Table of Contents
Part 1: Climate Graphs Activity
Part 2: Texas Climate Handout
Maps for transparencies:
a. Texas Average Annual Temperature
b. Texas Average Annual Precipitation
c. Texas Climate Regions
Base Map:
Major Cities in Texas
Activity 1
CLIMATE GRAPHS AND CLIMATE REGIONS OF TEXAS
Background: Climate graphs (sometimes called climagraphs) summarize many kinds of environmental
conditions. Geographers, and others, use climate graphs to understand climate and phenomena that rely
upon climate such as vegetation. Climate graphs provide clues to weather conditions in particular places.
They can help answer questions such as: How much does it rain and/or snow? What time of the year is
wet/dry? What kind of vegetation can grow? (Trees grow naturally in wetter places; grasses are the rule if
precipitation supply and demand are nearly the same; desert plants survive if temperatures are high when
there is little rain), What months see a moisture deficit and requires people to store water and irrigate?
What months show a moisture surplus, rivers form, and flood prevention may be necessary?
Objective: Your objectives are
1) to be able to summarize some basic principles of Texas climate,
2) to be able to describe the characteristics of the climates of Texas, and
3) to be able to identify and explain the factors which shape patterns of climate in Texas.
Assignment: The National Weather Service has divided Texas into ten divisions, regions of similar
geography and climate (see the accompanying map). Data on the average monthly temperature (degrees F)
and precipitation (inches) for each climate division is provided. Your task is to:
1. Make a climate graph for each set of data. Ten climate graphs are provided. You may choose to do this
on a computer or use graph paper.
2. Match the climate graph to the correct climate division using deductive reasoning. Label each climate
graph by division name. Hint: Calculate the total precipitation and the average annual temperature for
each region to help the decision making process.
3. Below each climate graph write 2-3 sentences explaining your deduction. What was your reasoning in
making your selection? Be sure to use the factors listed below in your reasoning process, that is,
latitude, continentality, seasonality, and quantity. Two additional factors may help you to make your
decision: vegetation and elevation.
Hints: To make a climate graph, plot the data on precipitation as a bar graph; plot temperature as a line
graph. An example is shown below:
Climagraph, Moline Illinois
5 80
4.5 PPT 70
4 Temp
60
3.5
3 50
2.5 40
2 30
1.5
20
1
0.5 10
0 0
J M M J S N
Factors Which Influence Climate
Here are some questions to ask yourself to help match places with the climate graphs. Be sure to use these
factors in the explanation of your deductive process.
Latitude. Looking at the temperature curve and the average temperature (Calculate and enter on the data
table below), check the distance from the equator. Warmer temperatures in the winter mean a location
closer to the equator.
Continentality. Water is slow to heat up and slow to cool down; land cools and heats quickly. Places that are
close to water will be moderated by its effects. Thus, temperatures at the beach are cooler in the summer
and warmer in the winter. The "maritime" effect decreases with distance away from the coast. Locations
far inland have more extreme temperatures: hot summers, cold winters.
Quantity. How much precipitation falls? What is the general trend east to west in Texas concerning
precipitation? What is the general trend from north to south?
Seasonality. When does the climate division receive its precipitation? Remember, it rains for three
reasons: orographic ppt (because of mountains), convection ppt (e.g., afternoon thunderstorms), and frontal
ppt (e.g. Northers, hurricanes). Watch the Weather Channel for a while to get the hang of this.
Elevation. Higher places are cooler and more moist than places lower in elevation.
Vegetation. What kind of plants grow in each climate division? Forests need rain, grasses survive on half
as much rain as trees, deserts even less. Apply what you know about vegetation to help decide climate
patterns. But remember, vegetation is an EFFECT of a climate, not the CAUSE of it.
CLIMATIC DATA FOR TEN PLACES, TEXAS, 1996
J F M A M J J A S O N D Total PPT
/ Average
Temp.
Data 1
Temperature 53.0 57.4 57.3 67.4 79.2 81.7 84.6 82.6 79.2 71.4 64.0 58.4
Precipitation 2.12 .76 .74 1.8 .59 7.51 1.83 9.06 7.55 2.92 2.47 3.12
Data 2
Temperature 55.5 60.8 60.8 72.2 83.7 86.4 88.0 85.6 82.1 74.3 65.9 57.7
Precipitation 0.00 .13 .21 .76 .71 1.4 1.34 4.39 2.65 .99 .98 .48
Data 3
Temperature 46.5 54.0 53.5 64.3 79.8 82.5 82.8 78.5 73.0 64.9 55.2 48.0
Precipitation .14 .10 .03 .49 .45 2.27 1.54 3.22 2.59 .16 .77 .02
Data 4
Temperature 37.1 43.8 44.9 57.7 73.4 77 78.4 75.6 67.3 58.8 47 40.2
Precipitation .09 .11 .16 .21 1.57 3.05 4.70 4.48 2.93 .66 1.10 .20
Data 5
Temperature 43.3 51.6 52.1 63.4 78.3 80.9 85.3 81.3 73.9 65.9 54.6 49.1
Precipitation .87 .28 1.83 2.49 1.83 2.75 3.15 5.94 4.74 3.10 5.80 1.21
Data 6
Temperature 52.6 58 57.5 69.0 80.8 83 85.9 83.9 79.1 71.8 63 56.6
Precipitation .08 .38 .89 1.69 .55 3.78 .91 6.07 4.78 1.02 2.46 1.88
Data 7
Temperature 60.4 63.6 63.7 72.4 81.5 84.4 86.6 84.9 82.8 75.8 70.1 63.7
Precipitation .04 .09 .30 .86 .44 1.51 .10 4.29 3.98 4.91 .64 .47
Data 8
Temperature 46.4 53.2 54.1 65.8 79.7 82.8 85.4 82.1 75.3 66.3 56.7 49.3
Precipitation .06 .26 .58 1.67 2.09 1.49 1.22 4.63 4.12 2.68 2.77 .89
Data 9
Temperature 45.8 52.6 52.4 63.6 77.5 79.8 84.1 80.5 74.1 65.9 55.8 51.2
Precipitation 1.60 .53 1.73 3.55 1.68 3.85 4.19 6.85 5.37 2.79 5.63 3.47
Data 10
Temperature 41 48.9 49.6 62.3 78.2 80.8 83.8 80.1 71.7 63.2 51.1 46.1
Precipitation .33 .08 .90 .87 1.73 2.74 2.58 4.58 3.86 1.39 2.42 .03
Weather Highlights, 1996
Late February: unseasonably high temperatures over entire state
Early April: blizzard in Midland, Abilene
May-June: Drought conditions state wide with record breaking heat and extremely low ppt. Heat causes evaporation to eat away at
available water supplies—water supplies not replenished by rainfall because of extremely dry conditions.
Late August: Hurricane Dolly hits Tampico, MX and significantly affects TX weather with much needed ppt almost state wide.
Name: _________________________________
Period: __________ Date:__________________
Texas Climate
Instructions:
For this activity you will be using maps of Texas average annual precipitation and Texas average
annual temperature to determine climate regions.
Prediction:
1. Look at the outline map of Texas titled “Major Cities in Texas”.
What city do you think has the coldest average annual temperatures? _______________
What city do you think has the warmest average annual temperatures? _____________
What city do you think has the highest amount of precipitation? ___________________
What city do you think has the lowest amount of precipitation? ___________________
Comparison:
Get the transparencies with the titles “Texas Average Annual Temperature” and “Texas Average
Annual Precipitation” from your teacher.
2. Place the “Texas Average Annual Temperature” map over the “Major Cities” map. Look at
the overall temperature patterns. Describe the pattern you see.
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
http://agsss.tamu.edu 1
3. Rank the cities from the highest temperature to lowest temperature.
City Ranking
Temperature: Highest to Lowest
Abilene
Amarillo
Austin
College Station
Dallas/Ft.Worth
Eagle Pass
El Paso
Galveston
Houston
Longview
San Angelo
San Antonio
4. Of the factors affecting temperature listed in your book, which do you think has the most
influence in Texas: latitude, altitude, distance from large bodies of water, or ocean
currents? Why?____________________________________________________
________________________________________________________________________
________________________________________________________________________
5. Now look at the overall precipitation patterns by placing the “Texas Average Annual
Precipitation” map over the “Major Cities” map. . Describe the pattern you see.
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
http://agsss.tamu.edu 2
6. Rank the cities from the highest precipitation to lowest precipitation.
City Ranking
Precipitation: Highest to Lowest
Abilene
Amarillo
Austin
College Station
Dallas/Ft.Worth
Eagle Pass
El Paso
Galveston
Houston
Longview
San Angelo
San Antonio
7. Of the factors affecting precipitation listed in your book, which do you think has the most
influence in Texas: prevailing winds or mountain ranges? Why? __________________
________________________________________________________________________
________________________________________________________________________
Overlay:
Place the “Texas Average Annual Temperature” map over the “Major Cities in Texas” map. Then
place the “Texas Average Annual Rainfall” map over those.
8. What relationship do you see between the patterns? ______________________________
________________________________________________________________________
________________________________________________________________________
http://agsss.tamu.edu 3
Climate Region Delineation:
Overlay the “Texas Climate Regions” map with the “Major Cities Map”.
9. What Climate Region do each of the cities fall in?
City Climate Region
Abilene
Amarillo
Austin
College Station
Dallas/Ft.Worth
Eagle Pass
El Paso
Galveston
Houston
Longview
San Angelo
San Antonio
10. Now return to the Climate Graphs you created in class. Use the information you have just
discovered to assign the name of the Climate Region to each Climate Graph.
Analysis:
Based on what you’ve learned in class and this assignment answer the following questions.
11. What type of weather would you expect Austin to have if it was in a valley?_____________
__________________________________________________________________________
__________________________________________________________________________
12. If there was a mountain range between Houston and College Station, what weather changes
would you expect in College Station?____________________________________________
__________________________________________________________________________
__________________________________________________________________________
http://agsss.tamu.edu 4