FLOW CHART FOR KPPENS CLIMATE CLASSIFICATIONFIRST LETTER SYMBOLA TROPICAL CLIMATES

Monthly temperatures all greater than or equal to 18C.B DRY CLIMATES

Potential evapotranspiration exceeds precipitation.C WET TEMPERATE (MARITIME) CLIMATES

Average temperature of coldest month is at least -3Cbut less than 18C; warmest month at least 10C.

D COOL TEMPERATE (CONTINENTAL) CLIMATESColdest month less than -3C; warmest month at least10C.

E POLAR CLIMATESMonthly temperatures all less than 10C.

SECOND LETTER SYMBOLF FROST/ICE

All months less than 0C.S STEPPE

See Figure 1.T TUNDRA

Warmest month at least 0C.W DESERT

See Figure 1.f WET ALL YEAR

See Figure 2; or, every month receives at least 30 mm ofprecipitation for C and D climates.

m MONSOONShort dry season.

s SUMMER DRYSee Figure 2; or, driest summer month less than or equalto 1/3 of precipitation of wettest winter month.

w WINTER DRYSee Figure 2; or, driest winter month less than or equalto 1/10 of precipitation of wettest summer month.

THIRD LETTER SYMBOLa HOT SUMMER

Warmest month greater than or equal to 22C.b WARM LONG SUMMER

At least 4 months have temperatures of 10C or above butunder 22C.

c SHORT SUMMER1 to 3 months have temperatures of 10C or above butunder 22C.

d SEVERE WINTERColdest month less than -38C.

h HOTAnnual temperature is 18C or greater.

k COOLAnnual temperature is less than 18C.

Ds-None exist

EF

ET

Af

Dfd

Dwd

BWk

BWh

BSk

BSh

Am

Aw

As

Cfa

Cwa

Csa

Dfa

Dwa

Cfb

Cwb

Cfc

Cwc-None exist

Csb

Csc-None exist

Dfb

Dfc

Dwb

Dwc

FLOW CHART FOR KPPENS CLIMATE CLASSIFICATIONT and P refer to normal monthly values of Temperature and Precipitation

Is every T

FLOW CHART FOR KPPENS CLIMATE CLASSIFICATION

30C

20C

10C

0C

-10C

0 mm

200 mm

400 mm

600 mm

800 mm

Normal Annual Temperature

Normal Annual Precipitation

Even Distribution

25C

15C

5C

-5C

-15C

100 mm

300 mm

500 mm

700 mm

900 mm

B W B S

A, C, D, or E

Normal Annual Temperature

30C

20C

10C

0C

-10C

0 mm

200 mm

400 mm

600 mm

800 mm

Normal Annual Precipitation

Winter Concentration

25C

15C

5C

-5C

-15C

100 mm

300 mm

500 mm

700 mm

900 mm

B W B S

A, C, D, or E

30C

20C

10C

0C

-10C

0 mm

200 mm

400 mm

600 mm

800 mm

Normal Annual Temperature

Normal Annual Precipitation

Summer Concentration

25C

15C

5C

-5C

-15C

100 mm

300 mm

500 mm

700 mm

900 mm

B W B S

A, C, D, or E

FIGURE 1

Figure 1: First, divide the year into two six-month seasons: April-September and October-March, representing Summer or Winter in their respective hemispheres.If 70% or more of the annual precipitation total falls into one of these two seasons, then that season is considered to have a precipitation concentration.If not, then precipitation is considered to fall evenly throughout the year.

FIGURE 2

2,500 mm

1,500 mm

500 mm

0 mm

20 mm

40 mm

60 mm

80 mm

Mean Annual Precipitation

Precipitation of Driest Month

3,000 mm

2,000 mm

1,000 mm

0 mm

10 mm

30 mm

50 mm

70 mm

Af

A m

Aw, As

Figure 2: First, divide the year into two six-month seasons: April-September and October-March, representing Summer or Winter in their respective hemispheres.If 70% or more of the annual precipitation total falls into one of these two seasons, then that season is considered to have a precipitation concentration.If not, then precipitation is considered to fall evenly throughout the year.