Geoscience Reference
In-Depth Information
Characteristics of the Major Global BiomesT
T A B L E 1 0 . 1
Average Annual
Precipitation and
Moisture Patterns
Average Annual
Temperature Patterns
Biome
Dominant Vegetation
Köppen Climate
Tropical Rainforest
Broadleaf evergreen trees.
Dense canopy with open
forest floor. Lianas (vines)
and epiphytes.
Af, Am
(wet side)
180 cm-400 cm
(71 in.-158 in.)
20°C-30°C
(68°F-86°F ).
Tropical Deciduous
Forest and Scrub
Ecotone between rain-
forest and grasslands;
broadleaf trees with sea-
sonal leaf fall.
Am, Aw
Seasonal, but always
warmer than 18°C
(64°F).
130 cm-200 cm
(51 in.-79 in.), with distinct
winter dry season.
Midlatitude
Deciduous Forest
Broadleaf trees with
seasonal leaf fall.
Cfa, Cwa, Dfa, Dwa, Dwb
Hot summers and cool
to cold winters.
75 cm-150 cm (30 in.-60 in.),
with summer maximum; no
seasonal water deficits.
Mediterranean
Woodland and
Shrub
Individual short shrubs
separated by grassy
patches.
Csa, Csb
Warm summers and
cool winters.
25 cm-65 cm (10 in.- 26 in.);
winter surplus and summer
deficit.
Midlatitude
Coniferous Forest
Needle-leaf evergreen
trees, including spruce,
pine, fir.
Cfa, Cfb, Cfc, Cwa, Dfb,
Hot summers with cool
winters in southeast;
cold winters and cool
summers in northern
conifers and highlands.
Cool winters and warm
summers in west-coast
rainforest.
75 cm-150 cm (30 in.-60 in.)
in southeastern pines;
30 cm-100 cm (12 in.-39 in.)
in northern conifers and
highlands; 150 cm-500
cm (60 in.-197 in.) in west
coast rainforests.
Boreal Forest
Needle-leaf conifers,
including spruce, pine, fir.
Dfc, Dwc, Dfd
Long, cold winters and
short, cool summers.
30 cm-100 cm (12 in.-39 in.);
no seasonal water deficit;
ground frozen most of year.
Tropical Savanna
Ecotone between tropical
forests and deserts; grass-
lands with isolated trees.
Aw
Seasonal, but always
warmer than 18°C
(64°F).
9 cm-150 cm (4 in.- 60 in.);
short summer wet season
and long dry season.
Midlatitude
Grassland
Tall-grass prairie in humid
areas to short-grass steppes
in more arid regions.
BSk, Dfa, Dfb, Dwa, Dwb
Seasonal, with hot
summers and cool to
cold winters.
25 cm-75 cm (10 in.- 30 in.);
summer water stress.
Hot and Dry
Desert
Xerophytes such as
succulents and cacti
trending to large patches
of bare ground.
BWh, BWk
Less than 2 cm (0.7 in.);
perpetual moisture deficits.
Perpetually hot.
Semi-Arid and
Cold Desert
Short-grass and dry shrubs;
patches of bare ground.
BSh, BSk
Average annual tem-
perature = 18°C (64°F).
2 cm-25 cm (0.7 in.- 10 in.).
Tundra
Stunted shrubs and
sedges; mosses, lichens.
ET, Dwd
Above freezing only
2 or 3 months of year,
with warmest month
<10°C (50°F).
15 cm-180 cm (6 in.- 71 in.);
no seasonal moisture defi-
cit; frozen ground virtually
all year.
Alpine and
Arctic Ice
Some algae perhaps.
EF, H
Less than 10 cm (4 in.).
Frigid.
