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DOCUMENT RESUME SE 054 721 ED 404 119 The Living Ocean. TITLE National Aeronautics and Space Administration, INSTITUTION Washington, D.C. NASA-EP-307 REPORT NO Jan 94 PUB DATE NOTE 9p. NASA Teacher Resource Center, Mail Stop 8-1, NASA AVAILABLE FROM Lewis Research Center, 2100 Brookpark Road, Cleveland, OH 44135. Teaching Guides (For Clasdroom Use Guides PUB TYPE Teacher) (052) MFO1 /PCO1 Plus Postage. EDRS PRICE Environmental Education; Grade 9; Grade 10; DESCRIPTORS *Greenhouse Effect; High Schools; *Oceanography; *Photosynthesis; Science Education; Teaching Guides Atmospheres; *Carbon Dioxide; *Phytoplankton IDENTIFIERS ABSTRACT This teaching guide contains information, activities, and discussion questions and answers about oceans for grades nine and ten. The information section covers the following topics: studying global ocean color from space, what can be seen from space, phytoplankton, carbon dioxide, and the greenhouse effect of the earth. (MKR) *********************************************************************** Reproductions supplied by EDRS are the best that can be made from the original document. *********************************************************************** // (' .1., Educational Product Grades 9-10 Teachers FA /11 Ow= U.S. DEPARTMENT OF EDUCATION Office of Educational Research and Improvement EDUCATIONAL RESOURCES INFORMATION CENTER (ERIC) IX This document has been reproduced as received from the person or organization originating it O Minor changes have been made to improve reproduction Quality. Points of view or opinions stated in this docir ment do not necessarily represent official OERI position or policy. 0-17n Zva\i/, i [Fa,) razDW Cer.L, (CO_ [FT° cogifix! &m1mp-i-ocs5 Natio al Aercnauti Administration Spac (cfiQ Planet Mission Office Office Education Studying Global Ocean What We See Life in the Oceans: The Ocean Isn't Just Blue: Color from Space from Space Covering about seventy percent of the We see color when light is reflected by Earth's surface, the oceans are central to the objects around us. White light is made up of a continued existence of life on our planet. The spectrum or combination of colors, as in a oceans are where life first appeared on Earth. rainbow. When light hits the surface of an object, The largest creatures on Earth (whales) and the these different colors can be reflected or ab- smallest (bacteria and viruses) live in the oceans. sorbed in differing intensities. The color we see We rely on the ocean for many things, including depends on which colors are reflected and which food, water, transportation, recreation, minerals, are absorbed. For example, a book that appears and energy. Oceans store energy. When red to us absorbs more of the green and blue ocean currents change, they cause parts of the white light shining on it, changes in global weather patterns and reflects the red parts of and can cause droughts, floods, the white light. and storms. When we look at However, our knowl- the ocean from space, edge of our oceans is limited. we see many different Ships, coastlines, and islands shades of blue. Using provide places from which we instruments that are can observe, sample, and more sensitive than study small portions of oceans. the human eye, we can But we can only look at a very measure carefully the small part of the global ocean this fantastic array of way. We need a better place from 4_ colors of the which to study oceans. ocean. Space provides this place. Satellites Different colors may h2 circling the Earth can survey an entire ocean in reveal the presence less than an hour. These satellites can "look" at and concentration of clouds to study the weather, or at the sea phytoplankton, sediments, surface (when it's not cloudy) to measure the and dissolved organic chemicals. sea's surface temperature, wave heights, and Phytoplankton are small, single-celled direction of waves. Some satellites use radar to ocean plants, smaller than the size of a "look" through the clouds at the sea surface. pinhead. These plants contain the chemical One other important characteristic chlorophyll. Plants use chlorophyll to convert that we can see from space is the color of the sunlight into food using a process called ocean. Changes in the color of ocean water over photosynthesis. Because different types of time or across a distance on the surface provide phytoplankton have different concentrations of valuable information. chlorophyll, they appear as different colors to sensitive satellite instruments such as the In addition, the plants show where pollutants Sea-viewing Wide Field-of-View Sensor (SeaWiFS). poison the ocean and prevent plant growth, and Thus, looking at the color of an area of the ocean where subtle changes in the climatewarmer or allows us to estimate the amount and general colder, more saline or less salineaffect phyto- type of phytoplankton in that area, and tells us plankton growth. Since phytoplankton depend about the health and chemistry of the ocean. upon specific conditions for growth, they Comparing images taken at different periods tells frequently become the first indicator of a change us about changes that occur over time. in their environment. A Little Link Where Does Phytoplankton: Carbon: in a Big Chain It All Go? Why are phytoplankton so important? Besides acting as the first link in the food These small plants are the beginning of the food chain, phytoplankton are a critical part of chain for most of the planet. As phytoplankton ocean chemistry. The carbon dioxide in the grow and multiply, small fish and other animals atmosphere is in balance with carbon eat them as food. Larger animals then eat dioxide in the ocean. During photo- these smaller ones. The ocean fishing synthesis, phytoplankton remove carbon industry finds good fishing spots by dioxide from sea water, and release looking at ocean color images to lo- oxygen as a by-product. This allows cate areas rich in phytoplankton. the oceans to absorb additional carbon dioxide from the Phytoplankton, as atmosphere. If fewer revealed by ocean color, frequently show scientists phytoplankton existed, atmospheric carbon where ocean currents provide nutrients for dioxide would plant growth. increase. Fossil Fuel Emissions nun nun nun nun People Phytoplankton Photosynthesis v-V- 11-V- Agriculture uses CO2 and produces 02. but also a source of CH4 Sedimentary Rocks Livestock CH4) (produce methane The carbon cycle. dioxide acts as a "greenhouse" gas in the atmo- Phytoplankton also affect carbon dioxide sphere, and therefore may contribute to global levels when they die. Phytoplankton, like plants on warming. Sources of carbon dioxide in the Earth's land, are composed of substances that contain atmosphere include decomposition of organic carbon. Dead phytoplankton can sink to the ocean matter (such as trees), the carbon dioxide that floor. The carbon in the phytoplankton is soon animals and people exhale, volcanic activity, and covered by other material sinking to the ocean human activities such as the burning of fossil bottom. In this way, the oceans act as a sink, a fuels and wood. place to dispose of global carbon, which otherwise would accumulate in the atmosphere as carbon No one yet knows how much carbon the oceans and land can absorb. Nor do we know dioxide. Other global sinks include land vegetation how the Earth's environment will adjust to and soil. However, the carbon in these sinks increasing amounts of carbon dioxide in the frequently is returned to the atmosphere as atmosphere. Studying the distribution and carbon dioxide by burning or decomposition. changes in global phytoplankton using ocean Deforestation contributes to the accumulation of color and other tools will help scientists find carbon dioxide in the atmosphere by reducing answers to these questions. vegetation that takes up carbon dioxide. Carbon A Giant The Earth: Greenhouse The Earth is unique to our solar system: it emitted from the Earth is absorbed by the can sustain life. Without the Earth's atmosphere, atmosphere before it escapes into space. Carbon our planet would become extremely cold and dioxide, water vapor, and other gases in the barren of life. The atmosphere consists of atmosphere are responsible for absorbing nitrogen (about 70 percent) and oxygen (about 20 escaping long-wavelength energy. Thus, the Earth keeps some percent). The other ten percent consists mostly of of the heat that would otherwise carbon dioxide, water vapor, and several "trace" have been lost to space. gases such as neon and argon. Like the glass roof and walls of a greenhouse, the Earth's atmosphere keeps its < surface much warmer than it would be without the "greenhouse effect." How? Energy from the sun arrives as short-wavelength radiation (light), while the Earth emits long-wavelength (infrared) energy back into space. The hotter an object is, the shorter the wavelength of the radiation it emits. The short-wavelength sunlight easily pene- Short-wavelength trates the atmosphere and warms the Earth. solar radiation However, some of the long-wavelength energy Atmosphere boundary Long-wavelength Long-wavelength Earth radiation Earth radiation H Earth's surface The greenhouse effect. If a zooplankton, a very small animal type of 2 The concentration of carbon dioxide in the plankton, eats a phytoplankton, generally atmosphere has changed in the past hundred speaking, what happens to the zooplankton and carbon years. Before the Industrial Revolution, the carbon that remained in the phytoplankton? dioxide levels stayed nearly stable for thousands of fossil-fuel- years. Since human beings developed a based global economy and lifestyle, the amount of What is an example of the lowest level of 3 atmospheric carbon dioxide has increased the "food chain" on land? dramatically. This increase means that less long- wavelength energy emitted from the Earth can this can escape to space. Many scientists believe 4 Scientists use two types of satellites to lead to a gradual warming of the Earth, but others study the environment. A geostationary believe that different factors counteract this satellite remains above the same spot on the warming effect. For example, cloud cover reflects Earth's equator from an altitude of about 22,500 sunlight before it ever reaches the Earth, thus miles, and can "see" an entire hemisphere all the reducing the amount of sunlight that reaches the time. A polar-orbiting satellite travels in a Earth's surface. Studying these processes is circular orbit, passing above the North and South difficult, because they are complicated. Ocean Poles while the Earth rotates beneath it. This type color information provides one of the many tools of satellite can "see" details as small as a mile or scientists use to try to find what changes are less. Which of these satellites probably would be occurring, and how they may affect us. better for our ocean color instrument? Would one hurricanes prove better than the other to track and other large weather systems? And Discussion Activities: Questions How do the atmosphere and the ocean 5 interact? There are areas of the ocean with relatively How could global warming affect sea levels? 6 1 large concentrations of nutrients that animals Why is global warming important? and plants use as food substances. In these areas (the plant portion you see a lot of phytoplankton of plankton), especially in the spring. Why do Where do plankton grow? 7 of phyto- some areas have greater amounts plankton? Where would be the best place for deep-sea fishing? 8 Make a greenhouse. Materials needed: Analysis: Two cardboard shoe boxes Discuss the differences you see in the observed temperatures in the two boxes, and why this is Clear plastic wrap happening. Two regular "weather type" thermometers Desk light with 75 watt or larger bulb. Variation: Try replacing the paper towels in each box with Procedure: black paper. Repeat the experiment. What Place some paper towels loosely in the bottom of differences do you note? each shoe box, then lay the thermometer on the towels. Cover the open top of one box with plastic wrap, taped to the side of the box; leave the other box with the top off (open). Place the boxes side by side, and move the desk light so it shines evenly into both boxes. Record the temperature in each box every minute for 10 minutes. Plot the temperatures on a graph with time as the "x" (horizontal) axis and temperature as the "y" (vertical) axis. EP-307 NOTE: The information and activities in this guide are related 1/94 to the poster, The Living Ocean (WAL-145, February 1994). The poster is available at NASA Teacher Resource Centers. Answers 5. Differences in the heating and cooling rates of 1. When wind-driven surface currents carry water land and ocean affect air circulation. Land and deep ocean away from continents, an upwelling of water temperatures rise and fall at different rates water occurs. These cold waters have high because land absorbs and loses heat faster than concentrations of nutrients, leading to phyto- is water does. During the day, hot air rises and plankton growth and creating a highly productive replaced by cooler air. This small-scale circulation fishing area. Ocean plants live.within 200 meters is called a sea breeze, and usually starts three or from the surface where there is sunlight. four hours after sunrise, reaching its peak by early afternoon. At night, the land is cooler than the 2. Most zooplankton migrate to the surface at water because the land has given up its heat to night to feed on phytoplankton, and then sink to the atmosphere. The cool air flows over the greater depths during the day. When zooplankton warmed. This warmer water and rises as it is die, they carry carbon with them as they sink to circulation is called a land breeze, and usually the bottom of the ocean. starts to form in the late evening. It reaches its peak intensity near sunrise. 3. Plants and bacteria are at the bottom of the food chain. Animals that eat grass, such as 6. Global warming may cause sea levels to rise by sheep, belong to higher food web levels. several mechanisms. Temperature increases may regions to cause some of the ice in the polar 4. A polar-orbiting satellite potentially can "see" melt, which would raise sea levels. Higher water everywhere in the world in about two days, and its temperatures also may cause the oceans to orbit is low enough so that it can detect smaller expand. This expansion would cause a sea-level details than a geostationary satellite. It will pass rise. Scientists are studying how global warming time over a certain area once daily at the same would affect sea levels, because a substantial rise of day, which is important for instruments that in the sea level may flood coastal cities and other of ocean use sun illumination for measurements low-lying areas. color or land vegetation. A geostationary orbit hemisphere at the can view almost an entire 7. Plankton [microscopic drifting plants and hurricanes and same time, is able to track animals) live near the ocean surface where there weather systems by making measurements is sunlight. Satellites will see changes in the color used for every half hour or so, and also is of water that indicates growth of ocean plants. meteorological purposes. 9 To PLANET EARTH MISSION e-05(4--/D-1 U.S. DEPARTMENT OF EDUCATION ERIC1 Office of Educational Research and Improvement (0ERI) Educational Resources Information Center (ERIC) I NOTICE REPRODUCTION BASIS This document is covered by a signed "Reproduction Release (Blanket)" form (on file within the ERIC system), encompassing all therefore, or classes of documents from its source organization and, does not require a "Specific Document" Release form. This document is Federally-funded, or carries its own permission to reproduce, or is otherwise in the public domain and, therefore, may be reproduced by ERIC without a signed Reproduction Release form (either "Specific Document" or "Blanket"). (9/92)