A Year in the Life of the Earth SystemThe lab activity described here was adapted by Erin Bardar of TERC for the EarthLabs project.
Summary and Learning Objectives
Students have been examining Earth as a system of interacting parts, initially from the local perspective but more recently from the regional and global perspectives. In order to fully understand the Earth as a system and how its components interact with each other, students need to consider change over time. On relatively short times scales, these changes are related to the fact that the solar energy that drives the Earth system passes through an atmosphere that varies across space and time before reaching a spinning sphere. Across longer seasonal and annual time scales, these changes are more specifically related to the differential heating that results from the tilt of Earth's axis and Earth's orbit around the sun. At this longer-term global scale, it may be easier to see the repeating patterns of change across space and time and to infer how changes in one sphere may be linked to changes in others.
After completing this investigation, students should be able to:
- use ImageJ to animate monthly maps of Earth system components;
- find patterns and connections between and among maps containing different environmental data; and
- understand the relationship between time and space with regard to global environmental data.
Activity Overview and Teaching MaterialsIn Part A: Students use ImageJ, a free image processing tool, to make an animation of monthly data maps for one component of the Earth system in order to explore how the Earth changes over time at the global scale.
In Part B: Students make an animation of two datasets side by side to investigate relationships between different components of the Earth system across a 12-month period.
Printable MaterialsTo download one of the PDF or Word files below, right-click (control-click on a Mac) the link and choose "Save File As" or "Save Link As."
- Stop and Think Questions (PDF (Acrobat (PDF) 36kB Sep13 10) and Word (Microsoft Word 2007 (.docx) 21kB Aug7 18))
- You may also decide to print and distribute to students some of the resources in the Background Information section below.
Teaching Notes and Tips
ImageJ is free public domain image processing software developed at the National Institutes of Health. Its power and flexibility allow it to be used as a research tool by scientists in many disciplines, from medicine to astronomy. Installers are available for Windows, MacOS and OSX, and Linux.
You can use ImageJ to display, annotate, edit, calibrate, measure, analyze, process, print, and save raster (row and column) image data (TIFF, GIF, JPEG, and many others). It reads most common raster image formats as well as raw data files in text format, such as from spreadsheets. ImageJ also supports stacks - multiple images in a single window - for animation and analysis.
To Download and Install ImageJ:
Go to the ImageJ Download page , and download and install the application for your operating system.
Click the ImageJ Download page and it will open in a new window. Click the link that appears directly below the name of your computer's operating system (e.g. Mac, Linux, Windows). This action will transfer a compressed file of the software to your computer. Your browser should automatically expand the file, creating an ImageJ folder on your computer's hard drive.
For more details, or if you have problems running the application, access ImageJ's Installation Instructions then select your operating system.
Updating ImageJ Software
Double-click the ImageJ icon to launch the application and choose Help > Update ImageJ.... A window will appear, telling you the version you are currently running and a list of upgrade versions. Choose the version you want to upgrade to (usually the most recent, or default version) and click OK. After the update downloads, re-launch ImageJ to run the new version. NOTE: Some users have reported problems updating ImageJ in certain versions of Windows. To fix this problem, you will need to manually update ImageJ.
- Right-click the link at right to download the ij.jar file. Be sure to save it as simply ij.jar. ij.jar (Jar Archive 1.4MB Feb8 10)
- When prompted where to save the file, navigate to the ImageJ folder and save the file there. Replace the existing ij.jar file.
- For most installations, the ImageJ folder will be in the Program Files directory on your hard drive. The path to the ImageJ folder is c:\Program Files\ImageJ.
The ImageJ Toolbar
The ImageJ toolbar contains both built-in and customized tools for manipulating images. Most of the tools are similar to those used in other graphics programs.
Running the Animations
The animations that students observe in this Lab are powerful, but trying to take in a summary of constantly changing data for the whole planet across a full year is a challenge, and looking for relationships between two such massive data sets is even more challenging. To help students with these challenges, slow down the animations. Have them open the Animations Options window in ImageJ (Image > Stacks > Tools > Animation Options...) and set the speed at no more than .4 or .5 fps (Frames per Second).
Something else that can help students notice change is, when using the manual animation controls (forward and back arrows below the images) move back and forth between just two images at a time. Doing this helps one notice the changes between images, and allows one to focus on specific parts of the planet for a period of time.
You can assess student understanding of topics addressed in this Investigation by grading their responses to the Stop and Think questions.
State and National Science Teaching Standards
(1) Scientific processes. The student conducts laboratory and field investigations for at least 40% of instructional time using safe, environmentally appropriate, and ethical practices. The student is expected to:
(2) Scientific processes. The student uses scientific methods during laboratory and field investigations. The student is expected to:
(A) demonstrate safe practices during laboratory and field investigations.
(E) demonstrate the use of course equipment, techniques, and procedures, including computers and web-based computer applications;
(F) use a wide variety of additional course apparatuses, equipment, techniques, and procedures as appropriate such as satellite imagery and other remote sensing data, Geographic Information Systems (GIS), Global Positioning System (GPS), scientific probes, microscopes, telescopes, modern video and image libraries, weather stations, fossil and rock kits, bar magnets, coiled springs, wave simulators, tectonic plate models, and planetary globes;
(G) organize, analyze, evaluate, make inferences, and predict trends from data;
(I) communicate valid conclusions supported by data using several formats such as technical reports, lab reports, labeled drawings, graphic organizers, journals, presentations, and technical posters.
(3) Scientific processes. The student uses critical thinking, scientific reasoning, and problem solving to make informed decisions within and outside the classroom. The student is expected to:
(A) in all fields of science, analyze, evaluate, and critique scientific explanations by using empirical evidence, logical reasoning, and experimental and observational testing, including examining all sides of scientific evidence of those scientific explanations, so as to encourage critical thinking by the student;
(B) communicate and apply scientific information extracted from various sources such as current events, news reports, published journal articles, and marketing materials.
(11) Science Concepts. Solid Earth. The student knows that Earth's surface continuously changes over long and short time scales in ways involving dynamic and complex interactions among Earth's subsystems. The student is expected to:
(A) compare the roles of erosion, deposition, and igneous activity by lava, water, wind, ice, and gravity in constantly reshaping Earth's surface;
(C) describe and interpret Earth surface features using a variety of methods including satellite imagery, aerial photography, topographic and geologic maps, and apply appropriate technologies such as Geographic Positioning Satellite (GPS) receivers and Geographic Information Science (GIS) software.
(13) Science concepts. Fluid Earth. The student knows that the Fluid Earth is composed of the hydrosphere and atmosphere subsystems that interact on various time scales with the biosphere and geosphere. The student is expected to:
(14) Science concepts. FluidEarth. The student knows that Earth's global ocean, powered by the Sun, is a major driving force for weather and climate through complex atmospheric interactions. The student is expected to:
(D) discuss mechanisms, such as atmospheric carbon dioxide concentration, major volcanic eruptions, changes in solar luminance, giant meteorite impacts, and human activities that result in significant changes in Earth's climate.
(15) Fluid Earth. The student knows that interactions among Earth's five subsystems influence climate and resource availability, which affect Earth's habitability. The student is expected to:
(C) explain how thermal energy transfer between the ocean and atmosphere drives surface currents, thermohaline currents, and evaporation that influence climate.
(A) describe how changing surface-ocean conditions, including El Niño-Southern Oscillation, affect global weather and climate patterns.
Science as Inquiry (12ASI)
Abilities necessary to do scientific inquiry
12ASI1.3 Use technology and mathematics to improve investigations and communications. A variety of technologies, such as hand tools, measuring instruments, and calculators, should be an integral component of scientific investigations. The use of computers for the collection, analysis, and display of data is also a part of this standard. Mathematics plays an essential role in all aspects of an inquiry. For example, measurement is used for posing questions, formulas are used for developing explanations, and charts and graphs are used for communicating results.
12ASI1.6 Communicate and defend a scientific argument. Students in school science programs should develop the abilities associated with accurate and effective communication. These include writing and following procedures, expressing concepts, reviewing information, summarizing data, using language appropriately, developing diagrams and charts, explaining statistical analysis, speaking clearly and logically, constructing a reasoned argument, and responding appropriately to critical comments.
Earth and Space Science (12DESS)
Energy in the earth system
12DESS1.3 Heating of earth's surface and atmosphere by the sun drives convection within the atmosphere and oceans, producing winds and ocean currents.
12DESS1.4 Global climate is determined by energy transfer from the sun at and near the earth's surface. This energy transfer is influenced by dynamic processes such as cloud cover and the earth's rotation, and static conditions such as the position of mountain ranges and oceans.
12DESS2.2 Movement of matter between reservoirs is driven by the earth's internal and external sources of energy. These movements are often accompanied by a change in the physical and chemical properties of the matter. Carbon, for example, occurs in carbonate rocks such as limestone, in the atmosphere as carbon dioxide gas, in water as dissolved carbon dioxide, and in all organisms as complex molecules that control the chemistry of life.
Use ImageJ to Create Additional Stacks and AnimationsFor this Lab, instructions have been provided for students to download a sequence of images from NEO (for example, 12 consecutive months of a specific variable). Simplified instructions for how to build an animation using any of the images available from the NEO Web site are provided here.
1. Download a sequence of images from NEO (for example, 12 consecutive months of a specific variable) and save them in a folder, giving each a file name that allows you to identify the image date or month name.
2. Open ImageJ and use File > Open to open, in chronological order, each of the images you want to appear in the animation. The images will appear in the animation in the same order in which they were opened. Note: ImageJ will recognize only those images that have been opened using ImageJ > File > Open.
3. Select the menu item Image > Stacks > Images to Stack. ImageJ will "stack' the set of images so that only one is visible, and will prompt you to name and save the newly created stack.
4. Select the menu item Image > Stacks > Tools > Start Animation.
5. To stop the animation select Image > Stacks > Tools > Stop Animation.
6. To change the speed of the animation, go to Image > Stacks > Tools > Animation Options.
If students are unable to download individual images from NEO, stacks of time-sequence images have also been prepared for the year 2009, so all they need to do is download them and open/animate them in ImageJ.
- Solar Insolation/Land Surface Temperature Comparison (TIFF 17.8MB Jul4 10)
- Sea Surface Temperature (SST)/Solar Insolation Comparison (TIFF 17.8MB Jul5 10)
- Vegetation Index (NDVI)/Total Rainfall Comparison (TIFF 17.8MB Jul4 10)
1. Open ImageJ and use File > Open to open the pre-made image stacks.
2. Select the menu item Image > Stacks > Tools > Start Animation.
3. To stop the animation select Image > Stacks > Tools > Stop Animation.
4. To change the speed of the animation, go to Image > Stacks > Tools > Animation Options.
Use ImageJ to Combine Animations
To compare two stacks by running them in the same animation:
1. Open ImageJ and use File > Open to open two stacks.
2. Select the menu item Image > Stacks > Tools > Combine.
3. Use the drop-down menus to select the order (left-right) in which you want the stacks to appear.
4. Name and save the combined stack, and use the menu items described above to start, stop, and modify the speed of the animation.
Going Further: The ImageJ Users Guide
Complete documentation for ImageJ can be found at http://rsbweb.nih.gov/ij/docs/index.html. While the 189-page ImageJ Users Guide, available in both PDF and HTML formats, may seem overwhelming at first glance, it is a well-organized and very usable resource with a detailed Table of Contents and an extensive Index.