Investigating Temperature Extremes in the USA Using ArcGIS Online
Your Name: _________________
Summary
This activity uses ArcGIS Online, a Web-based
Geographic Information System (GIS)
(www.arcgis.com) as a tool for analyzing the
extreme high and low temperatures of the
USA from a spatial perspective.
Level and Disciplines
This activity is written for secondary level but
can be modified for the primary or university
levels. It can be used in formal or informal
educational settings and in an independent
or whole-class format. It can be used in
geography, environmental studies, biology,
or earth science courses.
Map of extreme temperatures in the USA. This is the
central investigation and the map that will be
examined in this activity.
Skills and Content
Skills and content involved: 1) Analyzing spatial patterns and processes; 2) Investigating high and low
temperature extremes and their relationship to latitude, altitude, seasons, proximity to coasts, and
other factors.
Prerequisites
No previous experience with GIS is necessary. However, (1) the geographic perspective is important,
and (2) a background in the topic investigated would be helpful; at a minimum, a short discussion on the
processes and phenomenon studied in each investigation should be held at the beginning; such as
“What factors are important in the climate and weather of the USA? What influence do seasons have
on the location of and value of temperature extremes?”
Computer and Time Requirements
(1) Web browser; (2) A decent Internet connection. Can be run in a computer lab setting, with students
bringing their own tablets/laptops/devices, or with 1 computer in front of the class with a projector.
Time Required: 2 to 3 hours. 57 questions.
Data Description
Data layers include January and July 2011 extreme temperatures, and a topographic map showing
topography, and cultural features such as states, cities, and highways. The temperature extreme data
Investigating Temperature Extremes in the USA Using ArcGIS Online - Page 1 of 7
Author: Joseph J. Kerski – jkerski@esri.com
Copyright © 2012, Esri. http://edcommunity.esri.com
comes from USA Today, on: http://www.usatoday.com/weather/wext.htm. These questions and the
data sets were compiled with the grateful assistance of a stellar secondary school student.
Introduction
Access ArcGIS Online (www.arcgis.com/home). Start a new map and search for “temperature extremes
thematically mapped owner:jjkerski”. Be sure to accurately enter this entire search string. In the
resulting search window, click below the thumbnail map that appears and select “open in ArcGIS.com
map viewer.” The map should open in your web browser. Alternatively, go directly to the map at the
following URL: http://bit.ly/NNh4Eo
Map Description
This map is a dynamic map displayed in a web-based GIS called ArcGIS Online. It shows the locations of
all of the places during January 2011 and July 2011 that recorded a high or low temperature extreme in
the USA for each of the 31 days in January and the 31 days in July for that year. In other words, for
example, on 15 January, the high temperature in the USA occurred in Santa Ana, California, and the low
temperature on that date occurred in two places: In Northway, Alaska, and also in Chicken, Alaska.
Therefore, the cities of Santa Ana, Northway, and Chicken all are symbolized appropriately on this map.
Note that in the rare instance where a high or low occurred that was not listed as a geolocatable city or
town, the nearest city or town was used.
The January 2011 high and low temperatures are symbolized by red and blue dots, respectively. The
July 2011 high and low temperatures are symbolized by red and blue suns (respectively). As you click on
the locations where an extreme temperature was recorded, the top right corner of the resulting popup
box contains an arrow if that specific location experienced a temperature extreme more than once. To
see the additional extreme temperature(s) for that location, click on that arrow.
Investigating January Highs and January Lows
1) Examine the map as displayed in ArcGIS Online. Do any of the locations showing high and low
temperature extremes surprise you? Why or why not?
2) What spatial patterns do you notice about the January high temperatures in the USA?
3) Give at least 2 reasons why these patterns may exist.
4) What spatial patterns do you notice about the January low temperatures in the USA?
5) Give at least 2 reasons why these patterns may exist.
6) Zoom to Hawaii. Did Hawaii experience any high or low temperature extremes during January? Does
this surprise you? Why or why not?
Investigating Temperature Extremes in the USA Using ArcGIS Online - Page 2 of 7
Author: Joseph J. Kerski – jkerski@esri.com
Copyright © 2012, Esri. http://edcommunity.esri.com
7) How many of the 50 states were represented with an extreme temperature (high or low) in January?
Is the state where you live represented?
Comparing January Highs and Lows to July Highs and Lows
8) What pattern do you notice about the July high temperatures in the USA?
9) Give at least 2 reasons why these patterns may exist.
10) What pattern do you notice about the July low temperatures in the USA?
11) Give at least 2 reasons why these patterns may exist.
12) Why do you suppose Hawaii set records in January but did not set any records in July?
13) Why do many January high extreme temperatures occur near the coasts, yet in July, very few if any
extremes occur near the coasts?
14) Are you surprised that not all the January lows were in Alaska? Why do you think some were not?
15) In Alaska, the January lows were typically inland, while the July lows were often near the coast.
Even though they were both lows, compare the temperatures. What influence does the coast have on
the temperatures?
16) Does this extreme temperature map give enough information to give you an idea of a location’s
average year-round temperature? Why or why not?
17) Zoom to Noatak, Alaska, where a January and July low both occurred. What do you think the
average annual temperature is in Noatak?
18) Some of the July lows occurred in Arizona. Does this surprise you or not? Explain why.
19) Which region of the country (Southwest, Northwest, Mountain West, Midwest, New England,
South Central, Southeast, Alaska, or Hawaii) has the highest high temperatures? Why do you think this
is?
20) What key differences do you note between the spatial pattern of highs and lows in January versus
the highs and lows in July? What are the reasons for these differences?
Examining Climate, Latitude, Altitude, and Proximity to Coasts
21) Compare the high and low temperature extremes between states that have a wetter climate and
states that have a drier climate. What do you notice? Do you have any ideas why this might be?
Investigating Temperature Extremes in the USA Using ArcGIS Online - Page 3 of 7
Author: Joseph J. Kerski – jkerski@esri.com
Copyright © 2012, Esri. http://edcommunity.esri.com
22) What difference does proximity to the ocean have on high temperatures? On low temperatures?
Why?
23) What difference does elevation have on temperatures in the USA? Why?
24) What differences exist between the value of Alaska extreme temperatures and those in the
continental USA or in Hawaii? Why?
25) What does the fact that some of the coldest temperatures in Alaska were not in the far north of the
state, but in the interior, and also not in the highest elevations, but in the lowlands, tell you about the
influence of the sinking of cold air in basins versus latitude?
26) Except for Florida and Wisconsin, there were no temperature extremes east of the Mississippi River
in January or July. Why do you think there were very few temperature extremes east of the Mississippi
River?
27) Can you find a place where a “tie” in the high or low temperatures occurred? There are many ties
on this map. Find one. It might take awhile, but remember to click through the arrows in the popup
boxes; also, the symbols that are bolder than others have ties.) Even some some 5-way ties exist in
Kansas and Oklahoma. Some cities to look include Stanley, ID, Hutchinson, KS, Stillwater and Duncan,
OK, Truckee, CA, and Kona, HI. Remember to click through all the data. To find cities, use the “find
address or place” search box in the upper right.
28) Explain the following statement in the context of this data: Latitude matters.
29) Why did some of the lowest temperatures in January occur south of the northernmost states?
30) Explain the following statement in the context of the data: Altitude matters.
31) Did extreme low temperatures gradually warm up as January progressed? Why or why not?
The Extreme of the Extremes
32) What was the highest temperature in all of January 2011 in the entire USA? In what location did
this temperature occur? Did this temperature occur once or multiple times?
33) What was the highest temperature in all of July 2011 in the USA? In what location did this
temperature occur? Did this temperature occur once or multiple times?
Investigating Temperature Extremes in the USA Using ArcGIS Online - Page 4 of 7
Author: Joseph J. Kerski – jkerski@esri.com
Copyright © 2012, Esri. http://edcommunity.esri.com
Data Recording
Think about the placement of thermometers in relationship to buildings, pavement, in the shade vs. in
the direct sunlight, wind, and other factors.
34) What factors do you think influences the temperature recorded by individual thermometers? What
steps could be taken to ensure that all of the temperatures were taken with uniform instruments and
placement of those instruments?
Actual versus “Felt” Temperature
35) Think about your own experiences outside. What factors make the temperature feel hotter or
colder than the actual temperature reading?
36) Of any of the hottest temperatures on your map, where do you think it actually felt hottest? Of any
of the coldest temperatures, where do you think it actually felt coldest?
Cities and Extreme Temperatures
Examine large cities on your map. You may need to reference an external data set or map if you need
help in determining if a city has over 1,000,000 people.
37) Did any city over 1,000,000 people experience a high or low extreme in temperature during January
or July 2011?
38) Would you say that more cities are located in areas where low extreme temperatures occur, or are
there more cities located in areas where high extreme temperatures occur? Why?
39) Which 2 cities over 1,000,000 people are closest to the low temperature extremes?
40) Which 2 cities over 1,000,000 people are closest to the high temperature extremes?
41) Were most high temperatures near big cities or not? How might proximity to large urban areas
affect the temperature of the surrounding region?
42) Can you pick out any heat waves or cold snaps where several cities clustered together shared some
hot or cold days during a particular week? Where did these heat waves or cold snaps occur? As one
example, note the high temperatures in July 2011 in Oklahoma. Do some research on this Oklahoma
2011 heat wave and describe it in 2 sentences.
43) Did the city where you live (or a city in which you are near to or have visited) set any temperature
records during the months in this dataset?
Investigating Temperature Extremes in the USA Using ArcGIS Online - Page 5 of 7
Author: Joseph J. Kerski – jkerski@esri.com
Copyright © 2012, Esri. http://edcommunity.esri.com
Your Personal Reflections
44) How would you classify the climate of the city in which you live?
45) If your city did not set a record high or low temperature during the month, what is the distance
from your city to the nearest high temperature and the nearest low temperature?
46) Have you ever experienced a "record temperature" day? What was your experience like?
47) Do you think the temperature extremes affect daily life more or less today than they did 100 years
ago? Why? Be sure to support your answer.
48) Would you rather live in a cold climate or a hot climate? Why? Give at least 2 reasons.
49) Do you think living in a cold climate or a hot climate uses more energy per person? Explain.
50) Based on analyzing the distribution of cities on the map, do you think more people in the USA live
where high temperature extremes occur frequently or do more people live where low temperature
extremes occur frequently?
51) Do you think that people living in cities that set the low temperature record in January ever
experience hot days during the year? Why or why not? Do you think that cities that set the high
temperature record in January ever experience cold days during the year? Why or why not?
52) Are there differences in the climate between the cities in Alaska, Minnesota, and Colorado where
the cold temperatures occurred in January? If so, what are they? Why do these differences occur?
53) Are there differences in the climate between the cities in Texas, Florida, and Hawaii where the hot
temperatures occurred in January? If so, what are they? Why do these differences occur?
Synthesis
54) Name two things you have learned about temperature extremes, weather, climate, seasons, or any
other content through the above investigations.
55) Name two things you have learned about maps and GIS through any of the above investigations.
56) How has the spatial perspective about temperature extremes influenced your understanding of it?
57) If time permits, use the presentation mode in ArcGIS Explorer Online to create a presentation of
your own choosing where you explain what you have learned about a specific aspect about the extreme
temperatures. Give your presentation to your peers, save it, and share it with others.
Investigating Temperature Extremes in the USA Using ArcGIS Online - Page 6 of 7
Author: Joseph J. Kerski – jkerski@esri.com
Copyright © 2012, Esri. http://edcommunity.esri.com
Additional Exploration
If you compiled the data from other years and mapped it, do you think the results would be the same as
the 2011 data you examined in this activity? Why or why not?
Using data from the USAToday website, work (alone or with a partner or group) to add the high and low
temperatures of January and July for another year. Create a CSV file containing the data. It should have
the following format:
Day,Month,Year, Temp (F), City, State, Notes
1,Jan,2011 A.D.,83,Kona,HI,"Tie w/ Kahului, HI"
1,Jan,2011 A.D.,83, Kahului, HI,"Tie w/ Kona, HI"
2,Jan,2011 A.D.,83, Kona, HI,
3,Jan,2011 A.D.,83, Kona, HI,
Add your newly created data to the map you have been working with. What patterns are the same and
what is different? How does this change the answers to some of the questions in this lesson? To save
the map with your added data, you will need to have an account on ArcGIS Online and be logged into
that account.
Compile the high and low temperatures for a different set of 2 months of the year; for example, April
and October, so that you can examine spring and fall.
You have explored many aspects of temperature extremes from a spatial perspective, but much more
could be done. Write your own question about temperature extremes or about weather and climate,
investigate it, and answer it!

Investigating Temperature Extremes in the USA Using ArcGIS Online - Page 7 of 7
Author: Joseph J. Kerski – jkerski@esri.com
Copyright © 2012, Esri. http://edcommunity.esri.com