I. Oil Spills: Where will the Spilt Oil Go?
Objective: Students discover how real-time data can be useful for managing oil spills
Background
GNOME predicts movement of spilled oil using calculated movements of water and the air immediately above the water's surface. GNOME predictions of oil spill movement can be based on average data for a particular time and location. Real-time data such as the NOAA PORTS real-time database can be used to further refine predictions. The NOAA PORTS database is located at:
http://www.co-ops.nos.noaa.gov/d_ports.html
Materials
Copies of the Student Worksheet
General NOAA Oil Modeling Environment (GNOME) Simulation Software ready for use on each computer used in the activity. This free software and associated information are available at:
http://response.restoration.noaa.gov/ software/gnome/gnomeinfo.html.
Exercise 1. The Delaware Bay spill
Assume that you are in charge of an emergency oil spill team that must minimize the effects of oil spills from tankers coming into the Delaware Bay. You get a call on July 20, 2004 saying that a tanker released 100,000 barrels of nonweathering crude oil at noon on Brandywine Shoal (Latitude: 38o 57.49' North, longitude: 75o 4.67' West). You know from meteorological tables that the average wind speed at this site is 25 knots from the North during July. On the map below, indicate where you will send your team and equipment to prepare for the oil landfall. If you pick the correct sight (i.e., within a few miles of the actual landfall) and have 12 hours to prepare, you can effectively place absorbents and booms to protect critical habitat and establish waterfowl rescue centers to save oiled birds.
(From NOAA: http://www.co-ops.nos.noaa.gov/dbports/db_map.html)
Let's check how you did by using a program (GNOME) employed by coastal managers to predict where spilt oil goes. GNOME integrates water and air movement to predict oil movement. It will use mean water flow data for the spill site in these exercises, not data actually measured at the site during the event. The coastal manager's job is much more effective when they have real-time data to plug into the model. Later, we'll to illustrate this point by going to PORTS, a source of real time data.
GNOME Simulation Software (shareware from http://response.restoration.noaa.gov/software/gnome/gnome.html)
Envoking the GNOME:
1. Double click the GNOME icon on your desktop.
2. Click OK in the first gray screen.
3. Read the Welcome to GNOME screen and click Agree if you agree.
4. The next screen will say, selecting a location file. Click select file.
5. Navigate to the file called Delaware Bay.loc.
Simulating an Oil Spill in Delaware Bay:
1. After you select the DelawareBay.loc file, a window will appear with the heading "Welcome to Delaware Bay." Click next.
2. A new window will appear with the heading "s."
3. For the model start date, select July 20, 2004.
4. Change the model start time to noon (1200).
5. For the model duration, select 3 day and 0 hours. Click next.
6. A new window appears titled "Choosing wind type". Click next.
7. A new window appears titled "Constant wind". Choose 25 knots from the North and click next.
8. A new window appears titled "Almost Done". Click To the map window.
9. The window will disappear and you will view a map of Delaware Bay. On the left there is a summary list. Check the box that says "Show currents". The currents are now shown as an array of vectors over the surface of the Delaware Bay.
10. Now, let us create an oil spill.
11. Double click spills in the summary list. A window appears titled "Add new spill"
12. Choose "Point/Line Source S Plots" and click Create.
13. A new window appears entitled "Spill information". For the pollutant, select "non-weathering". Enter 100,000 barrels for the amount released. For the location of the spill, type in 38° 57.49' N, 75° 4.67' W. Select Change and Okay. At the top of the window, go to model and click run from the menu.
You can save the results as a Movie. Open the File menu in the top right corner. Select Save. As type, choose Quicktime Movie. Select OK and save your movie in a suitable place. If you would like, you can generate some other examples for your class and save them.
How accurate were your initial team deployments?
Let's see if some real-time wind data can improve predictions.
GNOME Program and PORTS Data Combined
These predictions for landfall were based on mean data for that date, location, and time of day. The NOAA PORTS database which is located at
http://www.co-ops.nos.noaa.gov/d_ports.html can be used to refine predictions even more. We'll use only wind speed real-time data to illustrate this point.
1. Go to the PORTS site.
2. Select "Delaware River and Bay"
3. Select "Click Here to Observe a List of Delaware River and Bay PORTS-observation"
4. Go to "Brandywine Shoal Light".
5. Select "All Meteorological" for Brandywine Shoal Light.
6. Scroll down to Brandywine Shoal Light and find the actual wind speed and direction. (Wind direction is given as degrees on a compass where North is 0o, East is 90o, South is 180o and West is 270o. So a wind direction of 90o would indicate a wind blowing from exactly East.)
7. With your real-time wind direction and speed information, redo the GNOME simulation.
8. Did you get a different oil deposition pattern?
Answer:
Emergency managers use real-time data such as those shown on the NOAA PORTS sites to make important predictions. Without such data, predictions can be inaccurate and misleading.
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Exercise 2. The Chesapeake Bay spill
The Scenario
You are an environmental manager working for the National Oceanographic and Atmospheric Administration's (NOAA's) oil spill response team. On January 7, 2004, you received a call claiming that an oil spill has occurred in the Chesapeake Bay. The freight company who owns the ship claims the tanker was en route to Baltimore before hitting an underwater hazard approximately 3 hours ago. Your response team has floating booms to contain the oil and cleaning equipment. However, they will not be able to contain the spill in another 21 hours. Time is needed to prepare and they anticipate problems with a heavy fog in the region. Administrators at NOAA are interested in finding out what resources may be impacted and what shorelines could get coated with oil before the team can contain the spill. Luckily, you have an oil spill model, called GNOME, to predict where the oil will go. You also have an internet resource, called OSCAR (CCIP, 2001), with various habitat types in the region. Let's see what you can find!!!
Before we begin. . .
This exercise assumes you have already downloaded GNOME and installed it on your computer. If you have not, see the appendix for details.
Getting started
Now let us use GNOME and OSCAR along with some data on winds and currents to predict where the oil spill will go:
1. Open GNOME. Go to Start -> Programs -> GNOME -> GNOME.
2. Once in GNOME, click OK on the window that pops up in the first screen.
3. On the second screen, if you agree, click "Agree".
4. On the next screen, it asks you to select a location file. Click "Select File." When the next screen opens asking you to open a file, click "Cancel."
5. You will now be in the GNOME modeling environment. However, you will have an empty map. Place GNOME in Diagnostic Mode (File Menu -> Preferences -> Mode Tab). Once you are under the Mode tab, select the circles next to Diagnostic on either side of the menu.
Let's get the Chesapeake Bay on our map!!!
1. Unzip the Ches Test.sav file that is included with this document. If you do not have the .sav file, email newman@vims.edu to receive a copy of it. Put the Ches Test.sav file in a place that you can find it, preferably the GNOME folder in your Program Files.
2. Let us get the location file up for the Chesapeake Bay.
3. Open the Ches Test.sav file in GNOME (File -> Open). This file contains the map. Importing it could take a few minutes due to the detail of the map.
4. Now we have a map open with the Chesapeake Bay.
You can zoom into sections of the map by clicking on the magnifying glass with a plus sign in it above the map window.
You can zoom out by clicking on the magnifying glass with a minus sign in it above the window.
To move up and down in the map view, click the hand above the map window and, using your mouse, grab a piece of the map and pull it up or down.
It's spill time
Let us place the oil spill on the map. Make sure your view is large enough to see the entire Bay. Approximately 25,000 barrels of oil were released from the tanker as the tanker was en route to Baltimore.
1. On the menu on the left in the GNOME window, click "Spills."
2. In the Window that pops up, select "Point/Line Source Plots" and press "Create."
3. In the field where it says "Amount Released", indicate that 25,000 barrels spilled. Release start should be 1/6/2004 and the start time is 12:00.
4. Place the spill at 39 degrees, 15.69 min latitude and at 76 degrees, 19.16 minutes longitude. Click OK.
5. In the "Change Model Start Time?" window that pops up, select "Change."
So, what may be affected by the oil spill?
Before watching the spill, let us go to an internet resource that can point out some of the important resources in the Chesapeake Bay that may be impacted. Go here: http://ccrm.vims.edu/output/virginia/disclaimer_oscar.html.
1. Click on "Go to the Oscar web site" text and read the disclaimer.
2. When you get to the OSCAR window zoom in a bit on to Northern Chesapeake Bay.
3. On the side of the map is a narrow window that says "Data layers." This window allows us to add layers to the map to view different resources around the Bay. Put checks under the visible column next to:
a. "Surface Drinking Water Intake Sites",
b. "Shoreline sensitivity",
c. "Populated Places",
d. "Underwater Grass Beds",
e. "Maryland Natural Oyster Bars",
f. "Maryland Natural Heritage Areas" and
g. make sure that "Chesapeake Bay Shoreline" and "Inland Area Contingency Plan Boundary (EPA)" are already checked.
4. Click "Refresh Map" when you are through. You should see new layers on the map.
5. To view what the layers are:
a. Place a check mark next to a layer name in the side window under the column that says "Active".
b. Then click the white "i" that is in a black circle and red square under the tool bar. You can select features on the map doing this and it will explain to you what they are.
It's spill time!
1. In the GNOME window, play the simulation to see where the spill goes. Press the play button above the map to watch the oil spill go. Zoom into the area where the oil spill occurs after playing and watch again.
2. Save the movie file you have made by going to File ->Save and select Quicktime movie from the menu. If you do not have the Quicktime player installed on your computer, go here: http://www.apple.com/quicktime/download/
Some food for thought
Answer the following questions from the oil spill you just observed:
1. What resources were impacted by the spill?
2. Do you think that those resources that the spill did not stop at, but went through, were impacted?
3. Were any shorelines affected?
4. In 24 hours, do you think your crew will be able to contain the spill as effectively as when it first occurred?
5. Do you think a spill is harder or easier to clean when it is on the shore or when it is on the water's surface?
6. What other information do you think you need to make a better prediction about where the model will go?
Let's get some currents for the day
Now pretend that a colleague has given you a file for GNOME with predicted currents for the day. For currents, we are going to download and use the 200401071200_C3PO_fieldsnow.nc current file for the Chesapeake Bay model.
1. To do this, go to this web site:
http://208.255.155.35/c3po/archive/netcdf/
2. Once at the web site, choose the 200401/ folder. This directory has some current files for the Chesapeake Bay with a .nc extension that can be imported to GNOME.
3. Download the file 200401071200_C3PO_fieldsnow.nc.
Adding currents
Now, let's try the same simulation using forecasted currents.
1. Double click the "Movers" under the Maps heading in the menu on the left of the screen, select "Currents" from the pulldown list and click "Load".
2. Go to the 200401071200_C3PO_fieldsnow.nc file and double click it.
3. When it asks if you have an extended topology to load, click "No." The download may be slow due to its large size.
4. When the "External Current Mover Settings" window appears, make sure "Active" is selected and "Show Velocities" is not selected. Click "OK."
Watching the spill with currents
1. Zoom into the area where the oil spill occurred and press play to watch the movie file.
2. Now examine the resources map and determine if any different resources could be impacted with the currents added in.
3. Double click the 200401071200_C3PO_fieldsnow.nc under Maps-> Movers in the menu on the left. Select Show Velocities. The currents are now viewed as vectors. To learn more about vectors, visit here:
http://www.coolclassroom.org/cool_projects/tutorials/codartutorial.html.
4. Now zoom in to the spill and watch it go! Save it as a movie file and go back and see if any of the questions you answered in the Food for Thought section are different with currents added.
So will wind have an affect?
The final variable that will be added is wind.
1. Go to http://www.ndbc.noaa.gov/Maps/chesapeake_bay_hist.shtml.
a. On the map of meteorological sites around the Chesapeake Bay, click on the red triangle for the site near the oil spill.
b. If you put your cursor over the correct red triangle (without clicking), it should say TPLM2.
c. The next page has some real time wind measurements at that site.
d. Go to Historical Data & Climatic Summaries at the bottom of the page and click on it.
e. Select Continuous Winds Data for the year 2004. Download tplm2c2004.txt.
2. The text file you just downloaded can be opened in Notepad or Microsoft Word. Open either of those first and then go to file->Open. Find where you downloaded the text file and open it. You may have to select All Files under the Files of Type menu, before you can open it. Now look at the file. There are several headings for columns with wind data. DIR is direction in degrees from North. Thus, 90 would be east, 180 would be south, 270 would be west, 360 or 0 would be north. The speed of the wind is measured in knots.
3. In the open text file, scroll down to January 6, 2004 starting at midnight and look at the data until midnight, January 7, 2004. The wind is variable and this variability can be included in GNOME.
4. Pretend you are given a forecast of a 9 knots wind blowing from NNW. Go to the GNOME model again. Double click the Universal Movers heading in the menu on the right. A new menu will pop up. Under "Type", pick "winds-variable" and then select "Create". Place 9 knots blowing from NNW in the window, click "Replace selected", and click "OK." Run the spill again. Save this movie file also. Compare the three movies and discuss how the different types of data affected your predictions.
Note: To try this example in the lower Chesapeake Bay near the York River, substitute these coordinates:
37o 13.15 North
76o 22.04 West
Appendix I: Downloading and installing GNOME
1. Go to http://response.restoration.noaa.gov/software/gnome/gnome.html. Click on the link that says, "Get the latest version of GNOME."
2. Download the version of GNOME that best matches your system. Note: Remember which folder you place the GNOME executable file that you download in.
3. Click on the GNOME application that you have downloaded. Follow the instructions to install.
Citations
Comprehensive Coastal Inventory Program, 2001. Oil Spill Cleanup and Response. Virginia Institute of Marine Science, College of William and Mary, Gloucester Point, VA 23062.
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