Climate Change, Tides, and Changing Seas 

By: Christine Burns and Caitlin Lauback, Technicians at UNC-Institute for Marine Sciences

 

Grade Level: High School

Subject: Earth and Environmental Science

 

Overview

This three part lesson plan will touch briefly on the mechanisms of how climate change can affect sea  level and the mechanisms driving tides in coastal Carolina. This lesson will then bring the two together to discuss how high water events caused by rising seas and extreme tides can significantly affect coastal communities. This lesson is inspired by a citizen science project called the King Tides Project, which was started to raise awareness about the potential impacts of sea-level rise. Students can use what they learn in this lesson to then contribute to the King Tides Project as an extension activity or on their own.

 Goals

  • Gain a stronger understanding of the greenhouse effect and its connection to sea-level rise.
  • Gain a stronger understanding of what influences tides and why we care about them.
  • Draw the connection between sea-level rise and tides by using the existing platform of the North Carolina King Tides Project.
    • Meet the transitioning standards of STEM to STEAM by using photography as a tool to better understand the potential impacts of sea-level rise on our coastal communities

Outline and Incorporated Standards

More information on incorporated standards provided at the end of the lesson plan.
Lesson #TopicNC Essential StandardsNext Generation Science Standards
1Climate ChangeEEn.2.6.3 and EEn.2.6.4HS-ESS2-2 and HS-ESS3-5
2TidesEEn.1.1.1 and EEn.1.1.2
3Coastal Resiliency and the King Tides ProjectEEn.2.6.2HS-ESS3-1 and HS-ESS2-4

 

Lesson 1: Climate Change

Materials Needed

  • Worksheets
  • Plastic Bins
  • Ice cubes
  • Cup

Materials Provided

Getting Started/Prompt Questions

Begin the lesson by asking the students to answer the lesson prompt questions [worksheet provided]. Use the students’ answers to start a brief lesson/discussion on glacial melt, atmospheric composition, and greenhouse gasses.

Key discussion points

  1. Our atmosphere does include some carbon dioxide (CO2)
  2. However, CO2 is one of the most influential greenhouses gasses when it comes to climate change
  3. Changes in % CO2 are often studied by climatologists to see how global temperatures may rise.

Additional discussion points

  1. Discuss hockey stick curve and the greenhouse effect
  2. Changes in the atmosphere contribute to ice melt
  3. The positive feedback loop that is initiated by these processes

Activity 1: Glaciers and Climate Change Lab

Glaciers have been melting at unprecedented rates. Students will investigate why we are seeing such extreme climatic changes.

Part 1: Students will evaluate changes in glacial size over time for a series of glaciers. Students will perform a qualitative analysis of these changes by observing physical change over time from photographs provided to them.

Part 2: After these observations have been established, the lab addresses the correlation between global warming (represented by changes in carbon dioxide concentrations), the loss of sea ice, and finally the rise in sea level. Here, students are required to analyze real data represented in 4 graphs to answer questions to get them thinking about the cause-and-effect nature of climate change. [Extension: using the data in the graphs, you could have your students calculate rates of change (change/time) for some of the data plotted.]

Activity 2: Sea ice versus land ice

A major argument of climate deniers is that ice in the ocean doesn’t change the amount of water in the ocean and this would be correct. When we talk about climate change and sea-level rise, we are concerned with thermal expansion of water and land ice melt. To demonstrate the difference between melting sea ice and the ice sheets on land, such as we see on Antarctica and Greenland. You will have two basins (A and B) partially filled with water. Anything you have in the room will work (even a plastic cup), but this will work best in a large shallow bin (Tupperware works great!).

Procedure

  • Place a cup or structure into each bin that is tall enough to be higher than the water line; this is your continent.
  • Place ice cubes in the bottom of Basin A (your sea ice) and on the “land” structure in Basin B (your ice sheet) and then fill each bin up partially to the same height of water (the amount of ice you choose to work with will be dependent on the size of your container, the larger the container, the more ice you should use).
  • Use a marker to mark how high the water is. Now let each container sit for a while, allowing the ice in both containers to melt (you can speed this process along with a hair dryer if you’re pressed for time).
  • Return to the containers after the ice has melted to make observations.

Expected Results

The water level in Basin A (i.e. Arctic Sea ice) will remain the same while the water level in Basin B (Antarctica) should increase.

Key discussion points

  1. Ask your students to observe differences in water levels in the individual bins
  2. How do the water levels in A and B compare to other
  3. What do you think we can expect to happen to sea level, given everything learned in the lab activity?

Extension: Depending on the amount of time and the background knowledge of your students, you can choose to let them know what Basin A and Basin B represent or you can have them try to figure it out. In addition, you can make your basins as detailed as you would like by adding low lying and high “continents” and showing that as water level rises coastal communities will be in jeopardy. In addition, you can spur discussion on how the freshwater from your land ice will affect the salinity of your ocean surrounding those continents.

 

Lesson 2: Tides

Materials Needed

Getting Started/Prompt Questions

Begin the lesson by asking the students to answer the tides lesson prompt questions [worksheet provided]. Use the students’ answers to start a brief lesson/discussion on the orbits of the Sun and moon. Use NOAA graphics as a visual tool: http://oceanservice.noaa.gov/facts/perigean-spring-tide.html

Key discussion points

  1. The shape of these orbits
  2. How this affects the water on earth (oceans, lakes, and rivers).

Activity: Modeling the orbits of the earth, sun, and moon

This activity can be done with the entire class, or the class can be broken up into smaller teams and “compete” for the most accurate response.

  • Have one person hold the earth
  • Have the person with the earth stand in place while someone else, acting as the moon, orbits around them. Help them make an elliptical orbit.
  • As the moon hits different points in orbit, stop the students and talk about what the tide might look like at that time.
  • Once they have a handle on that, add in the earth’s rotation around the sun.
  • Stop them at points when the sun and moon are canceling each other out (and our tidal range is smaller) and then at points when the sun and moon are reinforcing each other (to give us greater tidal range).
  • Once they feel really good ask them to achieve different scenarios (i.e. if you asked them to create the perigean spring tide, they would need to line the sun, earth, and moon up).

 

Lesson 3: Coastal Resiliency and the King Tides Project

The final section of the lesson connects what we’ve learned about tides and what we’ve learned about climate change and sea-level rise through debate and project-based learning. The Intergovernmental Panel on Climate Change (IPCC) was formed by the United Nations to review all the scientific literature on climate change and determine what the scientific consensus is on the issues regarding climate change from how fast it’s happening to what the effects of climate change will be. In 2013, the IPCC report stated that we could expect to see up to 82 cm (2.7 ft) of sea-level rise by 2100 due to the thermal expansion of water as well as due to land ice melt.

Getting Started/Prompt Questions

  1. Will a little bit of sea-level rise really matter?
  2. What are the factors that determine how significant a little bit of sea-level rise is?
  3. Do you think you will be affected by sea-level rise? Why or Why not?

These statics were extremely concerning to Green Cross Australia given that three quarters of the Australian population lives within 30 miles of the ocean and so they created the King Tides Project. The mission of the King Tides Project is to help people better understand the impacts of climate change on their local communities by looking at abnormally high tides. As you learned from the tides lesson, there are times throughout the year when the full or new moon creates even higher than normal high tides (the perigean spring tide). These extreme high tide events are frequently associated with flooding, especially when accompanied by a storm. While these events are completely natural, they can help us visualize what our coastal communities may look like with seal-level rise and they can help coastal planners and developers understand what we need to do within our communities to prepare for the effects of sea-level rise. There are now King Tides Projects throughout the world and in many US states. In the fall of 2015, UNC-IMS began the North Carolina King Tides project.

We are asking citizen scientists, like you, to go out and take pictures at certain times of the year when we are expecting high tide events. (http://nckingtides.web.unc.edu/)

These photos need to include a vertically stable benchmark that we can later measure to collect data on how high the tide came.

They can use their smart phones to take the photos and then upload them to the Flickr group, King Tides NC.

What issues for city planners do these photos bring up?

  • Insurance agencies?
  • Tourists?
  • Shop/restaurant owners?
  • Public health officials?

Activity 1: Participate in the KT Project

Have your students go out during the next king tide event and have them take photos. Choose the best ones and upload them to our flickr page either through a school or personal account. Scientists from UNC Institute for Marine Science will revisit these sites (if they choose public locations) and take GPS measurements for elevation. With that data we can make more accurate maps and models of how sea-level rise will affect coastal Carolina. Should enough schools be interested, UNC is willing to host a formal competition complete with prizes for the winning class.

Activity 2: Debate

The North Carolina state legislation bans state agencies from discussing issues of accelerating sea-level rise. Creators of the bill were worried that dire sea-level rise reports could hurt North Carolina tourism and real estate. Organize your class into stakeholders in favor of the bill and those against. Give them roles to play. Some interesting stakeholders could be residents, policy makers, fisherman, boat owners, waterfront property owners, insurance agencies, tourists, and shop owners. The list could go on forever and many of these parties could vote both ways. Have students research and present their view and then offer time for reconsideration and rebuttal. At the end declare a debate winner.

 

Next Generation Science Standards

HS-ESS2 Earth’s Systems

HS-ESS2-2. Analyze geoscience data to make the claim that one change to Earth’s surface can create feedback that cause changes to other Earth systems. [Clarification Statement: Examples should include climate feedback, such as how an increase in greenhouse gasses causes a rise in global temperatures that melts glacial ice, which reduces the amount of sunlight reflected from Earth’s surface, increasing surface temperatures and further reducing the amount of ice. Examples could also be taken from other system interactions, such as how the loss of ground vegetation causes an increase in water runoff and soil erosion; how dammed rivers increase groundwater recharge, decrease sediment transport, and increase coastal erosion; or how the loss of wetlands causes a decrease in local humidity that further reduces the wetland extent.]

HS-ESS2-4. Construct an argument based on evidence about the simultaneous co-evolution of Earth’s systems and life on Earth. [Clarification Statement: Emphasis is on the dynamic causes, effects, and feedback between the biosphere and Earth’s other systems, whereby geoscience factors control the evolution of life, which in turn continuously alters Earth’s surface. Examples of include how photosynthetic life altered the atmosphere through the production of oxygen, which in turn increased weathering rates and allowed for the evolution of animal life; how microbial life on land increased the formation of soil, which in turn allowed for the evolution of land plants; or how the evolution of coral created reefs that altered patterns of erosion and deposition along coastlines and provided habitats for the evolution of new life forms.] [Assessment Boundary: Assessment does not include a comprehensive understanding of the mechanisms of how the biosphere interacts with all of Earth’s other systems.]

HS-ESS3 Earth and Human Activity

HS-ESS3-1. Construct an explanation based on evidence for how the availability of natural resources, occurrence of natural hazards, and changes in climate have influenced human activity. [Clarification Statement: Examples of key natural resources include access to fresh water (such as rivers, lakes, and groundwater), regions of fertile soils such as river deltas, and high concentrations of minerals and fossil fuels. Examples of natural hazards can be from interior processes (such as volcanic eruptions and earthquakes), surface processes (such as tsunamis, mass wasting and soil erosion), and severe weather (such as hurricanes, floods, and droughts). Examples of the results of changes in climate that can affect populations or drive mass migrations include changes to sea level, regional patterns of temperature and precipitation, and the types of crops and livestock that can be raised.]

BHS-ESS3-5. Analyze geoscience data and the results from global climate models to make an evidence-based forecast of the current rate of global or regional climate change and associated future impacts to Earth systems. [Clarification Statement: Examples of evidence for both data and climate model outputs, are for climate changes (such as precipitation and temperature) and their associated impacts (such as on sea level; glacial ice volumes, or atmosphere and ocean composition)] [Assessment Boundary: Assessment is limited to one example of climate change and its associated impacts.]