Koppen-Geiger Climate Classification Key

Major Climate

Types

1. Is the temperature of the warmest month [Tmax] less than 10° C?

Go to POLAR 2. Is the accumulated annual precipitation [Pann] less than 10 x Pth?

Go to ARID 3. Is the temperature of the coldest month [Tmin] more than or equal to 18° C?

Go to EQUATORIAL

4. Is the temperature of the coldest month [Tmin] less than 18 °C but more than -3° C?

Go to WARM

TEMPERATE

5. Is the temperature of the coldest month [Tmin] less than or equal to -

3° C?

Go to SNOW

YES NO

YES NO

YES NO

YES NO

YES

1. Is [Tmax] less than 0° C?

FROST (F)2. Is [Tmax] more than 0° C but less

than 10° C?

TUNDRA (T)

Sub-climate ClassificationPOLAR (E)

Possible Polar Climate Classifications

• Polar Frost (EF)• Polar Tundra (ET)

YES NO

YES

Possible Arid Climate Classifications

• Arid Steppe Cold (BSk)• Arid Steppe Hot (BSh)• Arid Desert Cold (BWk)• Arid Dessert Hot (BWh)

1. Is [Pann] more than 5 x Pth?

STEPPE (S) Then go to 3

2. Is [Tmax] more than 0° C but less

than 10° C?

DESERT (W) Then go to 3

Sub-climate ClassificationARID (B)

YES

3. Is [Tann] less than or equal to 18°

C?

COLD (k) HOT (h)

YES NO

YES NO

1. Is [Pmin] more than or equal to

60 mm?

RAINFOREST FULLY HUMID (f)

2. Is [Pann] less than or equal to

5 x Pth?

MONSOONAL (m)

3. Is [Psmin] less than or equal to

60 mm?

SAVANNAH SUMMER DRY (s)

4. Is [Pwmin] less than or equal to

60 mm?

SAVANNAH WINTER DRY (w)

Sub-climate ClassificationEQUATORIAL (A)

Possible Equatorial Climate Classifications

• Equatorial Rainforest Fully Humid (Af)• Equatorial Monsoon (Am)• Equatorial Savannah Summer Dry (As)• Equatorial Savannah Winter Dry (Aw)

YES NO

YES NO

YES NO

YES

Possible Warm Temperate Climate Classifications

• Warm temperate dry hot summer (Csa)• Warm temperate dry warm summer (Csb)• Warm temperate dry cool summer (Csc)• Warm temperate dry winter, hot summer (Cwa)• Warm temperate dry winter, warm summer (Cwb)• Warm temperate dry winter, cool summer (Cwc)• Warm temperate fully humid hot Summer (Cfa)• Warm temperate fully humid warm summer (Cfb)• Warm temperate fully humid cool summer (Cfc)

Sub-climate ClassificationWARM TEMPERATE (C)

3. Is [Tmax] more than or equal to

22° C?

HOT SUMMER (a)

4. Do at least 4 months have T greater than or equal to 10° C?

WARM SUMMER (b)

5. Is [Tmin] more than -38° C?

COOL SUMMER (c)

EXTREMELY CONTINENTAL (a)

YES NO

YES NO

YES NO

1. Is: [Psmin] less than [Pwmin] And [Pwmax] more than 3 x [Psmin] And [Psmin] less than

40 mm?

SUMMER DRY (s) Then go to 3

2. Is: [Pwmin] less than [Psmin] And [Psmax]

more than 10 x [Pwmin]

WINTER DRY (w) Then go to 3

FULLY HUMID (f)Then go to 3

YES NO

YES NO

Possible Snow Climate Classifications• Snow fully humid, hot summer (Dfa)• Snow fully humid, warm summer (Dfb)• Snow fully humid, cold summer (Dfc)• Snow fully humid, extremely continental (Dfd)• Snow dry, hot summer (Dsa)• Snow dry, warm summer (Dsb)• Snow dry, cool summer (Dsc)• Snow dry summer, extremely continental (Dsd)• Snow dry winter, hot summer (Dwa)• Snow dry winter, warm summer (Dwb)• Snow dry winter, cool summer (Dwc)• Snow dry winter extremely continental (Dwd)

3. Is [Tmax] more than or equal to

22° C?

HOT SUMMER (a)

4. Do at least 4 months have T greater than or equal to 10° C?

WARM SUMMER (b)

5. Is [Tmin] more than -38° C?

COOL SUMMER (c) EXTREMELY CONTINENTAL (a)

Sub-climate ClassificationSNOW (D)

1. Is: [Psmin] less than [Pwmin] And [Pwmax] more than 3 x [Psmin] And [Psmin] less than

40 mm?

SUMMER DRY (s)Then go to 3

2. Is: [Pwmin] less than [Psmin] And [Psmax]

more than 10 x [Pwmin]

WINTER DRY (w)Then go to 3

FULLY HUMID (f)Then go to 3

YES NO

YES NO

YES NO

YES NO

YES NO

What is Your Climate Classification?Data SheetLocation: _Tokyo, Japan_______________Lat/Long: _35°41 22.22__N _139°41 30.12″_ E ′ ′

Table B: CalculationsAbbreviation Description Value

Tann Annual Air Temperature (C)[Add all 12 Mean Air Temperatures and divide by 12]

14.4

Tmin Air Temperature of the Coldest Month (C)[The lowest value in the Mean Air Temp column]

3.6

Tmax Air Temperature of the Warmest Month (C)[The highest value in the Mean Air Temp column]

26.1

Pann Accumulated Annual Precipitation (mm)[Add all 12 Monthly Accumulated Precipitation Values]

1418.6

Pth Precipitation Threshold (mm) [If 70% or more precip. falls in summer then Pth = (Tann x2 +28 If 70% or more falls in winter then Pth = Tann x 2 If netiher of the above, then Pth = (Tann x 2 + 14]

42.9

Pmin Amount of Precipitation in the driest month (mm)[The lowest value for Monthly Accumulated Precipitation]

48.5

Psmax Amount of Precipitation in the wettest summer month (mm)[Identify summer, the highest Monthly Accumulated Precipitation in these months]

213.4

Psmin Amount of Precipitation in the driest summer month (mm)[Identify summer, the lowest Monthly Accumulated Precipitation in these months]

48.5

Pwmax Amount of Precipitation in the wettest winter month (mm)[Identify winter, the highest Monthly Accumulated Precipitation in these months]

194.1

Pwmin Amount of Precipitation in the driest winter month (mm)[Identify winter, the lowest Monthly Accumulated Precipitation in these months]

49.9

Table A: 30 Year Data

Month Mean Air Temp (C)

Monthly Accumulated Precipitation (mm)

January 3.6 49.9

February 4.3 71.5

March 7.4 106.4

April 13.0 129.2

May 17.3 144

June 20.8 176

July 24.7 135.6

August 26.1 48.5

September 22.4 213.4

October 16.5 194.1

November 11.1 95.6

December 6.1 54.4

Additional Pth information needed:Does 70% or more of the precipitation fall in the summer? In the winter? Or neither?April-Sept. are summer northern hemisphere/winter southernOctober-March are winter northern hemisphere/summer southern

Example #1

Koppen-Geiger Climate Classification Key

Major Climate

Types

1. Is the temperature of the warmest month [Tmax] less than 10° C?

Go to POLAR 2. Is the accumulated annual precipitation [Pann] less than 10 x Pth?

Go to ARID 3. Is the temperature of the coldest month [Tmin] more than or equal to 18° C?

Go to EQUATORIAL

4. Is the temperature of the coldest month [Tmin] less than 18 °C but more than -3° C?

Go to WARM

TEMPERATE

5. Is the temperature of the coldest month [Tmin] less than or equal to -

3° C?

Go to SNOW

YES NO

YES NO

YES NO

YES NO

YES

Example #1 - Tokyo

Tmax = 26.1 C

Pann = 1,418.6 mmPth x 10 = 429

Tmin = 3.6 C

Possible Warm Temperate Climate Classifications

• Warm temperate dry hot summer (Csa)• Warm temperate dry warm summer (Csb)• Warm temperate dry cool summer (Csc)• Warm temperate dry winter, hot summer (Cwa)• Warm temperate dry winter, warm summer (Cwb)• Warm temperate dry winter, cool summer (Cwc)• Warm temperate fully humid hot Summer (Cfa)• Warm temperate fully humid warm summer (Cfb)• Warm temperate fully humid cool summer (Cfc)

3. Is [Tmax] more than or equal to

22° C?

HOT SUMMER (a)

4. Do at least 4 months have T greater than or equal to 10° C?

WARM SUMMER (b)

5. Is [Tmin] more than -38° C?

COOL SUMMER (c)

EXTREMELY CONTINENTAL (a)

1. Is: [Psmin] less than [Pwmin] And [Pwmax] more than 3 x [Psmin] And [Psmin] less than

40 mm?

SUMMER DRY (s) Then go to 3

2. Is: [Pwmin] less than [Psmin] And [Psmax]

more than 10 x [Pwmin]

WINTER DRY (w) Then go to 3

FULLY HUMID (f)Then go to 3

YES NO

YES NO

Sub-climate ClassificationWARM TEMPERATE (C)

YES NO

YES NO

YES NO

1. Psmin 48.5 is less than Pwmin 49.9Pwmax 194.1 is more than Psmin x 3 145.5 but Psmin 48.5 is not > 40 mm

2. Pwmin 49.9 is not less than Psmin 48.5

3. Tmax = 26.1

What is Your Climate Classification?Data SheetLocation: _Anchorage, Alaska___Lat/Long: 61°13 05″N 149°53 33″W′ ′

Table B: CalculationsAbbreviation Description Value

Tann Annual Air Temperature (C)[Add all 12 Mean Air Temperatures and divide by 12]

1.9

Tmin Air Temperature of the Coldest Month (C)[The lowest value in the Mean Air Temp column]

-10.3

Tmax Air Temperature of the Warmest Month (C)[The highest value in the Mean Air Temp column]

14.2

Pann Accumulated Annual Precipitation (mm)[Add all 12 Monthly Accumulated Precipitation Values]

383.8

Pth Precipitation Threshold (mm) [If 70% or more precip. falls in summer then Pth = (Tann x2 +28 If 70% or more falls in winter then Pth = Tann x 2 If netiher of the above, then Pth = (Tann x 2 + 14]

17.8

Pmin Amount of Precipitation in the driest month (mm)[The lowest value for Monthly Accumulated Precipitation]

13.1

Psmax Amount of Precipitation in the wettest summer month (mm)[Identify summer, the highest Monthly Accumulated Precipitation in these months]

66.7

Psmin Amount of Precipitation in the driest summer month (mm)[Identify summer, the lowest Monthly Accumulated Precipitation in these months]

13.1

Pwmax Amount of Precipitation in the wettest winter month (mm)[Identify winter, the highest Monthly Accumulated Precipitation in these months]

48.6

Pwmin Amount of Precipitation in the driest winter month (mm)[Identify winter, the lowest Monthly Accumulated Precipitation in these months]

15.2

Table A: 30 Year Data

Month Mean Air Temp (C)

Monthly Accumulated Precipitation (mm)

January -10.3 20.9

February -7.5 18.8

March -4.2 15.2

April 1.8 13.1

May 7.7 14.8

June 12.2 24.5

July 14.2 45.6

August 13.2 64.8

September 8.8 66.7

October 1.8 48.6

November -5.5 25.8

December -9.7 25

Additional Pth information needed:Does 70% or more of the precipitation fall in the summer? In the winter? Or neither?April-Sept. are summer northern hemisphere/winter southernOctober-March are winter northern hemisphere/summer southern

Example #2

Koppen-Geiger Climate Classification Key

Major Climate

Types

1. Is the temperature of the warmest month [Tmax] less than 10° C?

Go to POLAR 2. Is the accumulated annual precipitation [Pann] less than 10 x Pth?

Go to ARID 3. Is the temperature of the coldest month [Tmin] more than or equal to 18° C?

Go to EQUATORIAL

4. Is the temperature of the coldest month [Tmin] less than 18 °C but more than -3° C?

Go to WARM

TEMPERATE

5. Is the temperature of the coldest month [Tmin] less than or equal to -

3° C?

Go to SNOW

YES NO

YES NO

YES NO

YES NO

YES

What is Your Climate Classification?Data SheetLocation: ________________Lat/Long: __________N or S __________ E or W

Table B: CalculationsAbbreviation Description Value

Tann Annual Air Temperature (C)[Add all 12 Mean Air Temperatures and divide by 12]

Tmin Air Temperature of the Coldest Month (C)[The lowest value in the Mean Air Temp column]

Tmax Air Temperature of the Warmest Month (C)[The highest value in the Mean Air Temp column]

Pann Accumulated Annual Precipitation (mm)[Add all 12 Monthly Accumulated Precipitation Values]

Pth Precipitation Threshold (mm) [If 70% or more precip. falls in summer then Pth = (Tann x2 +28 If 70% or more falls in winter then Pth = Tann x 2 If netiher of the above, then Pth = (Tann x 2 + 14]

Pmin Amount of Precipitation in the driest month (mm)[The lowest value for Monthly Accumulated Precipitation]

Psmax Amount of Precipitation in the wettest summer month (mm)[Identify summer, the highest Monthly Accumulated Precipitation in these months]

Psmin Amount of Precipitation in the driest summer month (mm)[Identify summer, the lowest Monthly Accumulated Precipitation in these months]

Pwmax Amount of Precipitation in the wettest winter month (mm)[Identify winter, the highest Monthly Accumulated Precipitation in these months]

Pwmin Amount of Precipitation in the driest winter month (mm)[Identify winter, the lowest Monthly Accumulated Precipitation in these months]

Table A: 30 Year Data

Month Mean Air Temp (C)

Monthly Accumulated Precipitation (mm)

January

February

March

April

May

June

July

August

September

October

November

December

Additional Pth information needed:Does 70% or more of the precipitation fall in the summer? In the winter? Or neither?April-Sept. are summer northern hemisphere/winter southernOctober-March are winter northern hemisphere/summer southern