Phase change—Creation of glaciers and ice shields involves factors associated with change of phase. This is an opportunity to apply concepts like vapor pressure, vaporization and freezing temperature.
Methods of analysis—Chemistry is often about analysis. What are the chemical components of this system? Paleoclimatology allows you to discuss with students various types of chemical analysis discussed in the article.
Isotopes—One of the most important methods of analysis for ice cores is based on the isotopes of oxygen. You can review isotopes or preview them in preparation for discussing this article.
Chemistry and the environment—Take this opportunity to stress with students that it is often chemists who are analyzing ice core components and other proxy data. Also remind students that many chemicals they might study in the course are important in nature.
Compounds—A variety of chemical compounds are important in this article—carbon dioxide, methane, oxygen, carbon monoxide, hydrogen peroxide, etc. Their unique properties are what make them important in the context of this article.
Possible Student Misconceptions (to aid teacher in addressing misconceptions)
“Recent global warming is caused by the sun.”The sun’s energy reaching the earth has been measured for thirty years and it is not increasing. “Satellite observations clearly show the well-known 11-year solar cycle, during which the amount of sunlight reaching the Earth’s surface varies by about 0.1 percent. This cycle causes the global temperature to fluctuate up and down by about 0.2 °F, much less than the observed warming of about 1 °F in the past 50 years. More importantly, the solar cycle causes an up-and-down cycle, not an upward trend similar to the trend in the global temperature. The sun’s output has not increased over the past three decades.”
“The last few years have been cooler, so global warming can't be real.” Some people claim that the planet has entered a cooling phase either since 1998 or since 2005, depending on the data set. However, just because 1998 and 2005 are the two warmest years on record does not mean that a long term warming trend is not continuing. The climate is defined by long-term averages, not the ups and downs that occur every few years. For example, the average temperature for the last five years is higher than for the previous five years, and so on. Even with the variability in global average temperatures, a long-term warming trend remains. The ten warmest years in the 150-year thermometer record have all occurred in the twelve years between 1997 and 2008; thus, none of the previous 15 decades has been as warm on average as the last decade. Even with a short-term pause in warming, the past three years are among the ten hottest years of the past 150.
Anticipating Student Questions (answers to questions students might ask in class)
“How can glaciers exist at a latitude only 4o south of the equator?”Despite the fact that Mt. Kilimanjaro is located in the tropics, you need to remember that as you increase elevation, the temperature decreases. So while the average temperature in the town of Moshi at the base of the mountain is 70-80 oF, the average temperature at Uhuru Peak, the top of the mountain, is 0 to -15 oF, cold enough for ice.
How can they tell how old parts of an ice core are?” That has been a challenge for paleoclimatologists, who have used multiple methods of dating layers of ice cores. The first 1000 m of a core might represent 10,000 years and the next 1000 meters might represent 100,000 years due to the compacting of the ice over so long a time. Knowing when volcanic activity occurred allows scientists to “mark’ a place in the core when the ash from volcanic activity is found. Radioisotope dating has also been used. And scientists know from the ice flow patterns the approximate age of the ice.
In-class Activities (lesson ideas, including labs & demonstrations)
In this activity students use real Antarctic ice core data to learn how scientists learn about climate change from ice cores: http://eesc.columbia.edu/courses/ees/climate/labs/vostok/.
Here is another ice core data activity from the TV show NOVA: http://www.pbs.org/wgbh/nova/teachers/activities/3005_vinson.html.
This activity allows students to plot CO2data from Mauna Loa, Hawaii, and determine rate of increase: http://serc.carleton.edu/introgeo/interactive/examples/co2.html.
You can have students analyze simulated ice cores using an adapted version of the lesson plan found at http://www2.umaine.edu/USITASE/teachers/pdf/Ice%20Cores.pdf . Even though the lesson is aimed at grades 3-6, adding variables to the ice can make it appropriate for older students. For example, in addition to varying the layer thickness you could add, for example, dilute sulfate solution to one or more layers to indicate volcanic activity.
This data activity correlates sea ice and snow depth: http://tea.armadaproject.org/activity/tea_activity_porter_seaice.html.
This lab activity simulates the CO2 analysis of ice cores: http://www.vcapcd.org/AirTheFilm/pubs/CarbonDioxideinIceCoreSamplesLessonPlan.pdf.
You can download a lesson here, http://www.fraserinstitute.org/WorkArea/DownloadAsset.aspx?id=4244, that uses real data to teach students about climate change. This material is very extensive.
The Byrd Polar research Center offers a five-module series of classroom activities about ice cores at http://wosu.org/ice-cores/. Each of the five modules—“Climate and Ice,” “Recovering Ice Cores,” “Calendars in Ice,” “Stories in Ice,” and “Predictions from the Ice”—have multi-media components and lab activities.
Out-of-class Activities and Projects (student research, class projects)
Students could be assigned to read one or more of the entries from this blog, http://kiboice.blogspot.com/, and write a brief summary. The individual summaries could be combined to present a history of this research on Kilimanjaro.
Teams of students can be assigned one of the five sectors on this site from the Pew Center on Global Climate Change and prepare a report for the class: http://www.pewclimate.org/climate-techbook.
If you wish to assign research on ice core climatology, you can use this site from the Ice Core Paleoclimatology Research Group at Ohio State University as a starting point for assigning the research: http://bprc.osu.edu/Icecore/Abstracts/Publications.html.
Students can research timelines based on ice core data and write a report at http://www.pbs.org/wgbh/nova/warnings/stories/.
References (non-Web-based information sources)
Gasse, F. Kilimanjaro’s Secrets Revealed. Science, October 18, 2002, 298, pp 548-549.
Thompson, L. G.; et al.Kilimanjaro Ice Core Records: Evidence of Holocene Climate Change in Tropical Africa. Science, October 18, 2002, 298, pp 589-593.
Krajick, K. Ice Man: Lonnie Thompson Scales the Peaks for Science, Science, October 18, 2002, 298, pp 518-522.
Websites for Additional Information (Web-based information sources)
More sites onice cores You can view a video on ice cores in Antarctica
here: http://www.youtube.com/watch?v=kdfcNIFEnF8 and
here: http://www.youtube.com/watch?v=zoTXbXsC69k&feature=related and
The U.S. National Ice Core Laboratory, part of the U.S. Geologic Survey, has its own web page with a lot of information, at http://nicl.usgs.gov/. NOTE: see this page of links to other ice core projects: http://nicl.usgs.gov/links.htm>
More sites on paleoclimatology
NOAA has an extensive web site on this topic at http://www.ncdc.noaa.gov/paleo/paleo.html.
More sites onclimate change NASA has a web page on climate change with data supporting key indications that climate change is taking place: http://climate.nasa.gov/.
The Intergovernmental Panel on Climate Change, the U.S. blue-ribbon panel, has an extensive web site at http://www.ipcc.ch/.
For a comprehensive report from the EPA on current climate change indicators, see http://www.epa.gov/climatechange/indicators/pdfs/ClimateIndicators_full.pdf.
For a slide show on climate change indicators you can use in class see http://www.epa.gov/climatechange/indicators/pdfs/climate_indicators_slideshow.pdf.
In 2008, the National Academies of Science issued this report on climate change: http://dels-old.nas.edu/dels/rpt_briefs/climate_change_2008_final.pdf.
An extensive web site on climate change can be found at http://www.global-climate-change.org.uk/.
More sites on the contributions of Svante Arrhenius to global warming theory For a biography of Arrhenius from the Nobel Prize site see http://nobelprize.org/nobel_prizes/chemistry/laureates/1903/arrhenius-bio.html.
To read Arrhenius’ 1896 paper in which he first advanced the question of whether the presence of carbon dioxide in the atmosphere contributed to the warming of the atmosphere see http://www.rsc.org/images/Arrhenius1896_tcm18-173546.pdf.
More sites on Mt. Kilimanjaro
To view a video on Mt. Kilimanjaro go to http://wn.com/Mount_Kilimanjaro.
For the U.S. Department of State “Background Notes” on Tanzania, the country in which Kilimanjaro is located, see http://www.state.gov/r/pa/ei/bgn/2843.htm.
More sites onLonnie Thompson For a complete biography of Thompson see http://www.pnas.org/content/103/31/11437.full.
To see a National Geographic interview with Thompson go to
For a five part interview with Thompson see http://wn.com/lonnie_thompson.
The web site for Thompson’s home base, the Byrd Polar Research Center is http://bprc.osu.edu/.