ED52A-01
From Basic Physics to Geoscience Applications: Floating Golf Balls and Levitating Magnets
Basic physics principles often play out in interesting ways in geophysical systems. This presentation touches upon two fundamental notions from the physical sciences: the concept of density and the force of magnetism. "Exploring Density with Salt and Fresh Water: Par 5" helps students explore the concept of density by observing the density difference between fresh water and a hypersaline solution, how a less-dense layer of water can remain "afloat" atop a denser layer for extended periods of time, and how an object with a density that is intermediate between that of the two liquids (in this case, a golf ball) can remain suspended at the interface between the liquid layers. This activity serves as a discussion starter for topics such as density-driven ocean circulation and the gradual mixing of fresh and salt water at estuaries where freshwater rivers flow into the sea. "Magnetic Levitation" reminds students of the basic principles of magnetism, and encourages them to explore the concepts of force equilibrium, oscillatory motion, and damping in multiple-degree-of-freedom systems. This basic physical system also serves as a simple model of increasing density with depth in both the atmosphere and the oceans. "Magnetometer Extensions" has students use a simple, inexpensive magnetometer to simulate magnetic prospecting and to explore the symmetric patterns of polarity embedded in the igneous rocks on either side of a mid-ocean spreading ridge. Finally, in "Terrabagga", students use a magnetometer to explore the magnetic fields of planets as though on board a spacecraft during a planetary fly-by.
ED52A-02
Using Satellite Drag to Teach About the Near-Space Environment
Physics students are intrigued by activities in space. To link this natural curiosity with solid problem-solving skills, we have developed a spreadsheet simulation of a satellite moving through an atmosphere of variable density. The simulation-laboratory has been used in US Air Force Academy (USAFA) introductory mechanics classes for several semesters. Variants of this activity have also been used in a USAFA advanced division space physics class, a high school advanced placement physics class, and in the Center for Integrated Space Weather Modeling graduate summer school course. The simulation reviews mechanics and illustrates a method scientists might use to break a complex problem into small, solvable elements. Interactive computational techniques and empirical models are also introduced as tools for analyzing orbital motion. The simulation consists of two linked spreadsheets and their associated plots. One spreadsheet contains density and temperature for the lower 1000 kilometers of the earth's atmosphere, and the other contains the orbit simulation. Students can modify the standard atmospheric temperature profile to learn about the physical link between temperature and density in the upper atmosphere. In advanced division classes we ask students to "modify" the atmospheric temperature profile in order to match the known orbital decay rate of the STARSHINE satellites. Students can confirm that the upper atmosphere is, in fact, cooling even as the lower atmosphere records a recent warming trend. The activities described herein are appropriate for an introductory undergraduate course with laboratory access to personal computers. We will provide a demonstration of the simulation and pre- and post lab evaluations.
ED52A-03
Taking Research on the Road: Modeling the Effects of Dam Removal on the Elwha River
The Science Museum of Minnesota's (SMM) Earthscapes River Restoration classes introduce students to the issues surrounding dam removal, provide context within which to explore data and concepts from National Center for Earth-surface Dynamics (NCED) research, and give students the opportunity to actively participate in ongoing research on river systems. The topics of Dam Removal and River Restoration provide excellent case studies from which to gain an interdisciplinary understanding of the ecological and physical processes that define and shape rivers and river networks. The geomorphic response of rivers to dam removal is extreme and provides a highly dynamic example of a river's natural tendency to move toward quasiequilibrium. Furthermore, the intense social, political, and economic questions and tensions raised by dam removal provide an engaging backdrop against which to explore a current scientific problem. This session will present classroom activities developed for the residency program in which students explore the issues alluded to above. Participants will have a chance to experiment with the classroom-scale dam-removal models developed by NCED researchers and SMM educators and to try out some of the classroom and data collection activities developed to date.
ED52A-04
Educating K-12 Students about Glacier Dynamics in a Changing Climate
Public awareness of climate change is growing in the United States. Popular movies, books and magazines are frequently addressing the issue of global warming - some with careful scientific research, but many with unrealistic statements. Early education about the basic principles and processes of climate change is necessary for the general public to distinguish fact from fiction. The U.S. National Science Foundation's GK-12 program (GK-12; grades K to 12) currently in its sixth year, provides an opportunity for scientific enrichment for students and their teachers at the K-12 level through collaborative pairings with science and engineering graduate students (the Fellows). The NSF GK-12 program at the University of Maine has three goals: to enrich the scientific education of the students by providing role models, expertise, and equipment that may not be accessible otherwise; to provide professional development for the teachers through curriculum enrichment and participation at science conferences; and to improve the teaching and communication skills of the Fellows. The University of Maine is one of over 100 U. S. universities participating in this program. During the 2004-05 academic year, 11 graduate and one undergraduate student Fellows, advised by University faculty members, taught at schools across the state of Maine. Fellows from, biology, earth science, ecology, engineering, food science, forestry, and marine science, and taught in their area of expertise. We created a hands-on activity for middle and high school students that describes glacier mass balance in a changing climate. The students make a glacier using glue, water and detergent ('flubber') and construct a glacier valley using plastic sheeting. Flubber behaves in mechanically similar ways to glacier ice, undergoing plastic deformation at low stresses and exhibiting brittle failure at high stresses. Students are encouraged to run several tests with different values for valley slope, glacier mass, 'flubber' temperature and basal conditions. We compare our glacier models to the dynamics of real glaciers and discuss how and why they might be changing over time. Throughout the activities, we stress the use of the scientific method, a fundamental building block in science education.
ED52A-05
Classroom Demonstration and Interactive Model of Sea-Level Control on Lateral and Vertical Facies Changes
Students often have difficulty understanding and visualizing the role that relative sea-level change plays in controlling vertical and lateral facies changes; they also struggle with explanations of regional facies patterns and changes as sea-level dependant. This interactive, dynamic, in-class model has been developed to build their understanding both of this topic, and of the nature of predictive scientific models. The model can be used as a follow-Up to field observations, or to pre-teach concepts. The model assumes a land-ocean transect that is divided into 5 sedimentary settings. Each setting in the land-ocean transect is associated with sediment grain size that decreases basinward; the most basinward component is carbonate. In the model, seven 10-cm diameter see-through tubes are set up to represent 'cores' spread along the land-ocean transect. Brightly-colored plastic beads are used to represent sediment deposited in each of the sedimentary settings. At the start, the position of the shoreline (sea level) is fixed between the fluvial (tube 2) and beach (tube 3) sediments. Students then deposit beads that represent their sediment type in the each tube. Other students control the sea-level marker, which can be raised or lowered, and students with the sediment (beads) move shoreward or basinward accordingly, and deposit their sediments (beads) in the appropriate tube. This produces a simple visual record (tubes with layers of distinctly colored beads) that show the idealized sedimentary consequences of relative sea-level change. After large-scale patterns in facies changes have been demonstrated and discussed, students can manipulate variables such as supply and rate. Students can fill a basin using a sequence of events they determine, and other student groups can interpret their cores. The learning and approach of this model can be extended to include real sediment (gravel, sand, silt, mud) deposited in cardboard tubes that are then opened and treated as cores; the cores are logged, their distribution mapped, and the record interpreted. Alternatively students can be asked to produce a replica of the stratigraphy in a given area. A higher-level extension includes the use of peel images from the experimental mini-basin developed by the National Center for Earth-surface Dynamics (http://www.nced.umn.edu/Rapid_and_slow_level_changes_XES-96_prototype_basin.html. The variables (supply, sea-level change, basin subsidence) for the experimental mini-basin are known precisely, so a transverse section can be described and interpreted in their context. Sections parallel to shoreline can then be assigned to student groups for them to place in context and interpret. This suite of activities spans the continuum from observation through interpretation, modeling, and prediction.
ED52A-06
Discovering Plate Boundaries, A Data-Rich Inquiry-Based Classroom Exercise for Teaching Plate Tectonic Boundary Processes
Discovering Plate Boundaries is a classroom exercise based on 4 world maps containing earthquake, volcano, topography, and seafloor age data. A novel aspect of the exercise is the jigsaw manner in which student groups access the maps and use them to discover, classify, and describe plate boundary types. The exercise is based only on observation and description, which makes it useful at a wide variety of levels. We have used it successfully with middle school, high school, and college major and non-major earth science classes, as well as with pre-service and in-service teachers. The exercise takes three to four 50 minute class periods to complete and involves the students making presentations to one another in small groups and to the whole class. The students come away from the exercise with knowledge of the key features of each type of plate boundary and a sense of why each looks the way it does. While the materials are accessible on the web (http://terra.rice.edu/plateboundary/ and through http://www.dlese.org ), the actual exercise is not based on student access to the Web and is not dependent on classroom technology equipment.
ED52A-07
Student-centered Experiments on Earthquake Occurrence Using the Seismic/Eruption Program
Seismic/Eruption is a free Windows program that plots the locations of earthquakes and volcanic eruptions through time on maps of the world or various geographical areas. The hypocenter database can be updated via internet to include the NEIC catalog from 1960 to present. Many teaching activities based on this program (e.g. Braile and Braile, 2001) can help students draw conclusions about the distribution and rate of occurrence of earthquakes. In this activity students, individually or in small groups, select a seismically active region of interest and make their own map. They select a time window, perhaps 20 years. By changing the minimum magnitude setting in Seismic/Eruption and replaying the plots, they observe first-hand that large earthquakes occur less often than smaller earthquakes. The total number of earthquakes plotted is easily read from a counter on the screen. Students compile a table of the number of earthquakes per year with magnitude greater or equal to a certain magnitude, using a range of magnitude thresholds. These are then plotted on semi-log paper in the form of a Gutenberg-Richter plot. Connecting the points on the plot allows students to see a linear trend, and to think about why there may be departures from that linear trend for very small and very large magnitudes. If they assume earthquake occurrence is equally distributed in time, they can predict how often an earthquake of a given magnitude is likely to occur in their chosen region. They can also replay Seismic/Eruption to see whether that assumption is valid. Allowing students to interrogate the most accurate, complete and up-to-date earthquake catalog about a region of their own choosing provides ownership of the experiment. Students may choose an area of a recent newsworthy earthquake (e.g. Sumatra), or their family's ancestral region, or an area they are studying in another class. Students should be encouraged to pose questions and hypotheses about earthquake occurrence, knowing that they have the data and a display tool at hand to answer those questions.
ED52A-08
EarthTutor: An Interactive Intelligent Tutoring System for Remote Sensing
Earth science classes in colleges and high schools use a variety of satellite image processing software to teach earth science and remote sensing principles. However, current tutorials for image processing software are often paper-based or lecture-based and do not take advantage of the full potential of the computer context to teach, immerse, and stimulate students. We present EarthTutor, an adaptive, interactive Intelligent Tutoring System (ITS) being built for NASA (National Aeronautics and Space Administration) that is integrated directly with an image processing application. The system aims to foster the use of satellite imagery in classrooms and encourage inquiry-based, hands-on earth science scientific study by providing students with an engaging imagery analysis learning environment. EarthTutor's software is available as a plug-in to ImageJ, a free image processing system developed by the NIH (National Institute of Health). Since it is written in Java, it can be run on almost any platform and also as an applet from the Web. Labs developed for EarthTutor combine lesson content (such as HTML web pages) with interactive activities and questions. In each lab the student learns to measure, calibrate, color, slice, plot and otherwise process and analyze earth science imagery. During the activities, EarthTutor monitors students closely as they work, which allows it to provide immediate feedback that is customized to a particular student's needs. As the student moves through the labs, EarthTutor assesses the student, and tailors the presentation of the content to a student's demonstrated skill level. EarthTutor's adaptive approach is based on emerging Artificial Intelligence (AI) research. Bayesian networks are employed to model a student's proficiency with different earth science and image processing concepts. Agent behaviors are used to track the student's progress through activities and provide guidance when a student encounters difficulty. Through individual feedback and adaptive instruction, EarthTutor aims to offer the benefits of a one-on-one human instructor in a cost-effective, easy-to-Use application. We are currently working with remote sensing experts to develop EarthTutor labs for diverse earth science subjects such as global vegetation, stratospheric ozone, oceanography, polar sea ice and natural hazards. These labs will be packaged with the first public release of EarthTutor in December 2005. Custom labs can be designed with the EarthTutor authoring tool. The tool is basic enough to allow teachers to construct tutorials to fit their classroom's curriculum and locale, but also powerful enough to allow advanced users to create highly-interactive labs. Preliminary results from an ongoing pilot study demonstrate that the EarthTutor system is effective and enjoyable teaching tool, relative to traditional satellite imagery teaching methods.