articulate hypotheses to address your question.

Find and analyze data, test your hypotheses.

Examine societal consequences.

Summarize learning in a research report.

Present tutorial in class, publish on class web pages.

Synthesize knowledge between teams big picture.


Examples of student research


Oceans and Plankton Physics & Astronomy

5. Presenting & publishing results

Teams draft research reports.

Submit them to class for peer review.

Present tutorials to class.

Seminar on tutorials to synthesize a broader view.

Present at local meetings, such as Evergreen Science

Fair, American Physical Society (NW section),

AAPT, AAS

Ambitious students draft articles for submission to

refereed journals.


Anticipated outcomes

• Analyze existing data

• Contribute to investigation of open questions

• Train & recruit new scientists

• Increase public scientific literacy

• Research results online


Acknowledgements

We acknowledge support from the Evergreen State

College in the form of summer program planning time,

And we thank the facilitators of the Faculty Institute on

Web Tools for their technical assistance.


References and sources of figures

Shindell et al. (http://www.people.virginia.edu/%7Emem6u/ssmrw02.html)

Robert Stewart (http://oceanworld.tamu.edu/NMEA_Talk/NMEA_Talk_2004.html)

ETE team (http://www.cotf.edu/ete/modules/coralreef/CRatmo.html)

Judith Lean and David Rind, Sun-Climate Connections: Earth's Response

to a Variable Sun, Science, Vol 292, Issue 5515, 234-236 (2001)

Friis-Christensen, E.; Lassen, K., Science, 254, 698-700 (1991)

D. Rind (courtesy of J. Lean), The Sun's Role in Climate Variations

Science, Vol 296, Issue 5568, 673-677 (2002)


References …

The Earth Institute, Columbia University(http://www.earth.columbia.edu/news/2005/images/conveyor_belt.gi)

Atelier Changement Climatique, ENPC(http://www.enpc.fr/fr/formations/ecole_virt/trav-eleves/cc/cc0304/cycle-carbone/cycle-

carbone.htm)

Richard Dewey, UVic, BC

(http://web.uvic.ca/~rdewey/eos110/webimages.html)

Scott Rutherford, Roger Williams Univ., RI, Milankovitch Cycles in

Paleoclimate, (http://deschutes.gso.uri.edu/~rutherfo/milankovitch.html)

E.J. Zita, solar physics research at Evergreen and HAO/NCAR

http://academic.evergreen.edu/z/zita/research.htm, http://www.hao.ucar.edu/


Followup

Ray Bradley, UMass Amherst, IPCC <[email protected]> (+ Michael Mann, hockey stick) T(t) data

Charles Perry, USGS, Lawrence, KS <[email protected]> model connecting solar variability with Mississippiflooding: http://ks.water.usgs.gov/Kansas/waterdata/climate/

Curt Stager, Paul Smith’s College, NY <[email protected]> Solar variability and rainfall at Lake Victoria,East Africa: http://webpages.paulsmiths.edu/~stagerj/website.html

Peter deMenocal <[email protected]>, Columbia, NY – Late Holocene variability of Atlantic surfaceand deep ocean circulation, cf Bond et al. article, Science 2001 (Planktons as proxies)

Jose Rial [email protected] , UNCarolina & CIRES at UCBoulder– Lunar influence on Gleissberg cycle?

-Earth's orbital eccentricity and the rhythm of the Pleistocene ice ages: the concealed pacemaker, 2004 Globaland Planetary Change, v. 41, iss. 2, p. 81-93.

- Abrupt climate change: chaos and order at orbital and millennial scales, 2004, Global and Planetary Change, v.41, iss. 2, p. 95-109.

David Lund, MIT/Woods Hole <dlund@whoi@edu>, Gulf stream variability during the last millenium –increased L -> more evaporation in Gulf Stream WOW, increased salinity during Maunder Min., centennialdroughts. Cf Haug et al., Southward Migration of the Intertropical Convergence Zone Through the Holocene,Science, Volume 293, Issue 5533, pp. 1304-1308 (2001). (Planktons as proxies)

Paul Mayewski <[email protected]>, Climate Change Institute (http://www.ume.maine.edu/iceage/),U.Maine, Polar ice cores, student learning resources (http://www.secretsoftheice.org/learning/index.html)


Documents

A model for investigating Sun-climate questionslasp.colorado.edu/sorce/news/2005ScienceMeeting/posters/Zita.pdfWe welcome your ideas or requests for data analysis. Evergreen science