LAB MODULE 9: CLIMATE
Note: Please refer to the GETTING STARTED lab module to learn how to maneuver through and answer the lab questions using the Google Earth() component.
KEY TERMS
After successfully completing this module, you should be able to recognize and describe these terms:
Anthropogenic / Climatology / Köppen-Geiger climate classificationCarbon / Dendrochronology / Proxy data
Climate / Fossil fuels / Rainshadow effect
Climograph / Greenhouse gas / Seasonality
Insolation / Growth rings (tree rings, annual rings) / Weather
LAB LEARNING OBJECTIVES
After successfully completing this module, you should be able to do the following:
· Distinguish between weather and climate
· Identify and describe geographic factors influencing climate
· Explain how these factors influence climate
· Describe the various categories of the Köppen climate classification scheme
· Interpret a climograph
· Apply the Köppen climate classification to various locations given temperature and precipitation data
· Compare various climate classification maps
INTRODUCTION
This lab module examines climate. Topics include the geographic distribution, patterns, and processes associated with Earth’s climates, climate classification schemes, climographs, climate change, and reconstructing historical climate patterns using dendrochronology. The module starts with four opening topics, or vignettes, which are found in the accompanying Google Earth file. These vignettes introduce basic concepts of climate. Some of the vignettes have animations, videos, or short articles that will provide another perspective or visual explanation for the topic at hand. After reading the vignette and associated links, answer the following questions. Please note that some links might take a while to download based on your Internet speed.
Expand the INTRODUCTION folder and then double-click and select Topic 1: Introduction.
Read Topic 1: Introduction.
Question 1: Looking at the image, what are the general climate (temperature and precipitation) conditions for this area?
A. Cold and wet
B. Hot and dry
C. Hot and wet
D. Cold and dry
Read Topic 2: Factors Affecting Climate.
Question 2: Why are there no clouds on the leeward side of the island in the satellite image?
A. Intense drought on the leeward side of the island
B. Ocean currents inhibit cloud formation on leeward side
C. Leeward side is a rainshadow with no clouds forming
D. Lack of vegetation lowers humidity and thus hampers cloud forming
Read Topic 3: Climate Classification.
Question 3: Why are climate normals computed every 10 years?
A. To smooth out the year-to-year variations
B. Because data are only available for that time period
C. Because data are suspect beyond that time period
D. Because that is what weather reports on TV use
Read Topic 4: Human Interaction.
Question 4: What proxy data do scientist use to reconstruct past climates?
A. Ice cores, tree rings, carbon14 dating
B. Pollen remains, ocean sediments, tree rings
C. Carbon 14 dating, ocean sediments, ice cores
D. Glacier lengths, pollen remains, carbon 14 dating
Collapse and uncheck INTRODUCTION.
GLOBAL PERSPECTIVE
In this section, you will identify climate at the global scale using the Köppen-Geiger Classification System. Remember, scale is an important concept in geography because some patterns can be seen better at the global (coarse, small) scale compared to the local (fine, large) scale.
Expand GLOBAL PERSPECTIVE and then double-click and select Köppen-Geiger Map. To close the citation, click the X in the top right corner of the window.
Main Climate / DescriptionA / Tropical, Equatorial
B / Arid, Dry
C / Warm, Subtropical
D / Cold, Continental
E / Polar
Precipitation
W / Desert
S / Steppe
f / Fully humid
s / Summer dry
w / Winter dry
m / monsoonal
Temperature
a / Hot summer
b / Warm summer
c / Cool summer
d / Extremely continental
h / Hot arid
k / Cold arid
F / Polar front
T / Polar tundra
Table 1. Climate descriptors.
The Köppen-Geiger classification system, developed by Wladimer Köppen and revised by Rudolph Geiger, is based on the annual and monthly averages of precipitation and temperature. The climates are based around five broad climate regions:
· Ttropical (A)
· Deserts (B)
· Mesothermal (C)
· Continental (D)
· Polar (E)
These are refined by a second, lowercase letter which accounts for seasonal characteristics relating to temperature and precipitation, while the third, lowercase letter further distinguishes the climate by location (subtropical versus midlatitude). See Table 1 for a list of climate letters and their descriptions.
Doubleclick and select Example. When you arrive at your destination, click on the location in the Google Earth 3D Viewer to display the Köppen-Geiger climate classification. To close the classification box, click the X in the top right corner of the window. Use the climate descriptors in Table 1 to describe the climate class. To help, an example has been done for you. Repeat this process for next four locations.
Example Question:
Location: Tripoli, (Libya)
Köppen-Geiger classification: Csa
Köppen-Geiger description: hot and dry subtropical summer, (C=warm, subtropical; s=summer dry; a=hot summer).
Doubleclick and select Moscow, Russia.
Question 5: Köppen-Geiger classification:
A. Dfb
B. Dfc
C. Dfa
D. Cfb
Question 6: Köppen-Geiger description
A. Humid continental, mild summer
B. Subarctic
C. Humid continental, hot summer
D. Marine west-coast
Doubleclick and select Johannesburg, RSA.
Question 7: Köppen-Geiger classification:
A. Cwa
B. Cfb
C. Bsk
D. Cwb
Question 8: Köppen-Geiger description:
A. Marine west-coast
B. Humid subtropical, hot summer
C. Cold midlatitude steppe
D. Marine dry winter, mild summer
Doubleclick and select Galapagos Islands, Ecuador.
Question 9: Köppen-Geiger classification:
A. Bwk
B. Bwh
C. Bsk
D. Bsh
Question 10: Köppen-Geiger description:
A. Cold midlatitude desert
B. Cold midlatitude steppe
C. Hot low-latitude desert
D. Hot low-latitude steppe
Doubleclick and select Kuala Lumpur, Malaysia.
Question 11: Köppen-Geiger classification:
A. Am
B. Af
C. Aw
D. Ac
Question 12: Köppen-Geiger description:
A. Tropical Desert
B. Tropical rainforest
C. Tropical Savanna
D. Tropical Monsoon
Collapse and uncheck GLOBAL PERSPECTIVE
CLIMOGRAPHS
Expand the CLIMOGRAPHS folder.
Doubleclick and select Köppen-Geiger Map. To close the citation, click the X in the top right corner of the window.
Double-click and select Rome Climograph.
A climograph is a graphic representation of monthly precipitation and temperature averages for a given locale (in this case, Rome, Italy) over the span of a year. Climographs provide a graphic snapshot of the Köppen-Geiger classification.
Each letter designation in the Köppen-Geiger classification system has climatic parameters. Using Rome as an example:
· For the first letter designation:
o …is not an A climate because its coolest month (January) is colder than 18C.
o …is not a B climate because less than 70 percent of the rainfall occurs in the summer (June-August).
o …is a C climate as the temperature of warmest month is ≥ 10 degrees Celsius (July), and temperature of coldest month is < 18 degrees Celsius but > –3 degrees Celsius (January).
· For the second letter designation of C climates, the choices are f, s, and w. In the case of Rome, the second letter designation:
o …is not f, because each month needs 60mm of precipitation. As we can see in the climograph, the months of May to August do not have an average of 60mm of precipitation.
o …is not w, because the winter months are not the dry season.
o …is s, because the summers are the dry season, with the driest month (in July, at 16 cm) having less than 1/3 of the precipitation in the wettest winter month (in October, at 113 cm). Thus far, we know Rome is a Cs.
· For the third letter of a Cs climate, the choices are a and b. In the case of Rome, the third letter designation:
o …is not b. The b classification also has a mean monthly temperature over 22 degrees Celsius for its warmest month, but has 4 months with a mean temperature below 10 degrees Celsius. The climograph shows that Rome has only 3 months in which the mean monthly temperature is below 10C.
o …is a, as it has a mean monthly average temperature over 22 degrees Celsius for its warmest month and does not meet the climate parameters of a b climate.
By using the climograph to assess the climatic parameters, we have determined that Rome has a Csa Köppen-Geiger classification. The name of this class is hot and dry summer subtropical, also known as hot Mediterranean climate. To note, this is the same climate as the earlier example with Tripoli, Libya.
Using the Köppen-Geiger Map folder and the climographs, determine the climate classification and the associated temperature and precipitation patterns for the following cities (Hint: Remember that when it is winter in the Northern Hemisphere, it is summer in the Southern Hemisphere, and vice versa).
Table 2 lists the characteristics of the Köppen letter designations.
First Letters / Derivation / Distinguishing CharacteristicsA / Alphabetical / Mean temperature each month >18°C (64°F).
B / Alphabetical / Mean annual precipitation <76 cm (30 in.).
C / Alphabetical / Mean monthly warmest temperature >10°C (50°F) in warmest month.
Mean monthly coldest temperature between 18°C and -3°C (65°F-27°F) in coldest month.
D / Alphabetical / Mean temperature >10°C (50°F) in 4-8 months.
E / Alphabetical / Mean temperature <10°C (50°F) in all months.
H / Alphabetical / Significant climate changes due to variation in altitude.
Second Letters / Derivation / Distinguishing Characteristics
F / German feucht, “moist” / 6 cm (2.5 in.) of mean rainfall in each month.
M / Monsoon / Only 1-3 months with mean rainfall <6 cm (2.5 in.).
S / Summer dry / Summer dry season, with driest month having <1/3 the mean precipitation of wettest winter month.
S / Steppe (semi-arid) / Mean annual precipitation in low latitudes is 38-76 cm (15-30 in.); whereas, it is between 25-64 cm in midlatitudes.
No distinct seasonal trend in either latitude range.
T / Tundra / At least 1 month with mean temperature between 0°10°C (32°-50°F).
W / Winter dry / Winter dry season, with 3-6 months of <6 cm (2.5 in) of mean rainfall in A climates. In C and D climates, the driest month has <1/10 the mean precipitation of the wettest summer month.
W / German wüste, “desert” / Mean annual precipitation <38 cm (15 in.) in low latitudes and <25 cm (10 in.) in midlatitudes.
Third Letters / Derivation / Distinguishing Characteristics
A / Alphabetical / Warmest month has mean temperature >22°C (71.6°C)
B / Alphabetical / Warmest month has mean temperature <22°C (71.6°F), but has 4 months with mean temperature >10°C (50°F).
C / Alphabetical / Warmest month has mean temperature <22°C (71.6°F); fewer than 4 months with mean temperature >10°C (50°F).
D / Alphabetical / Same as c, but coldest mean monthly temperature <-38°C (-36.4°F).
H / German heiss, “hot” / Mean annual temperature >18°C (64.4°F).
K / German kalt, “cold” / Mean annual temperature <18°C (64.4°F).
Table 2. Köppen Climate Designations.
Click Beijing Climograph.
Question 13: Referring to Table 2, what is the Köppen-Geiger classification for Beijing, China?
A. Dwa
B. Dwb
C. Dfc
D. Dwc
Question 14: Referring to Table 2, describe the temperature and precipitation patterns as seen in the climograph.
A. Humid with cold, wet winters
B. Hot, wet summers, cold dry winters
C. Humid with mild wet winters
D. Cool with wet summers and warm dry winters
Click Bangkok Climograph
Question 15: Referring to Table 2, what is the Köppen-Geiger classification for Bangkok, Thailand?
A. Am
B. Af
C. Aw
D. As
Question 16: Referring to Table 2, describe the temperature and precipitation patterns as seen in the climograph.
A. Tropical, no dry season
B. Tropical, summer monsoon
C. Tropical, winter rains
D. Tropical, no wet season
Click Lima Climograph.
Question 17: Referring to Table 2, what is the Köppen-Geiger classification for Lima, Peru?
A. Bwh
B. Bwk
C. Bsk
D. Bsh
Question 18: Referring to Table 2, describe the temperature and precipitation patterns as seen in the climograph.
A. Cool, wet summers
B. Mild, dry summers
C. Cool, dry winters
D. Mild, wet summers
Click Cairo Climograph.
Question 19: Referring to Table 2, what is the Köppen-Geiger classification for Cairo, Egypt?
A. Bwh
B. Bwk
C. Bsk
D. Bsh
Question 20: Referring to Table 2, describe the temperature and precipitation patterns as seen in the climograph.
A. Warm, wet summers
B. Hot, dry summers
C. Warm, dry winters
D. Hot, wet summers
Collapse and uncheck CLIMOGRAPHS.
COMPARING CLASSIFICATIONS
As noted in Topic 2 in the Introduction, there are a number of geographic factors influencing climate. Below are several pairs of cities that have similar geographic characteristics. Answer the following questions as they pertain to each pair of cities.
Expand the COMPARING CLASSIFICATIONS folder. Doubleclick and select Köppen-Geiger Map. To close the citation, click the X in the top right corner of the window.
Doubleclick and select Portland and Milwaukee.
Locations: Portland, OR (45 30N, 122 40W) and Milwaukee, WI (43 02N, 87 55W) have roughly the same latitude.
Question 21: Portland, OR is located within which Köppen-Geiger class?
A. Cfb
B. Cfa
C. Csa
D. Csb
Question 22: Milwaukee, WI is located within which two Köppen-Geiger classes?
A. Dfa/Dfc
B. Dfc/Dwc
C. Dfa/Dfb
D. Dwa/Dwc
Question 23: What is the primary geographical factor that explains this difference?
A. Longitude
B. Elevation
C. Continentality
D. Sun angle
Doubleclick and select Walvis Bay and Maputo.
Locations: Walvis, Bay, Namibia (23 56S, 14 31E) and Maputo, Mozambique (25 58S, 32 35E) are both coastal cities.
Question 24: Walvis, Bay, Namibia is located within which Köppen-Geiger class?