climate classification activity-teacher
DESCRIPTION
Activity guide for classifying local climate using the Koppen-Geiger climate classification system. Teacher GuideTRANSCRIPT
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What is your climate classification?
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What is your climate classification?
Background
Climate is the average of the day-‐to-‐day weather over a long duration. Generally, this long duration refers to 30 years or more. Two weather elements are extremely important to climate: temperature and precipitation. Wladimir Köppen (1900) developed a climate classification system for world climate types using annual and seasonal patterns of temperature and precipitation as well as vegetation types. In 1954, Rudolf Geiger updated Köppen’s system and made it available as a world map. Today, this system, known as the
Purpose To help students become familiar with the Köppen-‐Geiger climate classification system by looking at long-‐term (30 year) temperature and precipitation data. Students will also understand that climates can be broadly classified using a system that is based upon specific variables – air temperature and precipitation. Overview Students will become familiar with the Köppen-‐Geiger climate classification system. The students will calculate simple statistics and analyze a long-‐term (30 year) temperature and precipitation dataset. They will examine/explore the relationship between temperature and precipitation to determine the climate classification for their location. Student Outcomes Students will be able to:
• Understand the importance of consistent and accurate data collection
• Synthesize and analyze long-‐term (30 year) data to determine the local climate classification
• Understand how air temperature and precipitation data are used to describe climate.
Time This activity may take 1-‐2 45-‐60 minute class periods if the data set identification, data entry, calculations, and working through the relationships are all done in class. This activity could also be homework. Level Grades 5-‐12 Materials and Tools
• Access to the internet and/or printed long-‐term monthly mean air temperature and precipitation data
• Calculator or appropriate computer application, such as Excel
Preparation The teacher may want to identify/locate a long-‐term (30 year) temperature and precipitation data before starting the activity Prerequisites Basic mathematics skills – calculation and understanding of means, addition, multiplication, and inequalities Graphing skills – interpretation of graphs Climate Literacy Principles
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Köppen-‐Geiger climate classification system, is widely used and identifies 31 different climatic regions.
There are five major types of climate classifications: Equatorial (A), Arid (B), Warm Temperate (C), Snow (D), and Polar (E). Each type can then be further classified by precipitation and temperature conditions. This results in 31 different climate classifications. A climate classification can provide a great understanding that temperature and precipitation are both important to climate.
Students can better appreciate their local climate by working with long-‐term temperature and precipitation data to classify their local climate, or the climate of another location on Earth. To do this, they will need access to a long term (30 year) dataset, complete the simple calculations, and work through the temperature-‐precipitation relationships in this activity.
Köppen-Geiger Climate Classification Category Descriptions
Here we provide a general description of each climate in the Köppen-‐Geiger climate classification system. Climate classification is given by two or three letters: the first the main classification and the second and optional third are the sub-‐classifications.
Climate Classfication
Full Name
Description
Af Equatorial rainforest, fully A climate which sees all twelve months humid with temperatures greater than +18°C
and rainfall more than 60 mm.
Am Equatorial monsoon Area characterized by all twelve months having a mean temperature of greater than or equal to +18°C and a mean annual accumulated precipitation greater than or equal to 25 x (100-‐Pmin) where Pmin is the month with
the least amount of precipitation, in mm.
As Equatorial savannah with Area characterized by all twelve months having dry summer a mean temperature of greater than or equal to +18°C and a summer month with precipitation
less than 60 mm.
Aw Equatorial savannah with Area characterized by all twelve months having dry winter a mean temperature greater than or equal to +18°C and a winter month with precipitation less than 60 mm.
BWk Arid desert cold A climate whose mean annual temperature
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is less than +18°C and is too dry to support
most plants.
BWh Arid desert hot A climate whose mean annual temperature is greater than or equal to +18°C and is too dry
to support most plants.
BSk Arid Steppe cold A climate whose mean annual temperature is less than +18°C and is too dry to support a forest but not dry enough to be a desert,
usually consisting of grassland plains.
BSh Arid Steppe hot A climate whose mean annual temperature is greater than or equal to +18°C and is too dry to support a forest but not dry enough to be a desert, usually consisting of grassland
plains.
Cfa Warm temperate fully humid A climate where the coldest month is warmer with hot summer than -‐3°C but colder than +18°C and precipitation is generally the same throughout the year. This climate is usually found in the interior of continents or on their east coast,
usually between 25° and 35° latitude.
Cfb Warm temperate fully humid A climate where the coldest month is warmer with warm summer than -‐3°C but colder than +18°C and precipitation is generally the same throughout the year. This climate is usually found inland in the interior of continents or on their east coast,
usually between 35° and 45° latitude.
Cfc Warm temperate fully humid A climate where the coldest month is warmer with cool summer than -‐3°C but colder than +18°C and precipitation is generally the same throughout the year. This climate is usually found inland in the interior of continents or on their east coast, usually between 45° and 55° latitude, but may
extend to 65° latitude.
Csa Warm temperate with dry, A climate where the coldest month is warmer
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hot summer than -‐3°C but colder than +18°C and summers are dry and hot. This climate is usually found
inland on western sides of continents.
Csb Warm temperatuer with dry, A climate where the coldest month is warmer warm summer than -‐3°C but colder than +18°C and summers are dry and mild. This climate is usually found closer to the coast on western sides of continents.
Csc Warm temperate with dry, A climate where the coldest month is warmer cool summer than -‐3°C but colder than +18°C and summers are dry and cool. This climate is usually found on the western coasts of continents, where they
are influenced by cold ocean currents.
Cwa Warm temperate with dry A climate where the coldest month is warmer winter and hot summer than -‐3°C but colder than +18°C and winters are dry. This climate is also characterized by hot, humid summers and is usually found on the
interiors of continents or on their east coast.
Cwb Warm temperate with dry A climate where the coldest month is warmer
winter and warm summer than -‐3°C but colder than +18°C and a noticeable difference between the dry winters
and rainy summers. This climate is usually
found in the highlands of some tropical countries.
Cwc Warm temperate with dry A climate where the coldest month is warmer winter and cool summer than -‐3°C but colder than +18°C and a noticeable difference between the dry winters and rainy summers. This climate is usually found in the
highest elevations of some tropical countries.
Dfa Snow with fully humid A climate where there is at least one month hot summer colder than -‐3°C and precipitation is generally the same throughout the year, and summers can get very hot. This climate is usually found
between 35° and 45° latitude.
Dfb Snow with fully humid A climate where there is at least one month
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warm summer colder than -‐3°C and precipitation is generally the same throughout the year. This climate is usually found between 45° and 55° latitude,
but may extend up to 60° latitude.
Dfc Snow with fully humid A climate where there is at least one month cool summer colder than -‐3°C and precipitation is generally the same throughout the year. This climate is found even further toward the poles, usually between 55° and 65° latitude, but may extend
up to 70° latitude.
Dfd Snow with fully humid A climate where there is at least one month extremely continental colder than -‐3°C and precipitation is generally generally the same throughout the year. This climate is found only in eastern Siberia and is notable for its extreme winter cold.
Dsa Snow with dry, hot summer A climate where there is at least one month colder than -‐3°C and summers are dry and hot. This climate is usually at high elevations near locations that are warm temperate with dry,
hot summers.
Dsb Snow with dry, warm summer A climate where there is at least one month colder than -‐3°C and summers are dry and warm. This climate is usually at even higher elevations near locations that are warm
temperate with dry, hot summers.
Dsc Snow with dry, cool summer A climate where there is at least one month colder than -‐3°C and summers are dry and mild. This climate is usually at even higher elevations near locations that are warm
temperate with dry, hot summers.
Dsd Snow with dry summer, A climate where there is at least one month extremely continental colder than -‐3°C and winter is wetter than summer. This climate is found only in eastern Siberia and is notable for its extreme winter
cold.
Dwa Snow with dry winter, A climate where there is at least one month
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and hot summer colder than -‐3°C with dry winters and wet summers. This climate is usually found in
eastern Asia between 35° and 45° latitude.
Dwb Snow with dry winter, A climate where there is at least one month and cool summer colder than -‐3°C with dry winters and wet summers. This climate is usually found in eastern Asia between 45° and 55° latitude, but
may extend up to 60° latitude.
Dwd Snow with dry winter, A climate where there is at least one month extremely continental colder than -‐3°C with dry winters and wet summers. This climate is found only in eastern Siberia and is notable for its extreme winter
cold.
EF Polar frost A climate where each month is colder than +10°C, but the warmest month is still warmer than 0°C. This climate is generally found on the northern edges of Northern Hemisphere
continents and surrounding islands.
ET Polar tundra A climate where each month is colder than 0°C. This climate is generally found in Antarctica and inner Greenland.
What to do and how to do it
• Obtain long-‐term (30 years) monthly mean temperature and precipitation data • Perform the appropriate calculations and determine the climate classification using
the example data below (New Dehli, India) as a model of what to do. • Complete the worksheet and discuss the results.
How to determine your Köppen-Geiger Climate Classification
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The following is an example of how to determine a Köppen-‐Geiger climate classification from a long term (30 year) temperature and precipitation data set. Climatological data from New Dehli, India is used as an example.
Figure 1. Map of India, showing the location of New Delhi (Source: worldtravels.com)
The temperature and precipitation data from New Dehli (Table 1) show the monthly mean air temperature and monthly accumulated precipitation averaged over 30 years (1979-‐2009, from NCDC). This is also shown in graph form (Figure 2).
Month Temp (°C) Precip (mm) January 13.53 18.58 February 16.98 21.53 March 22.52 22.78 April 28.88 10.47 May 32.33 36.61 June 32.72 84.02 July 30.87 184.49
August 29.99 190.25 September 29.06 115.45 October 25.32 12.59 November 19.54 3.97
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December 14.65 9.42
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Figure 2. 30 year mean air temperature (°C) and total precipitation (mm) (Source: NCDC)
In order to determine the major climate classification for New Dehli, the following values will need to be determined or calculated and filled in on Table A (see below).
1. Annual temperature (Tann) a. Add up each monthly mean temperature and divide by 12 (the number of
months in a year). 2. Coldest month’s temperature (Tmin) 3. Warmest month’s temperature (Tmax) 4. Accumulated annual precipitation (Pann)
a. Add up each monthly accumulated mean precipitation 5. Precipitation threshold (Pth)
a. The precipitation threshold is designed to determine the relationship between precipitation and evaporation. This is also known as a dryness index and is dependent upon when precipitation falls during the year.
b. To determine the precipitation threshold, look at the monthly precipitation on the climograph (Figure 2.) or look at the data table (Table 1) and determine if most (more than 70% of Pann) of the location’s precipitation falls in either the summer, winter, or if it is spread throughout the year.
i. If most of the precipitation falls in the summer, the precipitation threshold is calculated by multiplying the annual temperature by 2 and adding 28
ii. If most of the precipitation falls in the winter, the precipitation threshold is calculated by multiplying the annual temperature by 2
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iii. If precipitation is spread throughout the year, the precipitation threshold is calculated by multiplying the annual temperature by 2 and adding 14
c. In the case of New Dehli, India, notice that most of the precipitation falls in June, July, August, and September, which is summer. This is case i.
For the New Dehli, India example, Table A would be completed as follows:
Value Tann Annual Temperature (°C) 24.70 °C
Tmin Temperature of Coldest Month (°C) 13.58 °C Tmax
Temperature of Warmest Month (°C)
32.72 °C Pann Accumulated Annual Precipitation
(mm) 710.17 mm
A Pth Precipitation Threshold (mm) 77.40 mm
Once table A is complete, your main classification can be determined by using the Köppen-‐Geiger Climate Classification Key, which is based on relationships of temperature and precipitation. These relationships compare the temperature of the warmest month to a set value, such as 10°C. The main climate classification is based on Köppen’s observations of what types of plants are favored for growth in a specific climate.
After determining the main climate, further temperature and precipitation conditions can be used to determine your sub-‐climate classification(s). For the second letter, the relationship between when the precipitation falls and how much falls is important. The following values will determine which season, if any, is wetter than another.
1. Amount of precipitation in the wettest month in the winter (Pwmax) 2. Amount of precipitation in the driest month in the winter (Pwmin) 3. Amount of precipitation in the driest month in the summer (Psmax) 4. Amount of precipitation in the driest month in the summer (Psmin) 5. Are there at least four months with temperature greater than 10°C? Answer yes or
no.
After examining the data, the values should be filled in on Table B (see below). For the New Dehli India example, Table B would be completed as follows:
Value Pwmax Amount of precipitation in wettest winter month (mm) 21.53 mm Pwmin Amount of precipitation in driest winter month (mm) 9.42 mm Psmax Amount of precipitation in wettest summer month (mm) 190.25 mm Psmin Amount of precipitation in driest summer month (mm) 84.02 mm
B Are there at least 4 months with T greater than 10°C (yes, no) Yes
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Once Table B is complete, the first sub-‐climate classification can be determined by using the Köppen-‐Geiger Climate Classification Key, which looks at the amount of precipitation that falls in summer and winter. The final sub-‐climate classification can be determined by looking at temperatures throughout the year.
For the New Dehli India example, after working through the relationships, it is found that its Köppen-‐Geiger Climate Classification is BSh, or Arid Steppe hot.
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Name: ______________________________________________
Determine your local Köppen-Geiger Climate Classification - Worksheet
1. Identify a city or town to study where long-‐term precipitation and temperature data are acquired:
Location Name:__________________________________________________________
Latitude (°N or °S): ______________ Longitude (°E or °W): ______________
2. Attempt to describe the climate of your chosen location. Things to take into consideration are: how much precipitation your location receives, when the most precipitation falls, if your summers are hot or cold, etc.
3. Fill in the following tables (Table A and Table B) with values for your location:
Value Tann Annual Temperature (°C) Tmin Temperature of Coldest Month
(°C)
Tmax
Temperature of Warmest Month (°C)
Pann Accumulated Annual
Precipitation (mm)
A Pth Precipitation Threshold (mm)
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The following relationships will be needed to calculate the precipitation threshold:
• If most of the precipitation falls in the summer, the precipitation threshold is calculated by multiplying the annual temperature by 2 and adding 28
• If most of the precipitation falls in the winter, the precipitation threshold is calculated by multiplying the annual temperature by 2
• If precipitation is spread throughout the year, the precipitation threshold is calculated by multiplying the annual temperature by 2 and adding 14
Value Pwmax Amount of precipitation in wettest winter month (mm) Pwmin Amount of precipitation in driest winter month (mm) Psmax Amount of precipitation in wettest summer month (mm) Psmin Amount of precipitation in driest summer month (mm)
B Are there at least 4 months with T greater than 10°C (yes, no)
4. Work through the Köppen-‐Geiger Climate Classification Key to determine your
chosen location’s Köppen-‐Geiger Climate Classification.
5. Write your main climate classification: ____________________________________________________
6. Write your first sub-‐climate classification: ________________________________________________
7. Write your second sub-‐climate classification (if applicable):___________________________________________________________________________________
8. Combine your answers from numbers 5-‐8 to determine your Köppen-‐Geiger Climate Classification. Write it here: _________________________________________________________________________________
9. How does your description in number 2 correspond to your determined climate classification?
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Köppen-Geiger Climate Classification Key
Main Climate Classification
POLAR (E) 1. Is the site a polar climate (E)? Condition for polar climate: Tmax < 10°C If YES, go to POLAR If NO, go to ARID (pg. 4) (below)
ARID (B) 1. Is the site an arid climate (B)? Condition for arid climate: Pann < 10 x Pth If YES, go to ARID If NO, go to EQUATORIAL (pg. 4) (below)
EQUATORIAL (A) 1. Is the site an equatorial climate (A)? Condition for equatorial climate: Tmin ≥ 18°C
If YES, go to EQUATORIAL If NO, go to WARM TEMPERATE (pg. 5) (below)
WARM TEMPERATE (C) 1. Is the site a warm temperate climate (C)? Condition for warm temperate climate: ¯ˉ3°C < Tmin < 18°C
If YES, go to WARM TEMPERATE If NO, go to SNOW (pg. 5) (below)
SNOW (D) 1. Is the site a snow climate (D)? Condition for snow climate: Tmin ≤ ¯ˉ3°C If YES, go to SNOW
(pg. 7)
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Sub-climate Classification(s)
POLAR (E) 1. Is the site tundra (T)? Condition for tundra climate: 0°C < Tmax < 10°C If YES , If NO, go to 2 DONE! (below) 2. Is the site frost (F)? Condition for frost climate: Tmax < 0°C DONE!
ARID (B) 1. Is the site a steppe climate (S)? Condition for steppe climate: Pann > 5 x Pth If YES, go to 3 If NO, go to 2 (below) (below) 2. Is the site a desert climate (D)? Condition for steppe climate: Pann ≤ 5 x Pth If YES, go to 3 (below) 3. Is the site a cold climate (k)? Condition for cold climate: Tann ≤ 18°C If YES, If NO, go to 4 DONE! (below) 4. Is the site a hot climate (h)? Condition for cold climate: Tann > 18°C DONE!
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EQUATORIAL (A) 1. Is the site a rainforest, fully humid climate (f)? Condition for rainforest, fully humid climate: Pmin ≥ 60mm If YES, If NO, go to 2 DONE! (below) 2. Is the site a monsoon climate (m)? Condition for monsoon climate: Pann ≤ 5 x Pth If YES, If NO, go to 3 DONE! (below) 3. Is the site a savannah, dry summer climate (s)? Condition for savannah, dry: summer climate: Psmin ≤ 60mm If YES, If NO, go to 4 DONE! (below) 4. Is the site a savannah, dry winter climate (w)? Condition for savannah, dry: winter climate: Pwmin ≤ 60mm DONE!
WARM TEMPERATE (C) 1. Is the site a dry summer climate (s)? Conditions for dry summer Psmin < Pwmin climate: Pwmax > 3 x Psmin Psmin < 40 mm If YES, go to4 If NO, go to 2 (pg. 6) (pg. 6)
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WARM TEMPERATE (C) cont’d 2. Is the site a dry winter climate (w)? Conditions for dry winter Pwmin < Psmin climate: Psmax > 10 x Pwmin If YES, go to 4 If NO, go to 3 (below) (below) 3. Is the site a fully-humid climate (f)? Conditions for fully-‐humid climate: Neither dry summer or dry winter If YES, go to 4 (below) 4. Is the site a hot summer climate (a)? Conditions for hot summer climate: Tmax ≥ 22°C If YES, If NO, go to 5 DONE! (below) 5. Is the site a warm summer climate (b)? Conditions for warm summer at least 4 months with climate: T ≥ 10°C If YES, If NO, go to 6 DONE! (below) 6. Is the site a cool summer climate (c)? Conditions for cool summer Tmin > ¯ˉ38°C climate: If YES, If NO, go to 7 DONE! (pg. 7)
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WARM TEMPERATE (C) cont’d 7. Is the site an extremely continental climate (a)? Conditions for extremely Tmin ≤ ¯ˉ38°C continental climate: If YES, DONE!
SNOW (D) 1. Is the site a dry summer climate (s)? Conditions for dry summer Psmin < Pwmin climate: Pwmax > 3 x Psmin Psmin < 40 mm If YES, go to 4 If NO, go to 2 (below) (below) 2. Is the site a dry winter climate (w)? Conditions for dry winter Pwmin < Psmin climate: Psmax > 10 x Pwmin If YES, go to 4 If NO, go to 3 (below) (below) 3. Is the site a fully-humid climate (f)? Conditions for fully-‐humid Neither dry summer or climate: dry winter If YES, go to 4 (below) 4. Is the site a hot summer climate (a)? Conditions for hot summer Tmax ≥ 22°C climate: If YES, If NO, go to 5 DONE! (pg. 8)
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SNOW (D) cont’d 5. Is the site a warm summer climate (b)? Conditions for warm summer at least 4 months with climate: T ≥ 10°C If YES, If NO, go to 6 DONE! (below) 6. Is the site a cool summer climate (c)? Conditions for cool summer Tmin > ¯ˉ38°C climate: If YES, If NO, go to 7 DONE! (below) 8. Is the site an extremely continental climate (a)? Conditions for extremely Tmin≤ ¯ˉ38°C continental climate: If YES, DONE!