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Math Concept Reader
Math Concept Reader #TLA@EPEKJ JP=N?PE?= ca62xs_lay_061207ad_am.indd 1 1/11/07 11:51:59 AM DIGITAL FINAL PROOF Expedition: Antarctica by Aenea Mickelsen ca62xs_lay_061207ad_am.indd 4 1/9/07 9:09:15 AM DIGITAL FINAL PROOF Copyright © Gareth Stevens, Inc. All rights reserved. Developed for Harcourt, Inc., by Gareth Stevens, Inc. This edition published by Harcourt, Inc., by agreement with Gareth Stevens, Inc. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system, without permission in writing from the copyright holder. Requests for permission to make copies of any part of the work should be addressed to Permissions Department, Gareth Stevens, Inc., 330 West Olive Street, Suite 100, Milwaukee, Wisconsin 53212. Fax: 414-332-3567. HARCOURT and the Harcourt Logo are trademarks of Harcourt, Inc., registered in the United States of America and/or other jurisdictions. Printed in the United States of America ISBN 13: 978-0-15-360204-7 ISBN 10: 0-15-360204-X 1 2 3 4 5 6 7 8 9 10 175 16 15 14 13 12 11 10 09 08 07 Math Concept Reader #TLA@EPEKJ JP=N?PE?= by Aenea Mickelsen ca62xs_lay_061207ad_am.indd 1 1/11/07 11:52:01 AM DIGITAL FINAL PROOF ' Ms. Milburn’s students return to the classroom from lunch. Outside, it is a hot autumn day, so the students are glad to sit down and cool off. Ms. Milburn tells the students that she has been searching the Internet for a scientific expedition they could follow. A scientific expedition is a planned journey, usually to a remote area, for a scientific purpose. Sometimes scientists communicate with students through the Internet while they are on an expedition. They answer questions and talk about the research they are conducting. Ms. Milburn explains that even though she could not find a current expedition that the class could participate in, they still can plan a virtual expedition to Antarctica. Jacob wants to know why anyone would consider going to this cold, remote continent in the Southern Hemisphere. Ms. Milburn asks the class if anyone can answer that question. Someone suggests that scientists can gather interesting data about Antarctica’s extreme weather conditions. Scientists can also study climate issues that affect the entire world. For example, some scientists worry that rising temperatures in Antarctica could melt much of the continent’s ice and raise the level of the planet’s oceans. !D=LPAN .H=JJEJC=J #TLA@EPEKJ ca62xs_lay_061207ad_am.indd 2 1/11/07 11:52:05 AM DIGITAL FINAL PROOF ( Antarctic explorers travel with sleds as the sun sets. Ms. Milburn asks her class two questions. What information do we need in order to plan an expedition? Would it be similar to planning a winter trip to the local mountains? Christopher says that it would be better to go to Antarctica in June or July, because summer is not as cold as winter. Ms. Milburn shows the class a map of the world and reminds the students that Antarctica is in the Southern Hemisphere. The seasons in the Southern Hemisphere are opposite of the seasons in the Northern Hemisphere. So while the students may think of June and July as the hottest months of the year, they’re actually among the coldest for Antarctica. Since it is such a hot day, many students think that cooling off in Antarctica sounds like a great idea. The class realizes that to plan an expedition, they need to know more than when the seasons occur. They need temperature information in order to make an informed decision about when to plan their virtual expedition. They also agree that gathering information about wind and rain will be helpful. ca62xs_lay_061207ad_am.indd 3 1/11/07 11:52:08 AM DIGITAL FINAL PROOF ) These people pack their supplies before starting their expedition in Antarctica. Next, Ms. Milburn asks the class what supplies they might need for an expedition. For instance, would the winter coats they wear where they live keep them warm in Antarctica? Would they need special sleeping bags for the frigid nights? Ms. Milburn shows the class a Web site with information about expeditions. On one journey led by explorers Ann Bancroft and Liv Arnesen, scientists had to fit all of their supplies onto a sled that could hold no more than 250 pounds. They packed food, cooking supplies, health supplies, and other equipment onto the little sled. The scientists had to choose carefully, taking the supplies they needed while staying under the weight limit. To get started, Ms. Milburn divides the class into three groups. The first group will research Antarctica’s climate and temperatures. The students in this group have to find the best month, in terms of weather, to launch an expedition to Antarctica. The second group will research wind and rain data. The third group will research clothing and equipment needed for an expedition. ca62xs_lay_061207ad_am.indd 4 1/11/07 11:52:11 AM DIGITAL FINAL PROOF * Cuyamaca Mountains Average Daily Temperature Month 10 15 20 25 5 0 Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. Temperature (in Degrees Celsius) Ms. Milburn begins by sharing some local weather data with the class. She shows the students a graph that displays temperature data for the nearby mountain range. Looking at the local data will give the class something familiar to which they can compare the Antarctica data. Ms. Milburn tells the students that the lowest temperature ever recorded in the local mountains is ¯22 degrees Celsius. That temperature was recorded in February 1998. Together, she and the students look at the data to see what else they can learn. As expected, the class determines that the winter months of December, January, and February are the coldest months in their local mountain range. The average temperature in January is about 4 degrees Celsius. The average temperature in July, meanwhile, is the warmest at about 21 degrees Celsius. Compared to January, July is about 17 degrees warmer. In March, the average temperature is about 7 degrees Celsius, which is 3 degrees warmer than January. ca62xs_lay_061207ad_am.indd 5 1/11/07 11:52:12 AM DIGITAL FINAL PROOF + The first group of students looks for temperatures in Antarctica. They focus on two different locations, McMurdo Base and Mawson Station. McMurdo Base, run by the United States, is the starting point for many expeditions in Antarctica. Scientists study geology, marine biology, meteorology, and more. Mawson Station is run by Australia. Some of the scientists at Mawson Station are researching how the climate of Antarctica affects the rest of the world. As the group searches for temperature data, they find some amazing information. There is a Russian station called Vostok (vahss-TOKE). This station is very close to the South Pole and holds the record for the coldest recorded temperature on Earth at about ¯89 degrees Celsius. Scientists recorded the temperature on July 21, 1983. The students use an equation to calculate that the record temperature at Vostok is 67 degrees colder than the lowest temperature recorded in their local mountains. ¯22 – ¯89 = ¯22 + 89 = |¯89| – |22| = 89 – 22 = 67 !D=LPAN 0AOA=N?DEJC ca62xs_lay_061207ad_am.indd 6 1/11/07 11:52:14 AM DIGITAL FINAL PROOF , Average Temperature (in Degrees Celsius) McMurdo Base Average Daily Temperature Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. High 0 ¯6 ¯14 ¯17 ¯18 ¯18 ¯21 ¯22 ¯20 ¯15 ¯6 ¯1 Low ¯5 ¯11 ¯20 ¯24 ¯26 ¯26 ¯30 ¯31 ¯28 ¯22 ¯12 ¯6 Mawson Station Average Daily Temperature Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. High 3 ¯1 ¯7 ¯12 ¯14 ¯14 ¯15 ¯16 ¯15 ¯10 ¯3 2 Low ¯3 ¯7 ¯13 ¯17 ¯19 ¯20 ¯21 ¯22 ¯21 ¯16 ¯9 ¯3 The students examine the average high temperatures in the two locations over a period of twelve months. At McMurdo Base, the highest temperature occurs in January and is 0 degrees Celsius. At Mawson Station, temperatures average about 3 degrees Celsius in January. That makes it 3 degrees warmer than McMurdo. Next the students wonder which month is usually the coldest. They quickly determine that August is the coldest month at both locations. The average high temperature at McMurdo Base in August is ¯22 degrees Celsius. At Mawson Station, the average high temperature is about ¯16 degrees Celsius. Mawson is about 6 degrees Celsius warmer in August. At McMurdo Base, the average low temperature in August is ¯31 degrees Celsius. That is about 9 degrees warmer than the average low temperature at Mawson Station. ca62xs_lay_061207ad_am.indd 7 1/11/07 11:52:15 AM DIGITAL FINAL PROOF - Atlantic Ocean Pacific Ocean McMurdo Base Indian Ocean Southern Ocean Ross Ice Shelf A N TA R C T I C A Mawson Station Davis Neumayer Vostok WILKES LAND South Pole Ronne Ice Shelf This map shows the continent of Antarctica. The second group of students looks for information about the wind at McMurdo Base and Mawson Station. They find that researchers often record the wind speed at these two locations. The group looks at those averages for each month of the year. At McMurdo, the highest average wind speed in March is about 27 km/h (kilometers per hour). At Mawson Station, March wind speeds are about 38 km/h. The difference in wind speeds in March is about 11 km/h. June has the highest average wind speed at about 43 km/hr. At McMurdo Base, the average wind speed in June is 25 km/h. 43 – 25 = 18 The difference in wind speeds in June is about 18 km/h. Next the group finds the two locations on a map of Antarctica. They learn that Mawson Station is located on the coast of the Indian Ocean, while McMurdo Base is on the Pacific Ocean. They wonder if the different locations might affect the wind speeds. ca62xs_lay_061207ad_am.indd 8 1/11/07 11:52:17 AM DIGITAL FINAL PROOF [...]... bathing comes from melting ice, it takes a lot of energy to produce it With all the facts the class has gathered, they are now well prepared to undertake their virtual expedition into Antarctica The class is ready to take a virtual expedition into Antarctica ca62xs_lay_061207ad_am.indd 15 1/11/07 11:52:44 AM DIGITAL FINAL PROOF Glossary Celsius a metric scale for measuring temperature in which the... Degrees Celsius) Weight (in Pounds and Ounces) ¯40 5 pounds ¯29 4 pounds 4 ounces ¯18 3 pounds 11 ounces ¯7 2 pounds 4 ounces Now the group looks for some of the equipment that will be needed for the expedition The students find pictures of tents in Antarctica, as well as photographs of buildings The group assumes that because it’s so cold in Antarctica, the scientists do not sleep outside all of the... students review the data they collected Ms Milburn asks the groups to present their findings before the class The first group reports their findings on the temperatures in Antarctica They recommend planning an expedition for January, because the average temperature in Antarctica that time of year is around ¯2 degrees Celsius That is 24 degrees warmer than in August, when the average temperature is about ¯26... in January is about 27 km/h That is about 16 km/h less than the average wind speed in June They also report that rain is not an issue in Antarctica They agree that January would be a good month for an expedition ca62xs_lay_061207ad_am.indd 12 1/11/07 11:52:30 AM DIGITAL FINAL PROOF Jackets and other gear are important for people who work in the extreme Antarctic temperatures The third group tells the... imagining a day with zero hours of daylight Antarctica is so far away from the equator that daily sunshine is an issue That information gives them another reason to pick January as an ideal month for an expedition ca62xs_lay_061207ad_am.indd 14 1/11/07 11:52:41 AM DIGITAL FINAL PROOF Ms Milburn congratulates the groups for gathering relevant information Now the class will organize the data they found... for temperature ratings for jackets Temperature ratings will tell them just how cold it can be outside before they’ll feel it when they’re wearing a jacket Not all of the jackets that look suitable for expeditions come with temperature ratings The students gather the information on temperature ratings for jackets They find that one jacket is rated to ¯23 degrees Celsius, a second one to ¯26 degrees Celsius, . Explore/yourexpedition.com; p. 2: Jupiter Images Corporation; p. 4: Bancroft Arnesen Explore/yourexpedition.com; p. 6: Jupiter Images Corporation; p. 9: NOAA; p. 11: Bancroft Arnesen Explore/ yourexpedition.com;. while they are on an expedition. They answer questions and talk about the research they are conducting. Ms. Milburn explains that even though she could not find a current expedition that the. to plan an expedition, they need to know more than when the seasons occur. They need temperature information in order to make an informed decision about when to plan their virtual expedition.