Lesson 5 will take us one week to complete. The topic here (also worthy of a course in itself) is climate change and its impact on sea level and the coastal zone. Our plan is to first study the methods, data, and observations related to past, present and future sea level change, then evaluate the impact of sea level change on the coastal zone. We will examine the interplay of data and models as well --inasmuch as future predictions are model based. Along the way, you will learn a little something about coastal evolution. Critical reading and evaluation of data are again key components of the Lesson. As you might surmise, future sea level rise is a controversial topic. We'll have some fun with the blogosphere and media distortion of scientific results.
By the end of Lesson 5, you should be able to:
As you work your way through these online materials for Lesson 5, you will encounter additional reading assignments and hands-on exercises and activities. The chart below provides an overview of the requirements for Lesson 5. For assignment details, refer to the lesson page noted.
LESSON 5 Reading and Activities
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REQUIREMENT |
Due
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SUBMITTED FOR GRADING? |
Reading: Sea Level Rise, After the Ice Melted and Today | March 14 (target) | |
Reading: Chapter 5.5 (IPCC Report) Observations: Oceanic Climate Change and Sea Level (this is a biggie!) Activity 1: Questions regarding sea level mechanisms and timing |
March 16 (target) |
Essential Background Reading Yes, Angel Dropbox Question 8 in discussion forum |
Reading: "Birth of the modern Chesapeake Bay estuary" Activity 2: Questions regarding methodology and implications |
March 18 (target) |
Yes, Angel Dropbox |
Activity 3: Evaluating rates of sea level rise |
March 18 (target) |
Yes, discussion forum |
Activity 4 (Extra Credit): Plotting future coastlines | March 20 | Yes - Submit this assignment online with comments on implications |
Activity 5: Teaching and Learning (commentary) | March 20 | Yes--discussion forum |
Post them to our Questions discussion forum on ANGEL or get in touch by email.
Yes, here is an essential question. Perhaps today's economy is not encouraging, so none of you are rushing out to purchase that beachfront house for the summer. But, let's assume that you have a cool million (or two) dollars languishing in your accounts--perhaps Bernard Madoff has just provided you a return on your investment! Would you go to your favorite coastal area, engage a real estate agent, and put in a bid for one of the many properties now available? Remember, buying when the market is down can make for good investments. Or would it in this case? The question is "what would you look for in a coastal property?"
Rather than answering that direclty, let's embark on a consideration of the controversial topics of global climate change and resulting sea level change. Perhaps, after a reasonably intensive study of controls on sea level and predictions for the future, you will get cold feet on the coastal property purchase. Let's hope that it's not because you are standing inches deep in cold seawater in your living room! This fanciful artist's conception of Venice after a meter of sea level rise is not so far from reality. Engineers are, as we speak, planning an elaborate system of gates to prevent flooding of Venice while still allowing seawater to cycle through the adjacent wetland estuaries.
Click on the links below.
Sea Level Rise, After the Ice Melted and Today [1] By Vivien Gornitz — January 2007
(Note that Figure 1, Relative Sealevel rise, has a typo: the y-axis should be in m, not cm)
Why is an understanding of future sea level so critical? It's the economy, it lives in the balance...! Think about the implications of meters of sea level rise in a short period of time. According to modeling studies, a category three hurricane (not the most severe by any means), given a certain critical storm track to the west of Manhattan, could create a storm-surge (more on this in a later lesson) of up to 6 meters at JFK Airport, 7 meters at the Lincoln Tunnel entrance, 8 meters at the Battery, and 5 meters at La Guardia Airport. The numbers could be larger if the storm passage coincides with high tide and if one considers the height of waves riding on the surge. What if sea level were, on average, a meter or two higher? Catastrophic flooding, loss of property, life and enormous cleanup costs. Certainly, hurricanes have affected New York City in the past. One made landfall at Jamaica Bay on Sept. 3, 1821 with a 13-foot storm surge, causing widespread flooding in lower Manhattan. The "Great Hurricane of 1938," [2] a category three storm, tracked across central Long Island and southern New England on Sept. 21, 1938. The storm pushed a 25-35 foot high wall of water ahead of it, sweeping away protective barrier dunes and buildings. Some 700 people lost their lives during this storm. Things could be worse with any rise in sea level. The image below projects flooding associated with a Category 3 hurricane, as described above, with projections for additional flooding anticipated with given rises in sea level through 2050. Looks as though these "experts" might expect as much as 47 cm rise in the next 40 years. Hmmm, that's just over 1 mm per year. What is the present rate of rise? Is it expected to slow? On to the next phase of this lesson.
So, here is the (late?) great state of Florida flooded by a 5-meter rise in sea level (dark blue) and a 10-meter rise (light blue). Yes, far in the future, but not beyond imagination should, for example, the Greenland ice sheet completely melt back. Miami is gone, Tampa is gone...At what cost? When you take a look at a map of elevations around Miami, for example, you find that much development has occured at heights above sea level of only 1 meter or so (see next chapter). Amazing! Could we ever do anything to save this region--short of building an elaborate set of dikes (like those protecting New Orleans today!) or somehow reversing the effects of global warming? What's going to happen to the folks in Holland?
Sea level changes on a global, as well as local, basis because of a number of factors. We are presently most concerned with rising sea level that results primarily from warming of seawater (why?), melting of continental glaciers and ice sheets (but not sea ice. Why?). How do we know that sea level has changed in the past, and how do we monitor sea level change at present?
Time to delve into something you've certainly seen in the news -- the well-known IPCC (Intergovernmental Panel on Climate Change) Report . This section of Working Group 1 effort discusses sea level change related to climate change. This is a "consensus" report from numerous scientists--experts in their fields. IPCC Report, 2007
You can find the full set of reports here [3]
You will read Chapter 5.5 [4]in its entirely: Changes in Sea Level. You can read it in html, or pdf. This is the link for the pdf files [5]
In any case, feel free to scan over other parts of Chapter 5 as
well. Section 5.5 will provide an essential background in
preparation for the first activity, so read it carefully and make sure
you understand the data, techniques and concepts. Feel free to
post comments/questions below to the class with questions if there is
something you do not understand. We will be monitoring the
"discussions" in the event there is something really problematic that
comes up.
When you are finished reading, you will go on to the next part in this Lesson to begin Activity 1.
Figure 1: Here is an image for downtown Miami, FL, showing the
effects of a 1.25 meter rise in sea level above mean high water.
You can make your own images like this for your favorite area (later
activity). This one comes from www.architecture2030.org/.
Fig. 2: This is a plot of changes in mean sea level (in millimeters) for 1993 through 2006 using satellite altimetry data. The data suggest that sea level has risen at a rate of ca. 3 mm/y over this period. Note the smoothing and removal of "seasonal signals." Also, keep in mind that this is "mean" sea level (globally averaged). There are differences in response around the world ocean (see Fig. 3 below).
Figure 3: This map for 1993-2008 shows the average rates of change in sea level for small blocks of the ocean on the basis of satellite altimetry data. This illustrates the wide variation in rate and direction of sea level change globally. Much of the ocean is in the "green" zone, hovering near the globally average rate of 3 mm/y. But what about those anomalies?
After reading the first two assigned articles and examining the figures above, answer the following questions. You may simply provide a list of elements, when appropriate. Elaborate if you like. Number 8 will be a basis for discussion, so that will be posted in the "Comments" box below.
For numbers 1 through 7, please put your answers in a file and drop that in the dropbox on Angel.
For number 8, use the comment box below.
Save your document as either a Microsoft Word or PDF file in the following format:
L5_Activity1_AccessAccountID_LastName.doc (or .pages or .pdf)
For example, student Elvis Aaron Presley's file would be named "L5_Activity1_eap1_presley.doc".
See the grading rubric [7] for specifics on how this assignment will be graded.
Figure 1: Digital map of water depths in the Chesapeake Bay Estuary compiled from data found on the NOAA website (http://estuarinebathymetry.noaa.gov/finddata.html [8]). You can build your own for your favorite estuary using the website. Files are quite large, but very elucidating. Note the deepest value of nearly 53 meters in the estuary. Why do the deeper channels tend to hug the east side of the estuary? Is this Coriolis?
In this chapter of Lesson 5, we will examine one role of sea level rise in coastal evolution--that of the formation of estuaries. Of course, estuaries are an important feature of the coastal region because they provide water routes to inland regions for shipping, defense, etc., and because they are typically nurseries for the larvae and immature stages of many marine organisms as well as being important fisheries. In this course we will concentrate on the Chesapeake Bay estuary because of its proximity to us and importance to the economy of the mid-Atlantic region. Those of us in University Park, PA have a direct connection to the Chesapeake because we live in the Susquehanna River watershed which ultimately dumps into the Chesapeake Bay. We'll begin here with a study of the formation of this estuary, and in subsequent lessons we will explore the ecosystem itself and the problems it faces now.
Click on the links below to access a scientific article on the origin of Chesapeake Bay. Read this paper and think about the evidence that these scientists use to reconstruct the early history of this estuary and the timing and impact of sea level changes. Note the importance of the 8.2 thousand year "event."
Let's outline some aspects of the work of a sedimentary geologist who is trying to reconstruct the timing and early history of an estuary. Answer the questions below to provide an overview of their approach and methodology. Again, for some questions a short answer or list will suffice, but support your conclusion with further discussion if appropriate. Submit your ms word or pdf document as outlined below and drop into the Angel dropbox for Lesson 5.
Save your document as either a Microsoft Word or PDF file in the following format:
L5_Activity2_AccessAccountID_LastName.doc (or .pages or .pdf)
For example, student Elvis Aaron Presley's file would be named "L5_Activity2_eap1_presley.doc".
See the grading rubric [7] for specifics on how this assignment will be graded.
Figure 1: Our next investigation revolves around this figure, based on Holgate (2007), an article you will read below. This image might suggest decadal variations in the rate of sea level rise (or fall). It is based on tide-gauge data, one of the critical components necessary for documenting historical sea level changes.
Let's evaluate some of the data sets required to establish the history of sea level changes. This history can provide a perspective on more recent rates of change. Inasmuch as it is our goal to encourage you and your students to critically evaluate scientific hypotheses and data, this is another in a series of issues that deserves deeper study. In particular, this is an opportunity to see how the media respond to various issues and how individuals might distort conclusions of scientific papers, or selectively extract certain data or plots, to further their own objectives. It will not surprise you to find that there are skeptics regarding the predictions of the IPCC Report and others. We will examine some of them and attempt to analyze their methods and mistatements or misleading conclusions. You can have some fun with this. You should do it all in discussion format, responding to one anothers posts in response to the questions in Activity 3 below.
This is the scientific paper published in 2007 by S.J. Holgate, a reputable scientist studying sea level changes at the Proudman Oceanographic Laboratory, Liverpool, UK (wonder if he listens to "Yellow Submarine" when he writes his papers?). The paper is a critical evaluation of tide gauge data used in reconstructing sea level history. You will need to read this paper, which is not too technical but detailed, to understand how tide gauges are used and their strengths and weaknesses. The paper also emphasizes spatial statistics, which are an important consideration in global reconstructions. After reading the paper, take on Activity 3.
A) You have read the Holgate paper. In your own words, summarize the principal points he made and their significance. Do this in less than 100 words.
B) Now, let's see what the response to Holgate's paper was--not so much from the scientific community, but from the "Blogosphere", which, of course, does include scientists. Some of them are skeptics regarding climate change in general. Do some web-based research and see what you can find regarding the use and abuse of Holgate's data and conclusions. Are all the responses you found above board?
Here are two examples of posting sites or blogs that responded to this article. Note the interesting names that give them credibility. Is there a purpose behind the "science?"
World Climate Report [11]
CO2 Science [12]
Provide two or three examples of blogs or other postings that distort the findings of the Holgate article in some way. How did they do this and what was their purpose? Make sure you point out exactly how they strayed from the findings reported in Holgate. Or, did they take issue with Holgate and show that he was wrong in some way?
You should deal with these issues through the comment field below. The quality of your analysis and comments and response to others is the key component here.
See the grading rubric [7] for specifics on how this assignment will be graded.
Figure 1: illustrates a line for 3-meter flooding around Waikiki on the island of Oahu
Think again about the economic and human consequences of sea level rise. Developed areas would be flooded at great cost, or, we would have to spend inordinate amounts of "public" money to protect them. In areas such as Bangaladesh, sea level rise would wipe out agricultural production and cause huge loss of life (which already occurs during cyclones in the Indian Ocean).
Sea level rise will inexorably cause the coastal zone to "step back" just as has occurred over the past 18 thousand years as wave attack erodes cliffs and moves sand from beaches farther onshore and offshore. Our favorite barrier island beaches will evolve, but the houses on them will be destroyed or moved back at great cost.
Check out the information here [13]regarding Waikiki Beach shown in Figure 1. You can go to Chip Fletcher's (University of Hawaii) website to see how he constructed this image. Note that he endorses a policy of "managed retreat." Huh? What's that?
A) Take your favorite beach and find a topographic map and aerial/satellite photo of it (TerraServer, Google, Topomaps.com, etc.). Take only a small chunk of this area (you don't want to spend too much time on this) and try to draw a line on your map, like Fletcher did for the Waikiki area. What would be lost in/around your beach (town) if sea level rose 3 meters?
B) What is "managed retreat" ? How could this be accomplished?
Submit your diagram and discussion through the comment field. The quality of your analysis and comments and response to others is the key component here.
See the grading rubric [7] for specifics on how this assignment will be graded.
Let's take some time to reflect on what we've covered in this lesson. Remember, you should also be working towards your term project this week with a due date for concept outline this week.
For this activity, we want you to reflect on what we've covered in this lesson and to consider how you might adapt these materials to your own classroom. Would these activities work for high school students? Could you get them to read critically? Since this is a discussion activity, you will need to enter the discussion forum more than once in order to read and respond to others' postings.
You will be graded on the quality of your participation.
Here are several more web sites. We highly recommend the Real Climate site as a resource to understand the nature of arguments for and against human-induced global warming and its consequences. This is a moderated site, but allows dissenting viewpoints. Very balanced.
Have another reading or Web site on these topics that you have found useful? Share it in the Comment area below!
Please do not forget to make progress on your Capstone project.
See details on 'Course Schedule'
You have finished Lesson 5. Double-check the list of requirements on the Lesson 5 Overview page to make sure you have completed all of the activities listed there before beginning the next lesson.
If you have anything you'd like to comment on, or add to, the lesson materials, feel free to post your thoughts below. For example, what did you have the most trouble with in this lesson? Was there anything useful here that you'd like to try in your own classroom? Is climate change a topic you and your students are interested in? Do your students have much interest in or opinions about the politics/science of global climate change?
Links:
[1] http://www.giss.nasa.gov/research/briefs/gornitz_09/
[2] http://www2.sunysuffolk.edu/mandias/38hurricane/
[3] http://www.ipcc.ch/publications_and_data/publications_and_data_reports.shtml#1
[4] http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch5.html
[5]
http://www.ipcc.ch/publications_and_data/publications_ipcc_fourth_assessment_report_wg1_report_the_physical_science_basis.htm
[6] http://www.architecture2030.org/current_situation/research/sea_level/appendix.html
[7] https://www.e-education.psu.edu/earth540/grading_rubric_problemsets
[8] http://estuarinebathymetry.noaa.gov/finddata.html
[9] https://courseware.e-education.psu.edu/courses/earth540/priv/Bratton2003.pdf
[10] https://courseware.e-education.psu.edu/courses/earth540/priv/HolgateGRL2007.pdf
[11] http://www.worldclimatereport.com/index.php/2007/02/09/shocking-facts-about-sea-level-rise/
[12] http://www.co2science.org/articles/V10/N4/C1.php
[13] http://archives.starbulletin.com/2007/09/23/news/story01.html
[14] http://www.realclimate.org/index
[15] http://epa.gov/climatechange/wycd/school.html
[16] http://www.pbs.org/wgbh/nova/vinson/ice.html