GARBAGE. Central North Pacific Gyre Plastic debris and other trash from around the world that is brought together by ocean currents.

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1 TEACHER PAGES GARBAGE L4 Central North Pacific Gyre Plastic debris and other trash from around the world that is brought together by ocean currents. Any persistent material that is intentionally or unintentionally left abandoned in oceans. How Should Scientists Study Plastic Micro-Debris in the Central North Pacific Gyre? By Beth Simmons (California Current Ecosystem LTER Education and Outreach) and Lara Dickens (Patrick Henry High School) INTRODUCTION: Plastic litter is not uncommon on land, but there is a difference between common terrestrial and ocean based plastic debris. Plastic does not biodegrade. Plastic that makes its way to the ocean often finds itself floating for years in direct sunlight, which makes it brittle and easily broken into smaller pieces of plastic. Scientists are concerned that the plastic collecting in the gyre has the potential to negatively affect marine life, and ultimately humans. The Central North Pacific Gyre is a region within the Pacific Ocean that circulates clockwise due to wind and the ocean currents that border it. The circulating motion draws floating objects toward its center. Biodegradable materials eventually decompose and return nutrients to the ocean. Plastic does not decompose and therefore continues to collect. Although the presence of the plastic in the Central North Pacific Gyre was documented over ten years ago by Captain Charles Moore of the Algalita Marine Research Foundation, and plastic has been collected in plankton samples from within the California Current for over 35 years, there is relatively little known about the gyre or the plastic accumulating in it (Gilfillan et al., 2009). [1]

2 Essential Questions (E.Q.): How do scientists conduct investigations and ask meaningful questions about the ocean? How do scientists describe and compare plastic collected in the gyre? What characteristics about the plastic in the gyre are still unknown and worth investigating further? Materials: Scales for determining mass, metric rulers or meter sticks, Ziploc bags/grocery store bags for collecting and storing debris, plastic gloves for safety and hygiene, masking tape for creating labels. Target Audience: Grades 9-12 Time/Duration: 3, 1 hour classes Target Learning Objective(s)/Concept(s)/Desired Results: Student will be able to: Conduct investigations and communicate findings that are meaningful. Analyze patterns (size, shape) and limitations with respect to categorizing and communication marine debris information. Understand and appreciate the process of collecting and analyzing micro-debris samples from the Southern California Current System through a classroom simulation. Subject: Earth Science/Ecology/Marine Science/Environmental Science Correlating National Science Standards: National Science Standard Science as Inquiry Standards - Understanding about scientific inquiry 5. Science and Technology Standards - Understanding about science and technology 6. Science in Personal and Social Perspectives - Science and technology in local, national, and global challenges - Environmental Quality Correlating California State Standards: INVESTIGATION AND EXPERIMENTATION 1. Scientific progress is made by asking meaningful questions and conducting careful investigations. As a basis for understanding this concept, students should develop their own questions and perform investigations. Students will: a. Select and use appropriate tools and technology (such as computer-linked probes, spreadsheets, and graphing calculators) to perform tests, collect data, analyze relationships and display data. l. Analyze situations and solve problems that require combining and applying concepts from more than one area of science. m. Investigate a science-based societal issue by researching the literature, analyzing data, and communicating the findings. Examples of issues include irradiation of food, cloning of animals by somatic cell nuclear transfer, choice of energy sources, and land and water use decisions in California. Correlating Ocean Literacy Standards: 7. The ocean is largely unexplored. A. Exploration leads to a better understanding of ocean systems. B4. The communication of accurate and timely information allows the public to make informed decisions that promote sustainability of the ocean. [2]

3 In August of 2009, a group of marine biologists and volunteers from the Scripps Institution of Oceanography in La Jolla, California set out to collect data related to the amount and type of plastic marine debris present and its effects on marine life. The Scripps Environmental Accumulation of Plastic Expedition (SEAPLEX) members had approximately 20 days at sea to gather data. The edge of the Central North Pacific Gyre is located approximately 1,000 miles off the shore of California. SEAPLEX researchers had to travel four days just to reach it. prepare for the trip, and used information they obtained to propose future trips. There are also characteristics of the sample and environmental conditions that the researchers commonly document when they describe a sample. This helps The plastic found in the gyre is predominantly pieces no other scientists and bigger than a fingernail in size floating just beneath the researchers to surface of the water. It is difficult to collect, quantify and understand the data describe because the pieces are very dissimilar, they more completely. move with the currents and there is little understood Ocean samples about the origin of the plastic. taken during the day Figure 1: Sample collected aboard the New Horizon during the may be remarkably SEAPLEX cruise. Photo: Lara Scientists often have to use their best judgment when different from Dickens / Teacher at Sea. studying a new phenomenon, place or thing. It is similar samples taken at to packing for a trip when you have little information night. Weather about where you are going and what you will be conditions and seasonal changes are also doing there. Less than 5% of the ocean has important variables to consider when been explored and therefore scientists Nine major collecting or reviewing data. This is an oceanic gyres around that wish to study places like the important consideration when the Central North Pacific Gyre rely on their comparing samples collected over world have become ability to design investigations and long periods of time. accumulation zones for ask meaningful questions to start the plastic debris, process of understanding the gyre The SEAPLEX crew collected the drawing hundreds of tons better. plastic utilizing similar techniques that of plastic into their are used in sampling plankton. They also centers. Researchers develop their sampling plans collected larger plastic from the side of the based on previous sampling events and boat using dip nets when possible. The standards within the discipline. However, sampling and researchers are currently processing hundreds of gyre documenting plastic is a relatively new phenomenon in samples and analyzing their data. However, the the gyre. Preparing for collection and determining the expedition generated new questions about the plastic characteristics of priority to investigate are two very floating in the ocean.. important parts of the research plan. In the case of the gyre, researchers had to use their best judgment to For more information go to the SEAPLEX home page and newsroom link [3]

4 Guidelines/Procedure/Directions: Students gather data and report on litter found on campus. The purpose is to understand the process of inquiry and investigation. The students will design their own sampling criteria and report their findings. Students will also be exposed to published research and the criteria and standards used by experts currently studying plastic debris in the California Current. Day 1: Campus-based litter survey A. Identify the sampling site: In groups of 4 or 5, students will be provided a map of their campus with a portion of the campus designated as their sampling site. Teacher note: It may be more appropriate in some areas to use a local park or parking lot as the sampling site instead of the school. If supervision or security issues are a concern, it may be more appropriate to use the debris collected in the purses and backpacks of the group instead of allowing students to independently explore the campus. Teachers should emphasize that like the gyre, conditions of the campus are not the same throughout. Each group will be sampling from within the campus, but because we are not sampling the exact same place from within the campus our data may vary from group to group. The gyre also has variations due to wind patterns and currents. Sampling in one location of the gyre does not represent data from the entire gyre. Therefore students should study their specific location thoroughly before designing their collection and reporting standards. B. Identify the characteristics of interest and the design collection standards: Students will be responsible for determining the procedure for the collection of the debris. They should consider what will be documented and what environmental conditions are important to note/ measure prior to the collection. Students should design a chart for documenting the samples collected. Teacher note: Students should discuss what they feel is the most appropriate variable to report about the collected debris. In some cases groups may count the pieces of debris, while others may believe the weight of the debris is of more use. The students may wish to compare the sizes of the pieces of debris, the materials the debris are made of, or the volume of the various types of debris. Students should also determine what environmental conditions should be identified with each piece. Time of day, day of week, season, prior to or following a storm, landscaping, relationship to the lunch court, and condition the piece was found are examples of environmental conditions to consider. C. Collect data: Students will be asked to collect debris from within their location for approximately 30 minutes. Teacher note: Teachers may vary the sampling time to meet the needs of the class. Teachers should emphasize that litter comes in many shapes and sizes and that students should not be looking for only the larger items such as water bottles or candy wrappers, but also smaller pieces of litter. It is assumed that most schools are reasonably litter-free and that a large portion of the debris collected will be the size of water bottle cap lids or smaller. D. Analyze Data: Students should identify patterns and group the debris samples in order to quantify their results. Teacher Note: As in professional research, time is a limiting factor. Students should be limited to communicating one or two outstanding patterns or findings. Examples of findings may include that the mass of plastic debris was larger than paper debris collected; more pieces of debris were observed within the lunch court than near the office; landscaping on campus appears to collect smaller pieces of debris than the paved areas; the quantity of food wrappers was larger than the number of beverage containers, etc. Figure 2: Image processing with scanner technology has made it possible to help sort and quantify the composition of samples by hand, separating the microorganisms and the plastic microdebris (Photo credit: Linsey Sala, Scripps Institution of Oceanography and William Miller, Patrick Henry High School teacher, 2010). [4]

5 Day 2: Review current plastic debris practices Researchers are studying the debris floating in the ocean, much like the students are studying the debris found on their campus. Students will be exposed to the rigor of data collection through a guided reading. A. Students will read, Occurrence of plastic microdebris in the southern California Current system. The research publication can be found at the California Cooperative Oceanic Fisheries Investigations website: publications/calcofireports/ vol50/ _gilfillan.pdf B. In groups, students will list the characteristics and measurements that author Lisa Gilfillan used to describe plastic micro-debris, and what remarks she made regarding other published plastic micro-debris studies (Gilfillan et al., 2009). Teacher note: The published paper is an excellent piece to introduce students to technical writing and journals. Teachers may wish to have the class read the entire paper for the experience and exposure to scientific writing and data organization. However it is also appropriate to highlight the following sections and ask students to focus and retrieve information during a guided reading. Allow students time to read the following sections and then pose the questions related to that section. Allow students time to discuss their answers with their group. ABSTRACT: What items and characteristics were the researchers focusing on? Answer: Spatial distribution, concentration, particle size, circularity (roundness), and surface area of the pieces. Follow-up questions: What do each of those terms mean? Did any groups in the class consider measuring the area in which they were sampling? Why is it important to document this? INTRODUCTION: Why is it important to research marine debris? Answer: Because it could have impacts on marine organisms, habitats, and human economies. Follow up question: What did they want to determine? Answer: They were looking at data collected during the winter, over several decades to determine if there had been a change in the amount of plastic present in the ocean. METHODS: What were some of the environmental and collection-specific considerations the researcher had when reviewing archived data? Answer: Data from non-el Nino years were reviewed. It can be assumed that El Nino years would have a substantial increase in onshore rainfall that would lead to a greater quantity of terrestrial debris entering the California Current than in typical winter years. The researcher also identified a manta tow as the sampling device. A manta with a.505 mm net was towed for 15 minutes in the water that was not disturbed by the wake of the boat. Follow up question: Did any of the groups create and sample collecting protocol that was as rigorous as the one used by the researchers? Why is it necessary to be that detailed about the collection of the samples? How long did our class sample the campus? Would the results be different if we sampled for a longer amount of time? DISCUSSION: (Last two paragraphs) What was the difference between plastic concentrations collected by Charles Moore before and after rain events? Would it be important to document weather conditions surrounding a sampling event? Answer: Concentrations doubled. Yes. Follow up question: In the seventh paragraph the researchers noted that they are unable to compare their data with the North Pacific Gyre. They also compare their results to other areas like the Bering Sea. Why is this important to do? What other studies do the researchers suggest would advance our understanding of presence of plastic in the marine ecosystems? Answer: Chemical analysis (type of plastic, toxins adsorbed by plastic, toxins released by plastic, etc.) and the effects on planktonic organisms. At this point teachers should introduce the SEAPLEX website and note the connection between the research paper and the need for more information and the expedition that answered that call. In general, there was a need to know and the SEAPLEX researchers accepted the challenge to study the unknown. [5]

6 Day 3: Communicate findings A. Communicate Findings: Student groups will present their findings to the class using charts and graphs. B. Compare and contrast presentations: The entire class will compare and contrast the presentations, specifically, how the plastic debris was described and quantified. Students will discuss which presentations provided the most relevant and useful information about the survey. C. Reflect on group work: Students will reflect on their pre-collection procedures and identify any concerns they may have with their samples (i.e. small pieces were over-looked, debris had broken down further since collection was done due to handling practices, environment was not noted well enough (landscaping, under lunch tables, near lunch quad, etc.). D. Create a proposal for future research: With the knowledge they have gained from the first survey, students should write a proposal for future research. Proposal should be one page, double-spaced and include the following information: o Why is further research necessary? o How long should the survey take place? o What type of information will be gathered? o How will the data be collected and stored? References: [6]