Natural Hazards: Never Turn Your Back on Mother Earth

Virtual Field Trip

Geohazards - Earthquakes, Landslides, Tsunami

New Zealand sits on the boundary between the moving Pacific and Indo-Australian Plate. This virtual field trip allows students to explore some of New Zealand's geologically active areas in the Marlborough region. Experts take learners to remote locations in order to understand what causes natural disasters such as earthquakes, landslides and tsunamis. They also learn about risk management associated with these types of geohazards.

The American Geosciences Institute (AGI) video, Big Idea 8: Natural Hazards pose risks to humans, from the Earth Science Literacy Principles collection, introduces natural hazards and examines how they impact humans. It provides an introduction containing useful images and video footage of multiple types of natural hazards. The video also stresses the contributions that geoscientists make to the study of the processes responsible for natural hazards, as well as how we can prepare for them and mitigate their effects. Students can keep a running list of the types of natural hazards to be shared as a group post-video, or a set of guiding questions can be provided to students to consider while they view the video and follow with a class discussion. The main link found at Earth Science Literacy Principles allows for download or for YouTube play.

*The earthquake is the first example of a natural hazard addressed in the unit. Most students should have learned the basics of plate tectonics prior to this unit, however, a review may be helpful. Teachers can visit the IRIS Education and Public Outreach portal to read information about earthquakes and seismology before implementing earthquake activities with their students. IRIS has a wealth of excellent information, including Educational Fact Sheets ("One-pagers") downloadable in English and Spanish, animations, short video lectures, and seismic wave visualizations and sonnifications. These resources will help bring the topic to life in the classroom.

The second activity is an exploration of the IRIS Rapid Earthquake Viewer (REV), an online tool that provides students access to authentic seismic data via two main options. The "Earthquake View" provides seismograms of notable earthquakes dating from the present back to 1989. One may select an earthquake from a list or map, or one may go directly to the five most recent earthquakes by using the list on the left. The "Station View" allows one to view the last 24 hours of ground motion from seismograph stations all over the globe, including those in their local area. It is recommended that students and teachers review the REV glossary which includes definitions of essential terms such as distance degrees, geocentric angles, and focus.

Once students have mastered REV, introduce IRIS Seismic Monitor. This is an interactive display of global seismicity that allows users to monitor earthquakes in near real-time, view records of ground motion, and visit seismic stations around the world. Seismic Monitor shows earthquakes as colored circles, with the size of the circle relating to the magnitude of the quake. Click on the world map to open a zoom map for the region selected. From that window, one can click in the center of the representative earthquake circles to get a list of recent earthquakes in that vicinity, or click on observations stations to bring up station information pages. From the activity page there is a link to the IRIS Earthquake Browser, IEB, which allows users to plot earthquakes on a global or regional map that occurred over a given time period, or that are within a selected magnitude range. The data archive of 3.4 million quakes covers a period from 1970 to just minutes ago. Another feature of IEB is that it allows one to rotate quakes in three dimensions.

*It is highly recommended teachers demonstrate the Monitor and IEB tools in the classroom highlighting key features. (A series of seismology fact sheets provides a helpful overview for teachers if needed.) Be sure to emphasize patterns that emerge in the data such as the correspondence between most earthquake locations over time and tectonic plate boundaries. After the class demonstration, encourage students to engage in structured exploration; we suggest developing a set of specific tasks for students to carry out as they explore.

To understand where earthquakes are likely to occur, it is important to know how to locate their epicenter. In Seismology S-P Earthquake Location, students model the transmission of seismic data from a simulated earthquake, and then use the data they generate to locate the epicenter of the simulated earthquake by triangulation. Before implementing the activity, teachers must review with their students the different types of seismic waves and their motion through Earth. An elongated spring may be used to demonstrate seismic waves. Teachers should also review IRIS Educational Fact Sheet No. 6, How are Earthquakes Located?, before the activity. This "Fact Sheet" may be printed and distributed to students to read as an out-of-class assignment.

The Seismology S-P Earthquake Location "Walk – Run" method requires an "open space" of about 30 x 30 meters—a playfield or a gymnasium. Teachers must have students who are P waves (runners) and S waves (walkers) practice beforehand to ensure that they maintain the same pace during the earthquake simulation. Results will be skewed if teachers do not follow the directions when implementing the activity.

After students have modeled earthquake location with the "Walk-Run" approach, they will then use authentic, recent, three-component seismic data to locate a global earthquake in the next activity Locating an Earthquake with Recent Seismic Data. By the end of this activity, students will be able to identify P and S waves on seismograms, determine the distance of an epicenter from a seismic station using travel time curves, locate the epicenter of an earthquake by triangulation, and
 calculate the time of origin of an earthquake based on seismic data. We recommend that teachers download seismograms and maps from the website in advance and assemble these and other required materials in a student packet.

*Large and sometimes devastating earthquakes can occur without warning. IRIS "Teachable Moments" is a collection of PowerPoint presentations covering recent events compiled by seismologists and education experts within hours of a large earthquake. They are available for educators to download to teach about the event.

*Earthquakes that occur offshore can trigger tsunamis. On March 11, 2011, a magnitude 9 megathrust earthquake off the coast of Japan triggered a large tsunami, with wave heights reaching up to 10 meters. These two events caused widespread devastation and destruction in Japan, washing away entire cities as well as damaging the country's nuclear power plants leading to a potential meltdown of the Fukushima Daiichi Nuclear Plant. SERC has a large collection of visualizations, news articles, and teaching activities for the 2011 Japan earthquake and tsunami.

After the devastating 2004 Indian Ocean and 2011 Japan tsunamis, vulnerable coastal countries became concerned about the potential threat of tsunami destruction. In this chapter of the Earth Exploration Toolbook, Tsunami Run-up Prediction for Seaside, Oregon with ArcExplorer GIS, students identify the potential consequences of a five, fifteen, and twenty-meter sea level rise due to a tsunami run-up on the Oregon coast near the town of Seaside. They use Geobrain Online Analysis System (GeOnAS) to access, view, and process digital elevation model (DEM) data. This DEM data is then imported into Arc Explorer Java Edition (AEJEE) in order to visualize the potential sea-level rise that could occur during a tsunami run-up event near Seaside, Oregon. In AEJEE, the DEM contours will be overlaid with additional geographic data, such as roads and schools, allowing students to see the potential impact of a tsunami event on transportation, infrastructure, housing, and natural habitat in this region. Once they have evaluated the region of potential inundation with My World GIS, students plan evacuation routes for two schools in the town of Seaside. We recommend that teachers download the datasets and AEJEE project files ahead of time. After completing this chapter, students are able to use geospatial data to investigate coastal topography, use AEJEE for predicting sea-level rise during a potential tsunami event, and conduct spatial analyses in order to generate an evacuation management plan.

*A good discussion on volcanoes needs good a geology/geography mini-lesson. This way the students can see how plate movements produce volcanoes as well as get a reminder of where on Earth significant volcanic eruptions have occurred and where volcanoes continue to erupt. Once a bit of a review has taken place the students can then explore how representative types of volcanoes and eruptions can be associated with the different types of plate interactions. A good student map can be found at Active Volcanoes, Plate Tectonics, and the "Ring of Fire". A good teacher review for all things volcanic, including plate tectonics, can be found at Volcanic Ash: Volcanism.

Volcanic Hazards is an excellent activity for introducing the specific vocabulary associated with volcanic eruptions. A jigsaw approach or a graphic organizer for vocabulary would be applicable here.

Smithsonian geologist puts Eyjafjallajökull eruption in perspective is a good discussion of the activity of Iceland's Eyjafjallajökull volcano. It is important to point out the location of the volcano prior to viewing the video. Ms. Cottrell also discusses the effect past major historic volcanoes have had on humans as well as some volcanoes' current threat to our societies.

Climate and Civilization - The Maya Example requires the 2001 BBC video, Ancient Apocalypse - The Maya Collapse, as the hook. There are more recent accounts, but these newer versions do not work as well with the activity. The above link for the documentary is the YouTube site as the video links found in "General Information for Teachers" are nonfunctional. It is important to set the stage for the activity by showing the first 20 minutes of the video to the class.

After students have watched the video, ask students to comment on the hypothesis that drought may have contributed to the collapse of the Mayan civilization and to suggest other possible causes. Next, have students do the activity. When they have completed it, return to the hypothesis of drought as the cause for Mayan population decline and conduct a class discussion. Some students will accept that the evidence provided by the activity supports the hypothesis; others will cite the need for additional evidence, creating opportunities to discuss different types of proxy climate data. Still others will remain unconvinced.

After the class discussion, watch the last part of the video, from 36 minutes to the end, and be sure to leave extra time for additional discussion about the very real threat of drought in the southwest and western United States. The documentary is key to the success of this activity. If YouTube is unavailable in the classroom, then we recommend buying the video. (The instructions for using Excel are out-of-date.)

The EarthLabs Hurricanes module has 9 lab investigations. We recommend Labs 2 and 9. Lab 2: Hurricane Anatomy provides a number of visuals to enable the student to characterize hurricanes and analyze those characteristics in order to make comparisons. The students will need computers and internet access. Lab 9: Death and Destruction begins with students exploring the results of hurricanes both in terms of causes of human casualties and property losses. A hands-on activity has the students creating a model of storm surge. An inquiry based lab could be done with the students hypothesizing and testing the different variables given in order to create different effects of a storm surge.

*If students are studying hurricanes during hurricane season, they can monitor the position and status of storms in real time. Hurricanes can serve as an exciting entry point into understanding everyday weather, or a culminating topic for an Earth systems or environmental science unit.