Three-D Visualization: Hands-on Bathymetry and Topography...

Three-D Visualization: Hands-on Bathymetry and Topography Activities

Sheryl Braile, Happy Hollow School

West Lafayette, IN

sjbraile@gmail.com

Larry Braile, Purdue University

West Lafayette, IN braile@purdue.edu,

web.ics.purdue.edu/~braile

CSTA Conference,

October 2015

Sacramento, CA PowerPoint file: http://web.ics.purdue.edu/~braile/new/TopoMaps.pdf

Three-D Visualization: Hands-on Bathymetry and Topography Activities

Importance:

Visualizing in 3-D is difficult for many people.

Textbooks figures and images (PPTs, etc.) are 2-D diagrams or perspective views.

Very important in visualizing very small (microscopic) and very large (Earth, solar system, galaxies, the universe) features.

Introduction to Topographic (Topo) Maps

Topo maps are very accurate, detailed maps of locations in the U.S. and around the world. In the U.S., most topo maps are produced by the U.S. Geological Survey (USGS) and can be purchased, or downloaded for free from the USGS store – see instructions below. Topo maps use contour lines (lines of equal elevation) to show topography. Topo maps are also very useful for teaching the concept of scale.

Two similar illustrations of contour maps (lower images) and corresponding sketch of surface landscape (upper images). Notice the positions of streams (lines make a “V”), the closely spaced contours indicating steep slopes, and the widely spaced contours indicating gentle slopes. (http://www.nwcg.gov/pms/pubs/475/PMS475_chap2a.pdf).

Understanding Contour Maps (these are among the best illustrations for teaching about topographic maps)

Left – Perspective view illustration of contour lines on a 3-d landscape and the surface represented by the contour lines. Right – Creating a topographic profile from contour lines indicating a hill and displaying slopes (http://en.wikipedia.org/wiki/Contour_line).

Illustration of contour lines and a corresponding topographic profile

Color contour maps can be easier to visualize. Left – Color contour map from USA Today of forecast temperatures for the U.S. Warm colors indicate warm temperatures, cool colors indicate cool temperatures. Right – Close-up view of a portion of the map at left, with contour lines added. Each contour line connects locations of equal forecast temperature and separates areas of higher and lower temperatures. For example, the 60o F contour separates areas of cooler forecast temperatures (less than 60o F) from areas of warmer forecast temperatures (greater than 60o F).

Color contour map

of forecast daily high

temperatures and

contour lines.

Illustration of contour lines on USA Today Daily Weather Map

West Lafayette topo map and Google Earth image

Raised relief maps

Plastic raised relief map of Death Valley, CA area. Topographic relief and contour lines are shown.

Example: Mt. St. Helens Volcano

Almost everyone, including young students, knows what a volcano looks like.

Three-D visualization from topo map, photos, and models.

Good connection to geology – before and after May 18, 1980 eruption.

Perspective view (colors and image represent the shape of the mountain) of Mt St. Helens topography (after the May 18, 1980 eruption) plotted above the corresponding topographic contour map (http://www.groundwatersoftware.com/grapher.htm).

Mt. St. Helens topo map and perspective view

Section of Mt. St. Helens topo map captured from Word document (or original pdf) by reducing or enlarging the image and using screen capture (Fn + Prnt Scrn)

Mt. St. Helens topo map (1998)

1998 Map 2011 Map (computer contoured)

1958 Map (15 minute) 1998 Map (7.5 minute)

1958 Map (15 minute) 1998 Map (7.5 minute)

May 18, 1980 Eruption Crater Rim

Almost 1000 meters of mountain removed here

Dog’s Head

Mt. St. Helens photo from the North, before the May 18, 1980 eruption http://volcanoes.usgs.gov/volcanoes/st_helens/st_helens_multimedia_gallery.html

Dog’s Head Mt. Adams

Mt. St. Helens, May 19, 1982, view from the North, Lyn Topinka (USGS) photo http://volcanoes.usgs.gov/volcanoes/st_helens/st_helens_multimedia_gallery.html

Bathymetry box activity

Bathymetry box made from plastic storage box (shoe boxes could also be used). Because the ocean bathymetry (made with clay or plaster of Paris) inside the box cannot be seen, the exercise is a true inquiry activity that includes measuring, data recording, preparing a 3-D model of the bathymetry that aids in visualization, and contouring the depth measurements. An assessment of student performance occurs when the boxes are opened and the students find the bathymetry feature/box that matches their measurements and 3-D model, and can determine the accuracy of their result.

Grid for depth measurements (using a measuring stick with cm marks) and recording depths. The grid can also be used to produce a contour map of the depths (see below).

3.5 4.0 4.5

It is very important (as with any data collection and measurement method) to have accurate record keeping (in this case by correct row and column location), and procedure (in this case keeping the measuring stick vertical when probing the model for the depth).

Contour map of grid of depth measurements. The contour lines show that the depths increase relatively smoothly from the upper left to the lower right in the model bathymetry. This might correspond to a continental slope ocean feature.

Photo of the inside of one of the bathymetry boxes showing the clay model representing ocean seamounts.

Above - make a depth profile along each row location (from A to H) and attach to the grid at each column location (1-12) to create a 3-D model of the bathymetry to aid in visualization. Left - Photo of a completed model from a team of fifth grade students.

Fold here

Profile

Ocean Bathymetry Features – Continental Shelf and Slope

Note: the slope is vertically exaggerated in this diagram. http://www.terrasonics.com/geo100_pres3b_files/frame.htm

http://www.mbari.org/canyon/Mapping_Sections.htm

Ocean Bathymetry Features – Monterey Canyon

Ocean Bathymetry Features – Loihi Seamount (just southeast of south shore of the Big Island)

https://en.wikipedia.org/wiki/L%C5%8D%CA%BBihi_Seamount

Ocean Bathymetry Features - Mid-ocean Ridge, perspective view, colors indicate depth with red indicating shallow depth and blue deep depth to ocean bottom (East Pacific Rise, off coast of WA and OR).

http://oceanexplorer.noaa.gov/explorations/05galapagos/background/mid_ocean_ridge/mid_ocean_ridge.html

Topo box Capulin Mountain, New Mexico

Fill with water to various depths to trace contour lines.

Folsom, NM (Capulin Mountain) 1972 7.5 minute topo map

Google Earth Capulin Mountain Image

Google Earth Capulin Mountain 3-D Image perspective view.

Google Earth Capulin Mountain 3-D Image perspective view with 2x Vertical Exaggeration.

Three-D foam models of topography (each layer of foam represents 200 meters of elevation) of Mt. St. Helens before (left) and after (right) the May 18, 1980 eruption.

Mt. St. Helens 3-D foam models

“Salad tray” 3-D model of Mt. St. Helens topography (before the May 18, 1980 eruption) made by drawing contour lines on clear plastic salad trays (one line for each elevation for each salad tray, then stacking them together to form a 3-D model. Viewing from different angles provides a realistic view of the shape of the mountain as well as illustrating the contour line image representation.

Mt. St. Helens 3-D “Salad Tray” models

Other visualization aspects:

Use multiple approaches to reinforce.

Connect to interesting Earth science topics – volcanoes, ocean bathymetry, local topographic and Earth science features, National Parks, etc.

Understanding vertical exaggeration.

0 0.5 1 1.5 2 2.5 3 3.5 4

x 104

0

2000

4000

Distance (m)

Ele

va

tio

n (

m)

Elevation Profiles, Mauna Loa and Mt. St. Helens (No Vertical Exaggeration)

0 0.5 1 1.5 2 2.5 3 3.5 4

x 104

0

2000

4000

Distance (m)

Ele

va

tio

n (m

)

Elevation Profiles, Mauna Loa and Mt. St. Helens (2X Vertical Exaggeration)

Illustration of Vertical Exaggeration. Note that the units of the horizontal axis are meters time 10,000. Also, note the differences in slope of the basaltic Mauna Loa and rhyolitic Mt. St. Helens profiles.

Example of vertical exaggeration for photograph of a car. Note the distortion in the lower photo (3X exaggeration).

Example of vertical exaggeration for Google Earth images of Mt. St. Helens (Mt. Hood, Oregon in the background).

High resolution, printable, 11x17 inch MS Word file of Mt. St. Helens topographic map (1998, 7.5 minute, original scale 1:24,000). If you have Adobe Acrobat Pro, you can open the St. Helens downloaded pdf file (move it out of the zip folder first), than open with Acrobat Pro and save as a jpeg file. It can then be pasted into an 11x17 Word document and printed on color for a convenient copy of the topo map. Of course, if you have access to a poster printer, you could print at full size. Or, you can crop the map to print just the area of interest. It’s useful to include the scale at the bottom of the map by saving an image of the scale (at the same enlargement/zoom as the map) and pasting into the map document.

Handout maps – 11 x 17 copies

San Francisco North 1995 7.5 minute topo map

Half Dome, (Yosemite Valley) 1997 7.5 minute topo map

Handout maps – 11 x 17 copies

The USGS Store and Map Locator & Downloader: http://store.usgs.gov/b2c_usgs/b2c/start/%28xcm=r3standardpitrex_prd%29/.do

Click here to download maps

Enter map name here (such as Mt. St. Helens, or a city near your area of interest), then hit enter.

You will see many map names. Zoom in with the Plus (+) link (upper left). Mt. St. Helens map will be shown by the marker.

Click on the Marker on the map. A list of available maps to download will appear. Select the map to download by clicking on the map size.

We’ve selected the 1998 7.5 minute topo map, size 17.57 MB. It will be downloaded (will take some time) as a zip file. You can rename it when it is saved. In general, we like the pre-2010 maps. If you double click on the zip folder, it will open as a .pdf file that can be enlarged on your screen and moved to focus on a specific area. You might need 7-Zip to open the zip folder.

Topographic Maps CD: http://www.tasagraphicarts.com/progtopo.html

USGA Topographic Map Symbols: http://pubs.usgs.gov/gip/TopographicMapSymbols/topomapsymbols.pdf

Topographic Maps information: https://en.wikipedia.org/wiki/Topographic_map

Topographic Map Resources

100 Topographic Maps: http://www.amazon.com/American-Educational-Topographic-Height-Length/dp/B00657W6JK

27 Ideas for Teaching with Topographic Maps: http://education.usgs.gov/lessons/teachingtopomaps.html

The USGS Store and Map Locator & Downloader: http://store.usgs.gov/b2c_usgs/b2c/start/%28xcm=r3standardpitrex_prd%29/.do

Hubbard Scientific raised relief maps: http://www.amazon.com/s?ie=UTF8&page=1&rh=i%3Aaps%2Ck%3Ahubbard%20scientific%20maps. Also: http://www.metskers.com/23181/Raised-Relief-Maps.html

Topographic Map Resources

How to Teach with Topographic Maps: http://www.amazon.com/dp/0873551249/?tag=mh0b-20&hvadid=4960009760&hvqmt=e&hvbmt=be&hvdev=c&ref=pd_sl_9ncs0v4wo0_e

How can I use topographic maps? (many activities): http://serc.carleton.edu/mathyouneed/slope/index.html

Lesson Plan for Bathymetry exploration (similar to this presentation): http://oceanexplorer.noaa.gov/edu/curriculum/section2.pdf

PDF of Bathymetry Box instructions and illustrations (this presentation) : http://web.ics.purdue.edu/~braile/new/BathymetryBoxInstructions.pdf

Topographic Map Resources

FOSS Landforms Kit (includes Mt. Shasta contour activity): http://www.deltaeducation.com/stem-solutions/core/foss/second-edition/landforms

FOSS Contour Mapping Activity Kit (Mt. Shasta): https://www.deltaeducation.com/stem-solutions/science-resources/earth-science/geography-landforms/contour-mapping-activity-kit/contour-mapping-activity-kit

Contour Model Kit (“topo model”; Capulin Mountain): http://www.flinnsci.com/store/Scripts/prodView.asp?idproduct=15345

Topographic Map Resources