Weather's Outer Limits

MATERIALS PER STUDENT

  • copy of reproducibles
  • references with global weather data
    (see Resources)
  • graphing paper
  • small, color-coded stick-on notes
  • 1 or more maps of North America and globe
    (if available for the group)

CONTEXT
Which place on Earth is the hottest? The coldest? The snowiest? The driest? Have students make educated guesses and explain the reasons for their choices. For example, does latitude matter the most? Are places farthest from the equator always the coldest? Are both of the poles very snowy? Why or why not? In this activity, by compiling, graphing, and mapping weather data, students will discover that many variables besides latitude can determine climate.

PREPARATION
Photocopy the reproducibles, one copy per student.

PROCEDURE

  1. As a warmup activity, engage students in a quick game of "Around the World in Eight Minutes." Using a globe or world map, quickly point to different parts of the world at random and ask students to hypothesize what the weather is like in different areas.
  2. Divide the group into teams of 3-4 students each. Assign each team a latitude range from the list below. Each range includes several cities found within the same general latitude.
  • TROPICAL (20° plus or minus from the equator): San Juan, Puerto Rico; Mexico City, Mexico; Quito, Ecuador; Honolulu, HI
  • TEMPERATE 30's: Jacksonville, FL; San Francisco, CA; Kansas City, MO; Denver, CO; Santiago, Chile
  • TEMPERATE 40's: Portland, OR; Boise, ID; Chicago, IL
  • SUBARCTIC (50-65°): Juneau, AK; Dublin, Ireland*; Fairbanks, AK; Edmonton, Alberta
  • ARCTIC AND ANTARCTIC (above 65°): North Pole (Greenland Weather Station); South Pole (Amundsen-Scott Station); Barrow, Alaska; Palmer Station, Antarctic Peninsula
  1. Pass out the reproducibles and discuss the weather data, challenging students to find explanations for seeming incongruities. For example: Why would one city (Omaha) be colder than another located farther to the north (Seattle)? (Answer: the moderating effect of water off of Seattle.) Ask: How does your area compare to the poles?
  2. Using the weather table and other reference materials you have gathered, have teams research similar data for their lists of cities. You may want to focus the research on one or more of these factors: temperature, precipitation, wind, or humidity. If you'd like the students to produce all of the research for this activity, use the weather table as a model only.
  3. Once the teams have gathered and recorded their weather data, challenge them to find explanations for incongruities, then discuss their findings with the entire group.
  4. Challenge each team to plot its data on a map or maps of North America and Latin America (one category of climate data per map). They can also show their findings on simple bar graphs by plotting cities on the horizontal axis, and a single weather variable, such as average annual rainfall or average lowest temperature, on the vertical axis.

* Dublin is included in this list because its climate is particularly temperate despite its latitude (because of the effect of the Gulf Stream).

ASSESSMENT
Ask students to list and discuss the variables that influence climate (latitude, altitude, proximity to an ocean, etc.). Why is Antarctica so much colder and drier than the Arctic, even though the two regions are the same distance from the equator? Evaluate students' responses based on their understanding that proximity to water has a moderating effect on climate; it makes cold regions warmer and warm regions cooler. Ocean currents keep the North Pole at just below freezing, while the temperatures at the South Pole and other inland science stations plunge to Earth's lowest extremes. Also, the high altitude of inland Antarctica means the air is thinner and drier.

EXTENSION
Humans are among the most ill-suited organisms on Earth for extreme weather. An unclothed human starts to shiver at 23°C (73.4°F) and sweat at 27°C (80°F). At -40°C (-40°F) in a 48 kph (30 mph) wind, this same human being will die in less than 30 minutes! How do we compare with polar animals? Have students research the climate ranges of Arctic foxes, polar bears, caribou, and other polar animals. What are the high and low temperatures of their climate range?

Resources

Poles Apart: Parallel Visions of the Arctic and Antarctic, by Galen Rowell (University of California; 1995). Contrasting photos illustrate differences between the poles.

Automated Weather Service (2-5 Metropolitan Ct., Gaithersburg, MD 20878; 800-544-4429; ). An online program for schools to collect and share local weather data.

CNN ( and many other online publications provide searchable, up-to-the-hour weather data for areas around the globe. Search the web for "current weather" or select "weather" on your web browser menu for a list of URLs.

Everything Weather CD-ROM by The Weather Channel (208.134.241.130/education/usamap) features 500 U.S. cities and more than 200 international cities. Isoline maps and graphs included.

The National Weather Service ( and is a fount of national weather and climate data and has numerous web sites on the local level. Its data base includes 300 U.S. cities and 85,000 world cities.

The World Almanac, Information Please Almanac, Guinness Book of World Records, and similar books include useful climate data, such as a lists of average annual snowfall by city.

Polar Connection: Good and Cold

"News Item: While some parts of the United States sweltered under record hot temperatures last summer, the South Pole recorded its coldest July ever. The average temperature for July at the U.S. Amundsen-Scott South Pole Station was -66° Celsius (-87°F), breaking the 22-year-old record by two full degrees. What was the reaction from scientists over wintering at the station? "These very cold days provide the best conditions for astronomical observations—clear skies and low wind. On the down side, power usage is at a maximum and vehicle operation is almost impossible."

—South Pole Meteorolgist Matt Wolf, one of 28 people spending the winter at the station

Courtesy NSF/National Science Foundation