Can Global Warming Cause Global Cooling? Climate Change in Greenland and the North Atlantic 3 By Betsy Youngman and David Smith Guiding Question Learning Objectives How fast is the Greenland ice sheet Students will be able to: melting, and what are the possible • describe the rate of change of the impacts of that change? Greenland ice sheet and the impacts on the salinity in the North Atlantic Project Duration • explain the possible impact of climate Three to five 45-minute class periods change on the global thermohaline ocean circulation Grade Level • relate ocean currents to terrestrial Grades 8-12+ (ages 13-18) climate classification Subjects • Environmental Science • Earth Science • Oceanography Project 3 of Investigating Your World with My World GIS • www.natgeoed.org/MyWorldGIS Copyright 2012 National Geographic Society. Photographs by Betsy Youngman (top left); George F. Mobley (top right); Chuck Tomlin, My Shot (bottom) Mobley (top right); Chuck Tomlin, (top left); George F. Photographs by Betsy Youngman Copyright 2012 National Geographic Society. TEACHER INSTRUCTIONS Can Global Warming Cause Global Cooling? Climate Change in Greenland and the North Atlantic By Betsy Youngman and David Smith Connections to National Standards How fast is the Greenland NATIONAL SCIENCE EDUCATION STANDARDS, GRADES 9-12 ice sheet melting, and what • Standard A-1: Abilities necessary to do scientific inquiry are the possible impacts of • Standard F-5: Natural and human-induced hazards • Standard F-6: Science and technology in local, that change? national, and global challenges NATIONAL GEOGRAPHY STANDARDS • Standard 1: How to Use Maps and Other Geographic Overview Representations, Tools, and Technologies to Acquire, Students use GIS and other media to explore a critical Process, and Report Information From a Spatial area of climate change research: glacial melting and its Perspective potential impact on the ocean currents. In Lesson A, • Standard 14: How Human Actions Modify the Physical students are introduced to the Greenland ice sheet and Environment observe the increase in melting on the ice sheet. Lesson • Standard 18: How to Apply Geography to Interpret the B of the activity introduces students to the great oceanic Present and Plan for the Future conveyor belt and the critical deep-water formation zones that drive this system. Lesson C examines the question: Vocabulary what will happen to climate if the oceanic conveyor belt • glacier, noun—a mass of ice that originates on land, slows? usually having an area larger than one tenth of a square kilometer; many believe that a glacier must show Background some type of movement; others believe that a glacier Evidence shows increased melting of glaciers in can show evidence of past or present movement. The Greenland. The addition of fresh water to the North Greenland ice sheet is a thick glacier that covers most Atlantic threatens to alter the ocean’s salinity in the North of the island of Greenland. Atlantic region. The North Atlantic is also home to a key • glacial mass balance, noun—the difference between the area of the oceanic conveyor belt, where colder, denser accumulation (gain) and ablation (loss) of glacial ice water sinks and initiates the conveyor. Given the role that and snow. A glacier that has negative mass balance is salinity plays in maintaining the oceanic conveyor belt, in retreat, or decline. Usually calculated on an annual a decrease in salinity due to the addition of fresh water basis. (which is less dense) from the melting of the Greenland • salinity, noun—amount of salt dissolved in a liquid; ice sheet threatens to slow or shut down the oceanic saltiness. conveyor belt. If the conveyor shuts down, it will no longer bring warm, ocean waters from the south to areas of Northern Europe. Since the ocean plays an important role in the local climate balance, this could lead to a dramatic drop in local temperatures for Northern Europe. Can Global Warming Cause Global Cooling? • Teacher Instructions • Page 27 TEACHER INSTRUCTIONS Teaching Strategies Extending the Learning In this chapter there are three separate GIS lessons; each • Show one of the following the short videos: “NOVA: takes approximately one class period to complete. Science Now—Fastest Glacier” or “Scientific American The lessons are: Frontiers XV: Hot Planet—Cold Comfort.” Both videos • Lesson A: Is Greenland Melting? are available online. Have a discussion about what • Lesson B: Is the Salinity in the North Atlantic students observe in the videos. Changing? • Have students complete research about the present • Lesson C: How are Climate and Ocean Currents trends in the melting of the Greenland Ice Sheet. Some Interlocked? resources are listed below: —NASA Global Climate Change Key Indicators: http:// You will need to allow time for an introduction to the topic climate.nasa.gov/keyIndicators/index.cfm#landIce and a wrap-up discussion. —NSIDC Atlas of the Cyrosphere: Begin with a class discussion of the key question. Include http://nsidc.org/data/atlas/ in the discussion the topics of climate, climate change, —NASA Annual Accumulated Melt over Greenland, and climate change research. Use a globe or map to 1979 through 2009: http://svs.gsfc.nasa.gov/vis/ introduce students to the location of Greenland and the a000000/a003700/a003721/index.html Atlantic Ocean. Remind students that they are working • Learn more about remote sensing and the study with the data that is currently being collected by the of the Cyrosphere on the ICEsat page. scientists. Many scientists around the world are working http://icesat.gsfc.nasa.gov/ together to understand climate change and its possible • Help students learn more about climate change outcomes. Like the scientists, students may have to think research by showing segments from the video, about how the data sets are connected. Climate change “Earth: The Operators Manual”: has many features and fingerprints; in order to see the http://earththeoperatorsmanual.com/for_educators connections one needs to think like a detective! Engage students in the excitement about Greenland’s Additional Resources changing ice sheet. Read recent news and share images • MapMaker 1-page Maps: http://education. of melting glacial ice from the June 2010 National nationalgeographic.com/education/mapping/outline- Geographic Magazine article, “Greenland: Ground Zero for map/?ar_a=1 Global Warming.” The article is linked in the Resources • National Geographic Climate Change Collection: Global section, below. Warming. http://education.nationalgeographic.com/ education/topics/global-warming/?ar_a=1 After the whole-class introduction, have students work in • National Snow and Ice Data Center’s resources for pairs at computers while using My World GIS. Give each educators, scientists and citizens: http://nsidc.org/ pair the Student Instructions, the Answer Sheet, and a • Details of Ice Velocities Around the 2000-meter Traverse in blank outline map of the world. See Resources for a link Greenland: http://nsidc.org/data/parca/data.html#parca-9 to blank maps. • NASA Images and trends of melting ice: Students will use three project files in this chapter: http://www.nasa.gov/externalflash/globaliceviewer/ climate_change_greenland.m3vz • Woods Hole Oceanographic Institute’s in-depth analysis climate_change_oceans.m3vz of the changes in the North Atlantic. climate_change_impacts.m3vz —“A River Runs Through It: Chronicling the Currents of the North Atlantic” http://www.whoi.edu/page. do?pid=12455&tid=282&cid=2557 —Abrupt Climate Change: Should We Be Worried? http://www.whoi.edu/page. do?pid=12455&tid=282&cid=9986 Can Global Warming Cause Global Cooling? • Teacher Instructions • Page 28 TEACHER INSTRUCTIONS Data Dictionary Additional information about each of the layers used in this project • Greenland AWS Locations: Greenland Automated • Avg River Discharge (m^3/s): River discharge Weather Stations. Located on the Greenland ice shows the amount of fresh water entering the sheet. Source: Konrad Steffen—University of ocean Colorado CIRES • Salinity Research Sites: Oceanographic research • Glacier Velocity Gates: Locations marked with buoys used in salinity, temperature, and current geospatial coordinates. Used in monitoring the velocity research. Credit: Ruth Curry—Woods Hole motion of the ice sheet. Source: Bea Csatho—Ohio Oceanographic Institute State University • Dense Water Formation Sites: Locations where • Greenland ice sheet (km): Ice sheet location and deep ocean currents form due to changes in extent. Credit: National Snow and Ice Data Center salinity and temperature • 1992—2002 Greenland Melting Extents: Summer • Avg Annual Surface Temp and Salinity of Oceans: melting area and extent. These are locations Surface temperature and salinity of the ocean where liquid water can be detected on top of the • Elevation and Sea-floor Bathymetry: Shows ice sheet. Recorded by satellite. Source: Russell elevation of Earth’s surface features Huff—University of Colorado CIRES • Generalized Ocean Conveyor Belt: Thermohaline • Continents: Polygon layer with continental circulation pattern boundaries. Source: ESRI • Global Wind Pattern: Generalized pattern of winds • Buoy Locations: Oceanographic research buoys over oceans used in salinity, temperature, and current velocity • Surface Currents: Generalized pattern of surface research. Source: Bob Dickson—Centre for currents driven by winds over oceans Environment, Fisheries and Aquaculture Science • Climate Classes (Simple): Regions of similar (CEFAS) climate (precipitation