The Earth’s Record of Climate: A Focused-topic ... · Theissen - The Earth’s Record of Climate 343 Student Perception in the First Week of Class End of Course Perception A "I

ABSTRACTThe Earth's Record of Climate is an introductory geologycourse offered at the University of St. Thomas thatexplores the science of paleoclimatology and itsrelevance to the climate change of the last century. Mostundergraduate students that enroll in the course believethat climate change is a significant concern, but lackknowledge of the scientific basis or express importantmisconceptions about the problem. Students build thenecessary skills to work with different forms of earthscience data including oxygen isotopic data, fossils, andsediment descriptions. They also read and respond toarticles on climate change. Students demonstrate theirlearning with: 1) a final project in which they complete adetailed paleoclimate reconstruction 2) a final examessay in which they respond in a substantive fashion to aclimate change skeptic, and 3) the results of a Knowledge Survey. Knowledge Survey results show a significantincrease (1.17 points on a 3 pt scale) in student confidence by the end of the course. Representative comments fromstudent reports on teaching suggest that it bothchallenges them and increases their interest in earthscience. Numerical ratings from student reports onteaching are consistently higher (by 5% on average) thanthose for an introductory physical geology course that Iteach.

INTRODUCTION AND COURSE OVERVIEWIn the department of geology at The University of St.Thomas (UST) we have developed five introductorycourses that focus on specific topics of interest tostudents while at the same time providing a core set ofagreed-upon concepts that are critical for all studentsthat move on to become geology majors. These courseofferings are: Introduction to Physical Geology, Geologyof the National Parks, The Science of Natural Disasters,Environmental Geology, and the course I describe in thispaper. Part of the rationale for the redevelopment of ourintroductory curriculum was to increase studentlearning by offering topical courses that are morerelevant to their lives. As part of this effort, I havedeveloped a course called The Earth's Record of Climate(ERC) that explores the science of paleoclimatology andits relevance to studies of modern global climatic change. The course makes use of several inquiry-based learningtechniques (e.g. Haury, 1993), and takes aninterdisciplinary, earth systems approach that has beenadvocated by geoscience educators over the past decade(i.e. Ireton et al., 1997).

I developed this course because climate is a topic that is ubiquitous in the national discussion and there is aclear need for students to explore and understand whatscientific evidence, including the broad spectrum of pastnatural climate variability, tells us about the humanimpact on climate. Moreover, UST has a small, growinggeology department attempting to attract majors andminors. We expected that this course would attract a

different type of student than might choose to enroll in amore traditional geology course because of the relevanceof the topic.

Few geology departments offer a course onclimatology or paleoclimatology at the introductorylevel. Geology courses on these topics tend to be offeredas intermediate or upper-level electives for thosemajoring in the discipline. In contrast, many geographydepartments, including UST's, offer an introductorycourse on weather and climate. Such courses tend toemphasize the workings of the modern climate system,use textbooks such as Meteorology Today (Ahrens,2003), and take a spatial approach to exploring theclimate system which is a strength of the geographycurricula. The advantage of a geology course on climate,like ERC, is that it provides a temporal approach,something that is not well developed in geographycourses. For students, this temporal perspective is crucial in providing a solid context on how the climate change of the past century compares with the long history ofchange and in particular the significance of the rate andmagnitude at which climate change is now proceeding.ERC explores climate change on multiple timescales andillustrates connections between climate change and other pressing global concerns such as the consumption ofnatural resources and threats to coastal areas. The latestIntergovernmental Panel on Climate Change (IPCC)report (2007) makes it clear that our society is likely toface major challenges related to climate in our lifetimes.Because of the potential impact of this problem on all ofus, geology departments should consider offering acourse like this at the introductory level where bothgeology majors and the much larger number of terminalscience students can effectively be reached.

The purpose of the paper is to provide earth sciencefaculty with a model they might consider for anintroductory course with a focus on paleoclimatology. Inthis paper, I first discuss the course design process,including students' perceptions and misconceptionsabout climate change and the goals for the course. Next, Ipresent examples of key activities in the course thatstudents do to build skills and demonstrate theirprogress. Third, I explain the assessment tools used todetermine whether the desired goals for students arebeing achieved. The final section of the paper is adiscussion about some lessons I have learned in teachingERC and student feedback about the course.

COURSE DESIGN PROCESSIn a series of NSF-funded workshops, the NAGT hasstrongly promoted the idea that geology instructors startby thinking of our courses as enabling students to solveproblems rather than just teaching them about a topic(e.g. Tewksbury and MacDonald, 2005). They advocate acourse design process that can be encapsulated as:

1) Define the course context.2) Define overarching goals, mainly defined as specific

skills, for the course.

342 Journal of Geoscience Education, v. 56, n. 4, September, 2008, p. 342-353

The Earth’s Record of Climate: A Focused-topic IntroductoryCourse Kevin M. Theissen Department of Geology, University of St. Thomas, Mail # OWS 153, 2115

Summit Avenue, Saint Paul, MN 55105, [email protected]

3) Define subsidiary goals.4) Design the course to give students practice with the

skills that you want them to have at the end.

Course Context - In designing ERC I started out withthe critical question, "What is the context of this course"?ERC is an introductory course that meets three times aweek for 65 minute lecture sessions and is taught to amoderate to large number of students (65-85 students) ina large lecture hall. Additionally, students meet onceweekly in smaller groups for a two-hour lab session. Thegreat majority of students who enroll in the course arenon-science majors with little or no earth sciencebackground fulfilling one of their core requirements. In order to understand how my students view climate,their first assignment is a brief opinion paper on thefollowing question: "Do you believe that global climatechange is a significant issue or a minor one for oursociety? Give an example of a personal or educationalexperience that has influenced your ideas on climate

change." Some examples of student perceptions andmisconceptions are shown in Table 1. Whether they think climate change is a significant issue or not, in their papers nearly all students readily acknowledge theoverwhelming scientific evidence of a human impact onclimate. Only a few students in each ERC offering haveexpressed skepticism about a human link to climatechange. As for the more debatable (political)aspect--whether it is a significant issue for society ornot--a clear majority of students (83% in fall 2007offering) express the view that climate change is asignificant issue and that there is a need for action tocombat the problem. A smaller number of them (17%from fall 2007 offering) believe climate change isoccurring, but is a minor issue with little importance totheir lives.

A number of students perceive climate change to bethe cause of warmer and less snowy winters inMinnesota, or the cause of other changes in the seasonalweather they have observed in their lifetimes (21% from

Theissen - The Earth’s Record of Climate 343

Student Perception in the First Week of Class End of Course Perception

A

"I do not believe that for our society this is a majorissue. I believe it is more of an issue for engineers andthe companies that produce products since they arethe only ones that can change how we respect theenvironment."

"My view has changed significantly. Before this course I believed humans had little to do with climate change and global warming but by looking at the data I ampositive we have the majority of impact on globalclimate change in the present day."

B"Over the years, countless people and organizationshave tried to swing me, and the public, one way oranother, yet my views are still very neutral."

"I was always indifferent as to the global climate,almost taking it for granted but this course absolutelyopened my eyes as to our effects as well as whatcan/will/should happen."

C"…the evidence that we… have altered the balance ofgreenhouse gases such as CO2 and NO (among others) cannot be ignored."

"I would not say my view has changed much-I cameinto the course with the belief that it is something weneed to be concerned with. What we have studied hasbeen all the more convincing."

D"The climate crisis has incredible moral implications. Ibelieve this is an ethical issue which will determineour character…"

"My view of global climate change has been enhanced. This class has given me extra confidence in my desireto protect the environment…"

E "I honestly don't think it is significant issue for oursociety. It is just something we have to deal with."

"Before I took this course I thought global warmingwas a joke and only tree-huggers worried about it. Inow can see that it really is a relevant issue and needsto be taken seriously."

Student Perception in the First Week of Class Problem or Misconception"Another small example is how fast people get sun burntthese days compared to even the 1970's. My mom told meshe used to run around all day on the farm in the summerand not burn like kids do today…"

Anecdotal evidence, example does not apply. If there is anincreased incidence of sun burn this is more likely to be dueto destruction of stratospheric ozone, an important butdifferent issue.

"I think that the weather changes in the last 20 years is proofthat global climate change will continue and progressivelyget worse."

Timescale is too short. Student may be correct that climatechange will get worse, but twenty years of data are notenough to support this. Must take a longer view.

"Although I do believe that this is a cycle of the earth it isonly made worse by us humans."

Climate change is primarily or entirely natural or part of anatural cycle. Data for the past 50 years indicate humaninfluence has been the primary cause over that time.

"There is no reason to believe it isn't natural. Each year,volcanic eruptions produce more CO2 than human activitiesdo."

Climate change is primarily or entirely natural or part of anatural cycle. This is an example where the student isfactually incorrect. Human emissions of C are an order ofmagnitude greater than volcanic sources.

"So many scientists and climatologists disagree on what iscausing global warming, to what extent greenhouse gasesare affecting climate, and so on…"

Scientific disagreement about the causes of climatechange. There is an overwhelming consensus on the causes.Existing disagreements are about specific future impacts and consequences.

Table 1. (A) Example written student perceptions of the significance of climate change in the first week ofERC and their final exam response on how their views had changed after taking the course. (B) Examplesof student evidence for or against climate change and the types of problems/misconceptions that theirresponses illustrate.

fall 2007 offering). Their responses also make it clear thatmany students use the media as a primary source ofinformation about climate change. Respondents oftenmentioned Al Gore's documentary, "An InconvenientTruth" or other films and television programs (28% of fall 2007 class).

The most frequent misconceptions that studentsshare involve their understanding of what constitutesgood evidence for a human link to climate change. Intheir written responses, several students pointed toimages of drowning polar bears or extreme weatherevents as compelling evidence of human-inducedclimate change, rather than the measured increases ingreenhouse gases or evidence from geological proxyrecords that the scientific community cites. In fact, onlyrarely do students refer to any "hard" data that a climatescientist would use in making a case for a human link.

Less frequently, students have the misconception thatmodern climate change is primarily due to naturalcauses or "cycles" as some students mention. Forexample, one student incorrectly believed that volcaniceruptions currently produce as much atmospheric CO2on an annual basis as human activities do.

Thus, ERC offers a great opportunity to challengestudents' preconceived ideas about climate change. Onthe ERC final exam students are asked "Has your view ofglobal climate change been influenced by this course?Why or why not". The most frequent theme in studentanswers is that after taking the course they are armedwith knowledge that will allow them to confidentlysupport their belief that humans have a significantinfluence on climate (Table 1). Those students who comeinto the course expressing ambiguity or not believing


Figure 1. Goals and assessment of the ERC course. The three overarching goals for the course are linked tospecific subsidiary (skills) goals and key activities that students do to build and test skills. Three assessments and knowledge survey results are used to measure student achievement of the goals.

climate change to be a significant issue have changedtheir minds by the end of the course.

Setting Overarching and Subsidiary Goals - A secondcrucial step in the course design process is to consider the question, "What do I want students to be able to do uponcompletion of this course?" This provides the focusneeded to develop a series of goals for students toachieve in the course and measurement tools todetermine whether they are being achieved (Figure 1).My rationale for choosing the set of goals we aim toachieve in ERC is that they are faithful to the focus onpaleoclimatology and serve the interests of bothnon-majors and majors in the course. Much of theemphasis is on the ability to work with a variety ofpaleoclimate data and other forms of earth science databecause all students, regardless of their major, shouldknow how to perform data analysis and interpretation.In light of their perceptions and misconceptionsdiscussed in the previous section, I also think that it isabsolutely crucial that students be able to understandclimate-related information (and misinformation) thatthey see in the print and television media and to makeinformed decisions about their impact on theenvironment based on sound scientific evidence.

The overarching goals of this course are thatstudents should: 1) Collect original data and accessmodern and past climate data from sources such as theinternet, analyze these data sets, make interpretations,and draw comparisons between different data sets; 2)Use different types of geological evidence (includingsediment and rock types, fossils, and geochemical data)to make an interpretation of the geological and

climate-related history of a given region; and 3) Makeinformed evaluations of climate-related arguments andinformation in the primary scientific literature andmainstream media.

The subsidiary goals for the course are: a) the abilityto access, analyze, and interpret data; b) the ability toapply the scientific method, carry out basic experimentaldesign, and perform data collection and reporting; c) theability to synthesize diverse data sets; d) the ability toidentify important rocks and minerals; e) the ability tounderstand and evaluate current literature onpaleoclimate and climate change.

Student achievement of these goals is measuredusing the results of a lab project, selected exam questions, and a Knowledge Survey taken by students in the firstweek of the course and again prior to the final exam.Examples of ERC activities that students do to worktowards each of the desired goals are described in thenext section.

COURSE ACTIVITIESWorking with Modern Climate Data: The Urban HeatIsland project - A number of studies have shown thatinstruction that engages students in the investigativenature of science produces better understanding ofscientific processes and enhanced critical thinking skillsthat might not be met by a more traditional curriculum(e.g. Haury, 1993; Apedoe et al., 2006). The first activitiesin ERC involve an inquiry-based heat island project forthe Twin Cities metro region where UST is located. Heatislands make a nice starting point because they are awell-known phenomenon that can be used to illustrate


Figure 2. Data compiled and used by an ERC student comparing 24 hour temperature differences between arural and urban site in a heat island project report.

the concept of the Earth's energy balance in a relativelysmall, familiar area. Heat islands also clearly illustratethe importance of human influence on local climates. The series of in-class and laboratory exercises used in ERCare modified from those described by George and Becker(2003). In order to get some background, students areassigned a brief technical reading (Mills, 2004) andwritten response on the canopy layer heat island effect,and a peer-reviewed research paper on an urban heatisland in Mexico City (Jauregui, 1997) which we discussin small groups and as a class during lecture. Studentsuse this reading and discussion to prepare for their firstlab exercise in which they write a concise proposal fortheir own experiment to test for the existence of an urbanheat island in the twin cities metro area. As a group wethen discuss the advantages and disadvantages ofdifferent proposed methods and come up with a set ofconstraints for the actual analysis that students willperform. Students are given specific instructions onobtaining datasets for a recent 24-hour period and for 30years of monthly-averaged data from suitable urban andrural sites. They access the datasets on the internet andwork with the data using Excel (Figure 2). Two of thethree times I have run this experiment with students Ialso had them work in groups to collect their owntemperature data from around the twin cities usinghandheld thermometers as well. Ultimately, theyanalyze and interpret their datasets and write a 4-5 pagereport on their findings as well as the implications, andlimitations of the analysis. The grading rubric for thereport (Table 2) shows what students must do to

demonstrate their achievement of the desired goal. Based on their reports, most students recognize the basicfactors that contribute to the heat island effect and do areasonable job of interpreting the data, meeting therequirement for a "satisfactory" grade in their reports.Students achieve an "excellent" grade when they take this further and provide a set of thoughtful explanations fortheir results. Students' understanding of urban heatislands is also measured with exam questions thatdirectly test their understanding of the phenomenon.They are provided with data illustrating the changingheat island intensity over a 24 hour period in a NorthAmerican city and asked two multiple choice questionsthat require interpretation of the data. In the last two ERC offerings, 87% of students taking the first midterm exam(n = 120) answered the first question correctly, and 84%answered the second correctly. This was above the classaverage score for the multiple choice portion of theexams (80%). Thus, most students demonstrate theirprogress building the desired skills to achieve the firstoverarching goal for the course (Figure 1). The exercisehas the additional benefit of giving students experiencein thinking about and applying the scientific method, asubsidiary goal of the course.

Interpreting Past Climates - Our region has manyaccessible rock exposures that represent the warmer"Greenhouse" Earth of the Paleozoic during whichsouthern Minnesota was covered by an inland sea, aswell as excellent evidence of the more recent glaciationand deglaciation. Students participate in a half-day long


Excellent Satisfactory PoorThe Abstract gives a clear and

concise summary of the experiment andthe important results and implications.

The Introduction provides a briefdescription of the heat island effect,discusses at least one published accountof other work on urban heat islands, andexplains what was attempted with thisproject.

The Methods section provides acomplete description of methods withdetails of the equipment used, thetemperature measurements that weremade, where they were made, and howthe measurements were made.

Results are presented in a clear andthorough fashion, referring to theappropriate figures and tables to guidethe reader. The data that are reported areconsistent with the figures and tableprovided. Figures are neatly plotted withlabeled axes and both figures and tableinclude descriptive captions.

An excellent Discussion includeseach of the following: 1. whether theirdata support the existence of a heatisland and why or why not (and theinterpretation is reasonable based on thedata that has been collected andincluded in the report) 2. Examples of the factors that could have influenced theirresults are given. 3. How they mightimprove the methods and analysis. 4. Acomparison of their results to those fromone or more other published studies.

The Abstract provides a summaryof the results of the experiment that lacks clarity or contains unnecessaryinformation that has little to do with theimportant implications of theexperiment.

The Introduction provides most ofthe important background information to "set the stage" for the reader, but islacking one of the requirements listed foran excellent score.

The Methods section provides apartial description of the methods, butfails to complete one of the requirementsfor an excellent score.

The author fails to report the Resultsin a clear and thorough fashion, and/orfails to guide the reader by referring tothe appropriate figures and tables.Nevertheless, the data that are reportedare consistent with the neatly plottedfigures and table they provided.

A satisfactory Discussion missingone of the important items listed above.For example, the factors that might haveinfluenced their results are either notdiscussed or are not reasonable.Alternatively, all of the items for an"Excellent" score are discussed, but onlyin a very brief or vague fashion.

The Abstract fails to summarize theresults or important implications of theexperiment.

The Introduction is lacking morethan one of the requirements listed above.The author provides a poor description of the Methods, failing to describe two ormore of the important items listed above. In the Results section, the authorincorrectly reports the data based onwhat is shown in the figures and tablethey provided. Alternatively, thesupporting figures and table are missingor were plotted incorrectly

A poor Discussion is missing morethan one of the important items listedabove for an "Excellent" score.Alternatively, the interpretation of thedata is inconsistent with the results. Forexample, the author claims that theirdata support the existence of heat islandwhen the data are ambiguous or do notsupport the claim.

Table 2. Grading rubric used to evaluate student Heat Island Reports for the course.

field trip to Interstate Park, near Taylors Falls, MN. Theyare instructed to take detailed notes on each of severalrock exposures that we visit in the park. Together weexamine exposures of Proterozoic basalt, Cambriansandstone, and Pleistocene glacial till in the park. Wethen discuss the depositional environments and climatesthat are indicated by these rocks and sediments andexamine further clues in the form of glacial potholes,sedimentary structures, and landforms. Uponcompletion of the field trip, students are assigned tocreate an informative brochure on the geology of thepark for the general public that explains the significantdepositional and climate episodes represented in thepark.

Later in the course students apply the skills from thisand other field lab exercises to complete a lab finalproject. Working in pairs, students are challenged toreconstruct the past climate of a fictional region knownas MIACland (MIAC is the group of private colleges towhich UST belongs) based on a variety of data fromseven "study sites" around this region. The students must draw on all of the skills they have developed in line withcourse goals to complete the project. The students areexpected to provide a thorough detailed outline of thegeological and climate history of the region.

Student pairs are given a letter from their "client", the MIACland Science Foundation, describing what needs to be done to complete the project. They are given someimportant data from each of the sites that will benecessary in making their climate reconstruction. Thesedata include:

• A satellite map of the region showing site locationsand important physical features

• Brief descriptions of rock types and their stratigraphicrelationships

• Unknown rock hand samples and outcropphotographs of sedimentary structures

• Information needed to calculate absolute radiocarbonage dates

• Oxygen stable isotopic data sets based on analysis ofmarine foraminifera and ice cores

• Downcore pollen, fossil, and sediment descriptionsfrom lake sediments

There is more than one possible interpretation forseveral of the episodes in this geologic history, butregardless of their interpretation students must back uptheir assertions with a well-reasoned explanation of thesupporting evidence for each step in their final report(Figure 3, Table 3). Students use the last two lab sessionsof the course to work on the project and consult withtheir instructors. Most students also spend aconsiderable amount of time working on the projectoutside of lab time. I have found this to be a challengingexercise for students, but one which they quickly become immersed in. Several students have told me that theyliked the "puzzle-like" aspects of the exercise.

Preparing Students to Evaluate Arguments aboutClimate Change - Students complete several exercisesthat are designed to help them achieve the thirdoverarching goal for the course (Figure 1). Students readpublished magazine and newspaper articles writtenabout global climate change and respond to selectedchapters from the "Two mile time machine" written byRichard Alley, a respected paleoclimatologist. They areinstructed to write brief responses (usually no more thantwo pages) to these articles in which they summarizetheir feelings on the scientific accuracy based on theircurrent knowledge and what they find persuasive andmisleading about the articles. Students write brief


Content Chronology Supporting Information

Excellent (90-100 pts)

This is athorough andhigh-qualityreport that isready forpresentation.

Descriptions of each step in thepaleoclimate history ofMIACland is included. Descriptions are clear, thoroughand well-supported by allavailable evidence. Trends, cycles, and aberrations in the oxygen isotopic data sets arediscussed, and the authors haveidentified climate forcings thatmight account for cycles.

All events in the paleoclimatehistory of MIACland have beenplaced in the correctchronological order. Where possible, absolute agedates have been calculated andincluded in the report.

All figures have been neatlyplotted and labeled. Allunknown rock and fossil samples have been identified correctly.

Satisfactory(70-80 pts)

The reportgets many ofthe importantelements right,however a fewitems can besomewhat orgreatlyimproved.

Two or three steps in thepaleoclimate history are missingor are not supported by theavailable evidence.Oxygen isotopic data sets arementioned, but discussion of thetrends, cycles, and aberrations inthe data is limited.

Two or three events in thepaleoclimate history have beenplaced out of order. Absolute age dates may have been incorrectlycalculated or were not includedin the report

Figures are included, but theyare not labeled correctly. Morethan one of the unknown rockand fossil samples wasincorrectly identified.

Poor(<60 pts)

This report has many seriousflaws andneeds a lotmore work.

Several of the steps described inthe paleoclimate history areinsufficient because they are notsupported by the availableevidence or were entirely missedby the authors.Oxygen isotopic data sets areeither not discussed in the reportor the data are misinterpreted.

More than three events in thepaleoclimate history have beenplaced out of order. Absolute age dates were incorrectly calculatedor were not included in thereport.

Figures are plotted incorrectly orare entirely absent. Severalunknown rock and fossil samples were incorrectly identified.

Table 3. Grading rubric used to evaluate student Final Projects for the course. Average results fall betweenthe "Satisfactory" and "Excellent" levels over five ERC offerings with n = 306 students.

response papers to each of these articles and bring themto the following class session where we discuss them as agroup.

The rubric for these responses is a simple three-pointscoring system with the following criteria:

(3 points) This is a thoughtful and thorough response inwhich the writer clearly responded to the questions thatwere posed in the assignment.

(2 points) This is a satisfactory response to the questionsthat were posed in the assignment, but it lacks the depthof examination that would merit a higher score.

(1 point) This response shows that little thought andeffort were put into it.

Examples of the written responses are shown in Table 4.

Earth science educators have found that role-playing activities, debates, and other active learning exerciseswork well when teaching about controversialenvironmental topics such as climate change (e.g.Schweizer and Kelly, 2005). Our final activity in ERC is

an Emissions Reduction Role playing exercise. The goalof this exercise is to give the students practice in bothdefending and critiquing different positions in theclimate change debate. Prior to the exercise, students aretold that they will be participating in a mock "UnitedStates Convention on Climate Change" in which theywill debate and vote on a bill to reduce greenhouse gasemissions by 35% of current levels by the year 2025. Inorder to pass, the bill requires a 2/3 majority. Studentsare placed into interest groups and instructed to play therole of a member of their group to the best of their ability.The voting groups are: Climate Scientists,Environmental Advocates, Citizen Advocates, FossilFuel Industry Lobbyists, Future Technology Lobbyists,and Politicians. Two additional groups that do not votebut have a major stake in the results are an Organizationof Small Island Nations and an Organization ofIndustrializing Nations. Students are given a briefdescription of the specific concerns for their group tohelp them prepare. They are also assigned the ThePhysical Science Summary for Policy Makers from theIPCC report (IPCC, 2007) as reading. Students areadvised to find and review additional materials to helpthem best prepare. Grading is based on the collectiveeffort of their group in the exercise as well as individualeffort in their written response to a reading used inpreparation for the exercise.

During the first session of the exercise the studentsmust first hand in a response to the assigned reading astheir "ticket" to the Convention. Students are instructedto produce a short statement that clearly articulates theircurrent voting position and gives a rationale. They workin their groups for 15-20 minutes to draft the positionstatement and then elect one or two spokespersons torepresent them during the Convention. Each group gets2-3 minutes to make a brief statement of their position onthe bill along with an additional 2-3 minutes to fieldquestions and comments on their position statement.During the second session of the exercise, the studentsare given the first 20-25 minutes to reconvene with theirgroup and to lobby other groups. Each group then gets to make a final statement and respond to comments beforevoting on the bill.

Students are engaged in this exercise. They discussand debate how to best represent their position withintheir individual groups and they attempt to lobby themembers of other groups. When speakers make theirgroups' position statements they are often creative inportraying their role. In the commenting period thatfollows, students are eager to challenge those withopposing positions using information they havegathered through personal research. During the secondsession, the classroom is highly active with studentsattempting to persuade their peers in other groups.

ASSESSMENTStudent achievement of the overarching course goals and the ultimate success of the course are assessed with threedifferent measurement tools: a laboratory final project,an essay on the final examination, and most recently theuse of student knowledge surveys. Knowledge surveys(KS) are a set of questions that cover the entire content ofa course and are designed to evaluate student masteryfrom basic knowledge to higher levels of thinking(Nuhfer, 1993; Nuhfer and Knipp, 2003). The KS is notintended to replace exams nor is it graded beyond"complete" or "incomplete". Instead it is one of several


Figure 3. Portion of an ERC course final projectwritten by a pair of students describing thepaleoclimate history of MIACland. Students use avariety of geologic evidence to summarize key eventsand place them in chronological order.

measures that I use as an evaluation of individualstudent learning and as an assessment of the course itself. In a sense the knowledge survey provides a measure of astudent's perception of their own knowledge prior totaking the course and again at the end of the course. Prior to the start of the semester I produced a set of 150questions that I wanted all students to be able to answerby the end of the course. In order to effectively developboth lower and higher order thinking these questionsspan all six levels of Bloom's taxonomy of learning in thecognitive domain (Bloom, 1956). The key to a KS is thatrather than attempting to answer the questions, studentsare asked to rank, on a 3-point scale (where 1 = notconfident, 2 = 50% confident, and 3 = confident), how

confident they are that they could answer each questionon a graded exam. Specifically, students were asked to:

• Mark "confident" as your response if you feel confident that you can now answer the question sufficiently forgraded test purposes.

• Mark "50% confident" as your response if you can nowanswer at least 50% of it or if you know preciselywhere you could quickly get the information neededand could return here in 20 minutes or less to provide a complete answer for graded test purposes.

• Mark "not confident" as your response to the questionif you are not confident that you could adequatelyanswer the question for graded test purposes at thistime.


Reading Student Response

"The Two Mile Time Machine" (Alley, 2001)

"My overwhelming reaction to the final three chapters in the book 'Two Mile TimeMachine' by Richard Alley is a feeling of uncertainty…Global warming is clearly an issuethat humans are definitely contributing to. The problem is though that we do not reallyknow for sure what the extent of our contributions (though clearly major) are or what ourcontributions might result in. This has been my whole problem with global climate change all along, it comes with no concrete answers."

"The Two Mile Time Machine" (Alley, 2001)

"Anyway, the point I wanted to make was that I recently read an article that demonstratesthat even if you were able to create the algal blooms that were desired, and that carbonwere to be used, the ocean has such an efficient system that the algae would be eaten byherbivores, and the carbon would thereby be respired back into the atmosphere with nonet loss of atmospheric carbon."

"The Truth About Denial"(Begley, 2007)

"Overall, it was an interesting read, but I believe the facts should have the final say, andfacts seem to be saying, in an overwhelming fashion, that climate change is a reality and is something the needs to be dealt with."


"It is clear from this article and the article written by Fred Singer that the dividing linebetween parties surrounds the effects that change might have on industry. I think that it is hard to not accept the fact that humans have significantly contributed to the increase ofCO2, methane, and CFC's."


"It is very embarrassing to see the lack of Americans who think that the earth is warmingdue to human influence. I think it is so obvious just by reading the IPCC that we have aneffect on climate…"

Table 4. Examples of student responses to two assigned readings on climate change.

Student Final Exam Essay Response

A

"Humans are contributing to global warming by a manipulation of the greenhouse effect. Activitiessuch as agriculture, cattle farming, aerosol sprays, driving cars,… are taking carbon from reservoirsdeep in the Earth that have been formed over 100s to 1000s of millions of years and humans arepumping that stored carbon into the atmosphere by several Gigatons per year! The greenhouse gasesthat buildup in the atmosphere allow shortwave incoming radiation to pass but then stop outgoinglongwave radiation from leaving."

B"Humans have burned an extremely enormous amount of coal and gas over the past 100 years in orderto improve our quality of life. … CO2 particulates in the atmosphere have risen from 317 ppm in ~1900to 382 ppm in present day. With this rise in CO2 in the atmosphere worldwide, the average globaltemperature has risen .76° C over that same time period."

C"One source of uncertainty is in the possible feedbacks. These aren't completely understood, so theremay be feedbacks that increase the effects of global warming and those that decrease the effects, so anymodel you make has potential error on either side."

D

"Based on evidence from the Greenland Ice Cores we are very certain that it will not change in a linearfashion. We saw in the ice cores that in the past there have been erratic changes from warm to coolclimates. Only recently has the climate become somewhat stable and even now it isn't linear. It is morethan certain that by adversely changing the climate so rapidly that we could 'push the drunk' and putourselves back into the erratic pattern of glaciations and interglaciations."

Table 5. Examples of student responses to a final exam essay question in which students must respond toa climate change skeptic's statement that human influences on climate are minimal. Specifically thestudents respond to the following four questions: 1) Do humans contribute to global warming, and if so,how? 2) What are two strong examples of scientific evidence that humans are likely playing a big role inglobal warming over the past century? 3) Why do estimates of climate change vary so much (i.e. why isthere so much uncertainty)? 4) Based on past records of climate should we expect climate to change in agradual (i.e. linear) fashion? Why or why not?

In the first lecture I explained what I was attemptingto do with the KS, how it might be of benefit to them (as astudy tool and for test preparation), and discussed whatit means to learn. Students completed the KS during thefirst week of classes ("precourse") and again during thelast week of classes, prior to the final exam ("prefinal"). I evaluate student achievement of overarching goals 1and 2 using their performance on the lab final projectdescribed in the previous section. . Student average andmedian scores over five years have consistently fallenbetween the "Satisfactory and Excellent" ranges (avg.scores range between 81 - 89 points, n = 306 students)based on the grading rubric (Table 3). Many studentsreally shine on this project, producing detailed,well-written, and well-supported project reports while asmaller group of students significantly misses the mark. I measure student success in achieving the third goalbased on their performance on a final exam essayquestion that has been used in each course offering.Students must respond to the statement of a climatechange skeptic in a substantive fashion, based on whatthey have learned in the course and from their readingand our discussion of the data and findings from themost recent IPCC Report. I have generally beenimpressed with the level of knowledge that studentsdisplay in their essays (Table 5) and their gradesdemonstrate that most students are performing at a very

good level (B/B+ average for n= 306 students). In theirfinal essays, students rarely express misconceptionsabout climate change that are more commonly made inthe first week of the course (Table 1). Instead, theyconsistently cite relevant data.

Responses to the KS questions serve as an additionalmeasure of student learning, because they can bemapped back to each of the three overarching coursegoals. Some of the key results are shown in Table 6 anddemonstrate that students' perception of what they areable to do changes significantly by the end of the course.Student prefinal responses to KS questions linked to each of the overarching course goals consistently increase byat least one point on the 3-point scale from precoursescores. Most of their responses to questions on the HeatIsland project linked to course goal 1 and those oninterpreting paleoclimate data (pollen, oxygen isotopic)linked to course goal 2 show an increase of 1.5 points.

Full precourse-prefinal results of the KS are shownby question in Figure 4. The average precourse score was1.38 while the average prefinal score was 2.55 showing again of more than one point on the 3-point scale. Overall,the KS data are a powerful indicator of the knowledgethe students perceive that they have gained in the course. The final three questions on the ERC knowledge surveyare about students' confidence in their ability to achievethe overarching course goals. The gains from the


Figure 4. Area plot of the Fall 07 ERC knowledge survey results showing average precourse and prefinalstudent confidence levels by question.

precourse to postcourse surveys were similar to theresults for the survey overall (Table 6).

CONCLUDING THOUGHTSBased on the assessment results for ERC, I have beensatisfied that most of the students taking the course have

achieved the overarching goals or made significantprogress towards them. I do not believe that all coursesthat are offered at intermediate or advanced levels can be successfully offered as an introductory level course. Forexample, the required quantitative skills in ageochemistry course are simply too high for many of thestudents. Indeed, one disadvantage of offering ERC at


Knowledge Survey Question CourseGoal

BloomLevel(1-6)

Precourse class

average(n=56)

Prefinalclass

average(n=56)

Analyze modern and past climate data from the internet, makelogical interpretations, and draw comparisons between differentdata sets

1 5 1.53 2.59

What is albedo? Which surfaces have high, low, and moderatealbedos? 1 1 1.16 2.93

Define the term heat capacity. 1 1 1.70 2.67Discuss the cause of seasonal cycles and long-term trends in theamount of CO2 in the atmosphere as shown in the Keeling datacollected at Mauna Loa.

1 2 1.12 1.91

Explain why Minneapolis, MN has a much greater temperaturerange than San Francisco, CA. 1 4 1.95 2.66

Summarize the factors that contribute to the development of urbanheat islands and the time of day during which heat island intensity isgreatest.

1 2 1.33 2.88

Design an experiment to test for the presence of a heat island thatyou will perform in the twin cities. 1 5 1.26 2.86

Explain why UST might not be the best place to test for evidence ofan urban heat island. 1 4 1.82 2.89

Interpret the geological and past climate conditions of a givenregion using rock types, fossils, pollen, and geochemical data 2 4 1.16 2.57

Compare "relative" and "absolute" time. 2 2 1.72 2.50Given the ratio of daughter to parent isotopic material and a decayconstant, calculate the numerical (radiometric) age of a rock sample. 2 3 1.11 2.14

What is a climate archive and what are some types of archives thatare used to reconstruct past climates? 2 1 1.21 2.63

Given a sequence of sediments consisting (from bottom to top) ofsandstone, limestone, and shale, describe the changes in depositionalenvironments and sea-level.

2 4 1.16 2.70

Interpret oxygen isotopic data and classify glaciations andinterglaciations and identify long-term trends in past oceantemperatures.

2 3 1.04 2.57

Identify glacial till, glacial erratics, and striations. 2 1 1.09 2.75Analyze pollen and sediment data from a lake core to determine pastclimate changes. 2 3 1.05 2.59

Make informed evaluations of climate-related arguments andinformation in the primary scientific literature and mainstreammedia

3 5 1.42 2.57

Evaluate the argument some scientists have made that globalwarming is not caused by humans. 3 5 1.53 2.71

Global temperatures have clearly been warming, but what data givethe best evidence that humans have been responsible for thewarming?

3 4 1.77 2.82

It is believed that there will also be economic benefits of warming inthe Arctic. Compare the potential benefits to the negative effects,which would you expect to be greater in the long term (say 100 years) and why?

3 4 1.46 2.46

What is the range of uncertainty for future warming and why is there uncertainty? 3 2 1.40 2.61

Table 6. Selected Fall 2007 ERC knowledge survey questions and results showing the overarching coursegoal (1-3) that each question is linked to, the Bloom level (1 to 6 with 6 being the highest order thinking),and the precourse and prefinal class average scores.

the introductory level is that an in-depth quantitativeanalysis of climate data or research, which might bepossible in advanced level courses, is not realistic. Themost frequent concerns students have in this courseinvolve having to make mathematical calculations and

students expressed the lowest level of confidence on theBloom level 3 questions (prefinal class average = 2.30),most of which involved making a calculation or usingquantitative reasoning. This means that students withgreater interests in climate that might like to do moreadvanced work might miss the opportunity of anupper-level course does not exist. Choosing anappropriate textbook for ERC has been a minor issue. Ihave used the textbook, Earth's Climate Past and Future,(Ruddiman, 2001). This text is both thorough andwell-written, but a fair amount of the material in the book is aimed at an intermediate or even advanced level soappropriate reading must be carefully selected. As far asI know, there are no other paleoclimatology texts that areintro-level appropriate at this time. A more pressingissue is students' progression into our intermediatecourses. The ERC course is significantly different fromour other introductory courses, and although we doexamine most of the critical concepts that are normallyexpected in such a course, there is less emphasis ontectonic processes (earthquakes and volcanism) andstructural geology and more on surface processes andimportant climate and biogeochemical cycles than in anyof our other intro courses. Students who move from theERC course into some of the intermediate geologycourses may face a steeper learning curve on someconcepts. For example, a student who has taken ourIntroduction to Physical Geology course is more likely tobe comfortable with different types of faults, folds, andother structural features found on geologic maps than


Positive Comments Negative Comments

I think of all the classes I have taken, I learned the most inthis one.

Most topics were very interesting but it would be moreinteresting and easier to retain material if we could relatethe climate of MN into lecture. Lab did an excellent job ofthis

I'm not a science lover, but I really got into a lot of thematerial in this course. I'm glad I took this over any otherscience course.

This course was alright. I felt that there was a lot of materialto know… I felt that it was a bit too much for a 100 levelcourse.

I really enjoyed this course and found most of the subjectmatter very interesting- I wish I would have taken thiscourse earlier in my college career-I would have pursuedgeology further.

Online notes were great, but maybe being posted beforeclass would help.

This course was extremely interesting. I've recommended itto a lot of people. I didn't think I could ever be interested inscience but this course proved me wrong. Everythingcovered was interesting and field trips were fun!

At times the course was slow and confusing. Perhapsanother intro science course should be required so thestudent can understand the material better (isotopes,chemical, etc.)

I have learned an incredible amount this semester andcontinue to be fascinated by the content of this course. I aminspired to continue to think more critically on issues suchas climate

Too much group work. The room is not conducive to groupwork.

This class was very informative and I enjoyed learningeverything a lot. The class has a lot of valuable informationpertaining to what is happening now and I wouldencourage most people to take the course.

Very in-depth lab sessions for a general requirement.

This course was very challenging for me. It was a lot harderthan I expected it to be. I've worked hard, and although Imight not come out with an A+ I feel that I learned a lot.

Very interesting, though a little controversial. Sometimes abit over the head of the everyday Business major, Educationmajor, etc… I found some parts very interesting, others not.But this is a reflection of my interests too. The course didmake me think a lot more about the global warming issue. Ihope we can work together to fix the problem. Thank youfor that!

Table 7. Representative positive and negative student comments from their institutional Student Reportson Teaching from four offerings of ERC.

Introduction to PhysicalGeology: GEOL 111(Semester, year, and # ofstudents responding)

Course rating:“Considering everything,how would you rate thiscourse?” (1-5, 5 is best)

Spring 2005 n=46 3.57Spring 2006 n=55 3.65

Fall 2006 n=77 3.68Earth’s Record of Climate: GEOL 113 (Semester,year, and # of studentsresponding)

Course rating:“Considering everything,how would you rate thiscourse?” (1-5, 5 is best)

Fall 2003 n=31 3.90Fall 2004 n=62 3.79Fall 2005 n=50 3.88

Spring 2007 n=56 3.91

Table 8. Average numerical ratings for three offeringsof Introduction to Physical Geology (GEOL 111) andfour offerings of The Earth's Record of Climate (GEOL113) taught by the author. For both courses, studentsresponded to the question, "Considering everything,how would you rate this course overall", on a 5-pointscale with 5 being the best score.

those who take ERC. I have seen this most clearly in ourdepartment's field course which many students takeright after completing their introductory courseprerequisite. This hasn't hurt the success of thesestudents, but it does require that we keep track of them in case they need further attention in specific areas. There isno reason why greater emphasis on structural conceptscannot be incorporated into this course, and I amworking on improving this for future offerings.

Student comments from their institutional reports on teaching are generally quite positive (Table 7). Themesthat have emerged from these comments suggest thatstudents find the course material to be informative,relevant, and challenging. Several students whopreviously had little interest in science or had notconsidered science in their academic plans comment thatthey are surprised by their positive experience in thecourse. Students with a less positive reaction to thecourse often note that they feel too much is expected ofthem for an introductory course. Interestingly, studentnumerical ratings of the ERC course are consistentlyhigher (by ~5% on average) than those for a moretraditional Introduction to Physical Geology course that I have taught several times using active and inquiry-based techniques (Table 8). Grades are an unlikely reason forthe difference in ratings as there is no significantdifference in the final grade for each course (<1%difference on average). Rather, I suspect that thedifference in student ratings reflects the power of thefocus on climate--and that student feedback isconfirming that we are achieving our departmental goalof providing course material that they find relevant totheir lives.

ACKNOWLEDGMENTSI would like to thank conveners and participants in theNSF-supported On the Cutting Edge Summer 2003Course Development Workshop. Ideas that were sharedat this workshop contributed to the development andsuccess of the ERC course. Thanks to Tom Hickson of theUniversity of St. Thomas, as well as Ed Nuhfer of theCalifornia State University Channel Islands, and ananonymous reviewer for their thorough reviews andcomments which improved this manuscript from anearlier version. REFERENCES

Alley, R.B., 2000, The Two-Mile Time Machine, NewJersey, Princeton Univ., 291 p.

Ahrens, C.D., 2007, Meteorology Today: An Introduction to Weather, Climate, and the Environment (8th ed.),Stamford, Brooks/Cole, 624 p. Apedoe, X.S., Walker, S.E., and Reeves, T.C., 2006, Integratinginquiry-based learning into undergraduate geology,Journal of Geoscience Education, v. 54, p. 414-421.

Bloom, B.S., 1956, Taxonomy of Educational Objectives,the Classification of Educational Goals - Handbook I. Cognitive Domain, New York, McKay.

George, L.A. and Becker, W.G., 2003, Investigating theurban heat island effect with a collaborative inquiryproject, Journal of Geoscience Education, v. 51, p.237-243.

Jauregui, E., 1997, Heat island development in MexicoCity, Atmospheric Environment, v. 31, p. 3821-3831.

Haury, D.H., 1993, Teaching science through inquiry,ERIC Clearinghouse for Science Math andEnvironmental Education, http://www.ericdigests.org/1993/inquiry.htm

Mills, 2004, The urban canopy layer heat island IAUCteaching resources, http://www.urban-climate.org/

Intergovernmental Panel on Climate Change, 2007, In:Solomon, S., Qin, D., Manning, M., Chen, Z.,Marquis, M., Averyt, K.B., Tignor, M., and Miller,H.L., editors. Summary for Policymakers, ClimateChange 2007: The Physical Science Basis.Contribution of Working Group I to the FourthAssessment Report of the Intergovernmental Panelon Climate Change, Cambridge, United Kingdom,Cambridge Press, p. 1-18.

Ireton, M.F.W., Manduca, C.A., and Mogk, D.W., 1997,Shaping the Future of Undergraduate Earth ScienceEducation: Innovation and Change Using an EarthSystem Approach, http://www.agu.org/sci_soc/spheres/

MacDonald R.H., Manduca, C.A., Mogk, D.W., andTewksbury, B.J., 2005, Teaching methods inundergraduate geoscience courses: Results of the2004 On the Cutting Edge survey of U.S. faculty,Journal of Geoscience Education v. 53, p. 237-252.

Nuhfer, E., 1993, Bottom-line disclosure and assessment,v. 7, p. 8.

Nuhfer, E.B., and Knipp, D., 2003, The knowledgesurvey: a tool for all reasons, To Improve theAcademy, v. 21, p. 59-78.

Ruddiman, W.F., 2001, Earth's Climate Past and Future,New York, W.H. Freeman and Co., 465 p.

Schweizer, D.M., Kelly, G.J., 2005, An investigation ofstudent learning in a global warming debate, Journal of Geoscience Education, v. 53, p. 75-84.

Tewksbury, B.J. and MacDonald, R.H., 2005, OnlineCourse Design Tutorial, http://serc.carleton.edu/NAGTWorkshops/careerprep/teaching/design_overview.html


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